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Colour Television
Chassis
FTV1.9DE
AA
CL 965320690-163.eps 020999
Contents
1 2 3. 4 5 6 7 8 9 10 11 12 Introduction Mechanical instructions Blockdiagram Service modes Preconditioner VsVa supply Audio Video control PDP- Limesco Audio amplifier LED panel Switch panel YUV / YC input
Page
2 5 11 12 26 38 54 68 80 81 82 83
©
Copyright reserved 1999 Philips Consumer Electronics B.V. Eindhoven, The Netherlands. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise without the prior permission of Philips. Printed in The Netherlands Subject to modification 5 3122 785 10036
Published by JvR 9969 Service PaCE
2
1. Introduction
FTV1.9DE Display Box
1.
Introduction
CONFIGURATIONS
TV-CONFIGURATION
R, G, B, HS, VS RECEIVER BOX CONFIG_IDENT DIS_RC_5 µP UART µP DISPLAY BOX
MONITOR-CONFIGURATION
R, G, B, H, V PERSONAL COMPUTER CONFIG_IDENT µP DDC µP DISPLAY BOX
CL 96532069_002.eps 240899
The successor of the FTV1.5 is the FTV1.9, which had to be cheaper,and had to make as much as possible "re-use" of PWB's from the FTV1.5. It is built around an E-Box (= Receiver Box) and a 42" Monitor (= Display Box). Within the Monitor a Fujitsu Plasma Display panel - version 5 - is used. For the FTV1.9, the Monitor can be used in two applications. · Stand-alone configuration, monitor is connected to a PC or a laptop · TV configuration, where the monitor is connected to the Ebox. The Monitor is a separate device, which can also be sold and serviced separately. The monitor, as a stand-alone unit, can be serviced by using a test pattern coming from the PDP-LIMESCO panel on the monitor itself or via a PC/laptop by using ComPair via the ComPair connector. FTV1.9 Family has been set up for Europe, USA, Asian and LATAM markets. The Europe type consisting of 1 version, having no diversity.
Personal notes
FTV1.9DE Display Box
1. Introduction 1.1 Description of used panels
3
1.1
Description of used panels
VS/VA Supply PDP Discharge Audio Amplifier PDP Limesco Pre-conditioner AV Control YUV/YC Input
CL 96532069_131.EPS 120899
The panels are: 1. VsVa supply. At this panel all the supply voltages will be generated for the display itself, the electronics of the display and our PCB's. This panel contains also the fan control and the protection circuits. 2. PDP Discharge Panel. Temporarily used in the DEMmodels of the FTV1.9. In the final models this panel is either going to be integrated into the VsVa panel or is going to be re-designed as a separate new panel. The function of this panel is to discharge the big capacitor of the Vs-supply and the Va-supply (minor reason). If these capacitors are not discharged it can take up to 60 seconds before the set restarts after turning it OFF and ON again. 3. Audio amplifier. This panel is almost the same as the GFL audio amplifier. Some small changes have been made like other plugs, deleting a switch and external speaker connectors and an adaptation of the outlines, just to mount the panel at the backside of the Monitor. 4. Preconditioner. At this panel the mains input and mains output (to connect the E-Box) is located. After the mains input, the mains filter is placed. The panel contains also the preconditioner. This is an auto voltage function from 95V ... 264VAC in to 380VDC out and the standby supply for the µP and the NVM. 5. AV Control. At this panel the VGA, audio and control (UART or DDC) signals enter the Monitor. These signals will be buffered and are available at the output of this panel for feedthrough (except the control signals). The same signals will be fed to the Audio part (including an (optional) audio
Personal notes
4
1. Introduction 1.1 Description of used panels
delay to correct the timing between video and audio) and to the video control IC to control the RGB signals. Also the µP for the panel control in the Monitor is located on this board. The audio filters for the high and low/medium signals are also located on the AV Control board. PDP LIMESCO. This panel converts the analogue video after gamma correction to a digital video signal, which is connected to the PDP itself. The OSD generator is located at the PDP LIMESCO, close to the LIMESCO IC for the insertion of digital OSD information. The LIMESCO IC is responsible for the scaling of the signals of the various standard TV standards, VGA formats at this board. The H and V position is corrected by an EPLD. YUV YC input panel. This board gives the possibility to attach several video formats to the stand-alone display. It also has one stereo audio connection. · Video input signals: YUV on three CINCHES (Y, Cb, Cr). YC on Hosiden connector (SVHS). CVBS on CINCH. CVBS on BNC. · Audio input signals: L and R on 2 CINCHES. · Output signal (AV Control): RBG-signal. H-sync and Vsync signal. L and R audio signal. LED Display panel. At this panel, the LED's and the IRReceiver is located. Switch Display panel. At this panel, the low power mains switch is located. With this switch a relay is controlled to switch ON and OFF the monitor
FTV1.9DE Display Box
Personal notes
6.
7.
8. 9.
FTV1.9DE Display Box
2. Mechanical instructions 2.1 Introduction:
VS/VA SUPPLY panel.
5
There are pre-defined service positions for the following panels: 1. VS/VA SUPPLY panel. 2. PDP DISCHARGE panel. 3. AUDIO AMPLIFIER panel. 4. PRE-CONDITIONER panel. 5. AV CONTROL panel. 6. PDP LIMESCO panel. 7. YUV/YC INPUT panel. 8. LED DISPLAY panel. 9. SWITCH DISPLAY panel. Before these panels can be accessed, the rear cover has to be removed:
2. Mechanical instructions2.1 Introduction:
VS/VA Supply
FD07
1
4 2
2
3
CL 96532069_132.EPS 120899
1
Figure 2-3
CL 96532069_130.EPS 120899
Figure 2-1
1. Place the Display Box in the service stand via 2 reinforced cushions (order code: 3122 126 30181). 2. Remove the 9 fixation screws of the rear cover. 3. Remove the rear cover (during removal push it slightly upwards).
1. Disconnect Fan Supply cable from connector FD07 in the upper left corner [1]. 2. Remove the 7 fixation screws of the panel [2]. 3. Place panel on the 2 hinges, which are located near the right corners of the panel [3]. 4. Use the mechanical service part (extension cable assembly, 12NC: 3122 785 90006) to extend the Fan Supply cable [4]. 5. The copper side is now accessible from the left. PDP DISCHARGE panel. As in the FTV 1.5, this panel must be exchanged completely if defective.
VS/VA Supply PDP Discharge Audio Amplifier PDP Limesco Pre-conditioner AV Control YUV/YC Input
CL 96532069_131.EPS 120899
Figure 2-2
1. All panels are now accessible.
6
2. Mechanical instructions 2.1 Introduction:
PRECONDITIONER panel.
FTV1.9DE Display Box
AUDIO AMPLIFIER panel.
Audio Amplifier
Pre-conditioner
1
4 3 1 1 22 5 5
2 3 2
Figure 2-4
CL 96532069_134.EPS 120899
4
CL 96532069_135.EPS 120899
Figure 2-5
1. Some testpoints are accessible at the B-side [1]. 2. If this is not sufficient, remove the 3 fixation screws of the panel [2]. 3. Panel now can be hinged on the left side to access the Aside (soldering side) [3].
1. Disconnect the 2 grounding wires from the shielding plate by pressing the small lever on the connector while pulling [1]. 2. Remove the 2 ferrite ring cores from their fixations [2]. 3. Remove the 5 fixation screws of the panel [3]. 4. Place panel on the 2 hinges, which are located, near the left corners of the panel [4]. 5. Reconnect grounding wires to the extra connectors on the shielding plate at the left side [5]. 6. The copperside becomes accessible now from the right side. AUDIO VIDEO CONTROL panel.
AV Control
CL 96532069_136.EPS 120899
Figure 2-6
FTV1.9DE Display Box
2. Mechanical instructions 2.1 Introduction:
YUV/YC INPUT panel.
7
This panel has no service position for accessing the A-side, however all service test points are accessible at the B-side (see Service Manual). In case some components must be (de)soldered, all fixation screws (6 for the panel, 5 at the metal connector plate) and all cables must be removed to access the A-side. PDP LIMESCO panel.
YUV/YC Input
PDP Limesco
SVHS BNC
3
2 2 1 1 1 1 2 1
CL 96532069_137.EPS 120899 CL 96532069_138.EPS 120899
Figure 2-8
Figure 2-7
This panel has no pre-defined service position. For access of the A-side, the panel has to be removed: 1. Remove the 4 screws at the metal connector plate [1]. 2. Remove the 2 fixation screws of the panel [2]. 3. Panel can be removed now to access the A-side [3]. LED DISPLAY panel.
All SMC's are located on the B-side, so all testpoints are accessible. In case some components must be (de)soldered, the hinge construction can be used to access the A-side. 1. Remove the 4 fixation screws of the panel [1]. 2. Panel can now be hinged to access soldering side [2].
2 2
CL 96532069_139.EPS 120899
1
Figure 2-9
8
2. Mechanical instructions 2.1 Introduction:
FTV1.9DE Display Box
1. Remove 2 x 2 screws at the sides and 4 screws at the bottom of the front cover [1]. 2. Remove the front cover (it hinges at the top). During removal unplug the cable of the LED DISPLAY panel at the SWITCH DISPLAY panel (connector SD11) [2].
Personal notes
3
CL 96532069_140.EPS 120899
Figure 2-10
1. The LED DISPLAY panel can be removed now by unscrewing 1 fixation screw [3]. SWITCH DISPLAY panel. 1. Remove front cover (for a description see Chapter 2.1.8 'LED DISPLAY panel').
3
CL 96532069_141.EPS 120899
Figure 2-11
1. The SWITCH DISPLAY panel can be removed now by unscrewing 3 fixation screws [3].
FTV1.9DE Display Box
2. Mechanical instructions 2.2 Exchanging parts
9
Some parts of the FTV1.9 Display Box must be exchanged if defective: 1. GLASS PLATE. 2. LOUDSPEAKER. 3. PLASMA DISPLAY PANEL [PDP].
2.2 Exchanging parts
3
Exchanging of the GLASS PLATE.
4
1. First unplug (remove Mains and VGA cable) the Display Box . 2. Remove front cover (for a description see Chapter 2.1.8 'LED DISPLAY panel').
3
4
3 3
CL 96532069_143.EPS 120899
2
Figure 2-13
1. The LOUDSPEAKER can now be removed by disconnecting its cable and removing the 4 fixation screws at the top and bottom of the speakerbox. Be sure to remove the correct screws, otherwise the speaker system will be damaged (it is an airtight system). Exchanging of the PDP.
5 3 4
CL 96532069_142.EPS 120899
Figure 2-12
1. Now the GLASS PLATE can be removed by unscrewing all screws [3] and removing all glass clips [4]. Exchanging of a LOUDSPEAKER. 1. First unplug (remove Mains and VGA cable) the Display Box. 2. Remove front cover (for a description see Chapter 2.1.8 'LED DISPLAY panel').
1. First unplug (remove Mains and VGA cable) the Display Box. 2. Place the rear side of the Display Box on a foam cushion (be sure the metal rear cover is mounted in order to prevent damaging of the electronic panels). 3. Remove front cover (for a description see Chapter 2.1.8 LED DISPLAY panel). 4. Now the GLASS PLATE can be removed by unscrewing all screws and removing all glass clips (for a description see Chapter 2.2.1. 'Exchanging of the GLASS PLATE').
6
CL 96532069_144.EPS 120899
Figure 2-14
10
2. Mechanical instructions 2.2 Exchanging parts
FTV1.9DE Display Box
1. Remove all copper EMC SHIELDING springs mounted around the display [6]. 2. Now flip the complete Display Box and place it with the Plasma Display down on a foam cushion. Be 100 % sure a large foam cushion is placed underneath the PDP, as it will drop about 10 mm after removing its fixation screws ! ! 3. Disassemble metal rear cover (for a description see Chapter 1.1 'Introduction').
PDP Discharge PDP Limesco
Personal notes
FOA
M CU
SHIO
N
1
FD173 FD171
4 2 5 3 3
PD3
CN24
CN23
CL 96532069_145.EPS 120899
Figure 2-15
1. Disconnect the following cables: Cables coming from connectors CN23 and CN24 of the PDP DISPLAY panel [3] (for easiest access lift the PDP DISCHARGE panel from its fixations [2]). Flat cable on connector PD3 of the PDP LIMESCO panel [4]. Also remove the ferrite 'flat cable shield' completely by unlocking its fixations [5].
1 1 2 2 2 2 3 1 1
CL 96532069_146.EPS 120899
Figure 2-16
1. Now remove the 8 large screws which hold the PDP: 4 screws are located at the top: they also hold the aluminium wall mount [1]. The other 4 are located at the bottom: the 2 outer screws are hidden behind panels. Therefor unscrew the VS/VA SUPPLY and the PDP-LIMESCO panel (grey panels) [2]. 2. Lift encasing from PDP and replace PDP [3].
FTV1.9DE Display Box
3. Block diagram
11
For the block diagram see Service Manual chapter 6. The power is supplied by the VsVa supply (which is an LLC converter). The Pre-conditioner delivers the input voltage of 380 V.
3. Block diagram
Personal notes
The output voltages of the VsVa supply are: · Va: 55 V + 5 * Vra (Vra varies between 0 and 2 V). · Vs: 165 V + 10 * Vrs (Vrs varies between 0 and 2 V). · +5 V, 8.6 V and the +/- V_audio. The controls located on the µP panel, which is a panel on the AV Control panel, are activated by the keyboard on the Front I/ O and RC5 signals from the remote control receiver on the LED panel. Audio signals coming from the YUV Y/C panel or from the AV Control are selected and processed at IC7940 (TDA9860). The outcoming L/R signals are filtered (HPF) and corrected for low frequency by the DBE-circuit, before they are fed to the Audio amplifier. CVBS signals (BNC connector or CINCH) at the YUV Y/C panel are first passed through a comb-filter IC7012. The output signals (Y and C) of IC7012 and the Y/C signal from the SVHS connector are selected by IC7010. The output Y/C are fed to YUV/RGB matrix IC7013 (TDA8854). The YUV signals (CINCH) are processed separately in a RGB matrix and transferred to IC7013. The selected RGB_YC output signals from IC7013 are fed to the AV Control panel. RGB signals coming from the Receiver Box or PC, the normal RGB_VGA or separate RGB_YC signals are selected by the source select switch (IC7360). The output signals are fed to the video control IC7300. The RGB output signals from IC7300 are buffered and transferred to the PDP LIMESCO panel. Here the signals are prepared and processed (gamma correction; filtered; digitised by an ADC), buffered and fed to the display. OSD-signals are added on the display via the PDP LIMESCO IC. RGB_VGA input signal are buffered and passed through to the VGA-out connector.
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4. Service modes 2.2 Exchanging parts
Service modes
FTV1.9DE Display Box
For the FTV1.9, the Monitor can be used in two applications. · A stand-alone configuration, a separate device which can also be sold and serviced separately. · TV configuration, where the monitor is combined with the Ebox.
4.
Personal notes
The monitor, as a stand-alone unit, can be serviced by using a test pattern coming from the PDP-LIMESCO panel on the rear of the monitor itself or via a PC/laptop by using ComPair via the ComPair connector. In this chapter the following paragraphs are included: 1. Test points 2. Dealer Service Tool (DST) 3. Service Modes 4. Error code buffer and error codes 5. The "blinking LED" procedure 6. Fault-finding tips 7. ComPair
FTV1.9DE Display Box
4. Service modes 4.1 Test points
13
The FTV1.9 chassis is equipped with test points in the service printing. These test points are referring to the functional blocks: · A1-A2-A3, etc.: Test points for the Audio amplifier (A) · C1-C2-C3, etc.: Test points for the AV control circuit (AVC) · FD1-FD2-FD3, etc.: Test points for the VsVa supply (FD1FD2) and the PDP discharge panel · L1-L2-L3, etc.: Test points for the PDP LIMESCO (PD1PD9) · PR1-PR2-PR3, etc.: Test points for the Pre-conditioner (PR1-PR3) · Y1-Y2-Y3, etc: Test points for the Y/C YUV monitor panel (UY1-YC4)
4.1 Test points
Personal notes
Measurements are performed under the following conditions: Video: colour bar signal; Audio: 3 kHz left, 1 kHz right
14
4. Service modes 4.2 Dealer Service Tool (DST)
Dealer Service Tool (DST)
FTV1.9DE Display Box
For easy installation and diagnosis the dealer service tool (DST) RC7150 can be used. When there is no picture (to access the error code buffer via the OSD), DST can enable the functionality of displaying the contents of the entire error code buffer via the blinking LED procedure, see also paragraph 5.5. The ordering number of the DST (RC7150) is 4822 218 21232.
4.2
Personal notes
Installation features for the dealer The dealer can use the RC7150 for programming the TV-set with pre-sets. 10 Different program tables can be programmed into the DST via a GFL TV-set (downloading from the GFL to the DST; see GFL service manuals) or by the DST-I (DST interface; ordering code 4822 218 21277). For explanation of the installation features of the DST, the directions for use of the DST are recommended (For the FTV1.9 chassis, download code 4 should be used). Diagnose features for service FTV1.9 sets can be put in two service modes via the RC7150. These are the Service Default Mode (SDM) and the Service Alignment Mode (SAM).
FTV1.9DE Display Box
4. Service modes 4.3 Service Modes
Service Alignment Mode (SAM)
15
Below described sequence is only valid for the "Monitor Only Configuration". When a Receiver box is connected to the Display Box (TV Configuration), please check chapter 4 in the Training Manual of the Receiver Box.
4.3 Service Modes
Service Default Mode (SDM) The purpose of the SDM is: · Provide a situation with predefined settings to get the same measurements as in this manual. · Access to the error buffer via the blinking LED procedure. · Inspect the error buffer. · Possibility to overrule software protections via the service pins (caution: override of software protections! ). Entering the SDM: · By transmitting the "DEFAULT" command with the RC7150 Dealer Service Tool (this works both while the set is in normal operation mode or in the SAM). · By pressing on a standard RC the following sequence 0, 6, 2, 5, 9, 6 followed by the "MENU" key. · By short-circuiting the SDM pin on the µP panel. In the SDM the following information is displayed on the screen: -------------------------------------------------------------F19DBC X.Y_12345 (1) LLLL (2) SDM (3) ERR 02 01 14 ## ## ## ## ## ## ## -------------------------------------------------------------Explanation notes/references: (1) Software identification of the main micro controller (F19DBC X.Y_12345) · F19D is the chassis name for FTV1.9 display · B is the region identification · C is the language cluster · X = (main version number) · Y = (subversion number) · ##### are 5 digits of the Serial number (2) "LLLL" Normal display operation in hours (3) "SDM" To indicate that the TV set is in the service default mode (4) "ERR 02 01 14 ## ## ## ## ## ## ##" This line shows the contents of the error buffer (max. 10 errors). The last error that occurred is displayed at the most left position. When less then 10 errors have occurred the rest of the line is empty. When the errorlist is empty " No errors" is displayed. No duplicate errors. Exit the SDM: Push the "Standby" button on the Remote Control. The SDM sets the following pre-defined conditions: · Volume level is set to 25% (of the maximum volume level). · Linear Audio and Video settings are set to 50%. · Colour temperature is set to normal. The following functions are "overruled" in SDM since they interfere with diagnosing/repairing a set · Video blanking. · Slow demute. · Anti-ageing. · Automatic switch to "Standby" when H- and/or V-sync signals are lost. All other controls operate normally.
The purpose of the SAM is to align and or adjust settings. For recognition of the SAM, "SAM" is displayed at the top of the right side of the screen Entering the SAM-menu: · By pressing the "ALIGN" button on the RC7150 Dealer Service Tool · Standard RC sequence 062596 followed by the "OSD" button. · By short-circuiting the SAM pin on the µP panel (Caution: override of software protections ! ! ) In the SAM the following information is displayed on the screen: -------------------------------------------------F19DBC X.Y_12345 SAM ERROR## ## ## ## ## WHITE POINT PDP TEST PATTERN [ON/OFF] STORE RESET ERROR BUFFER -------------------------------------------------The menus and submenus White point The white point sub menu contains the following items: · RED · GREEN · BLUE · COLOUR TEMPERATURE PDP Test pattern By selecting this item, all OSD disappears from the screen. The screen now changes from light grey to dark grey in a slow regular rhythm. One can so easily check if all pixels of the monitor are correct. Store The change values are stored in the NVM. Reset Error Buffer This option will reset the error buffer. Exit the SAM: Push the "Standby" button on the Remote Control. SAM menu control: Menu items can be selected with the "UP" or "DOWN" key. Entry into the selected items (sub menus) is done by the "LEFT" or "RIGHT" key. The selected item will be highlighted. With the same "LEFT/RIGHT" keys, it is possible to increase/ decrease the value of the selected item. Return to the former screen by pushing the "MENU" button. The item values are stored in NVM if the sub menu is left.
16
4. Service modes 4.3 Service Modes
FTV1.9DE Display Box
Customer Service Mode (CSM) Display FTV1.9 monitors are equipped with the "Customer Service Mode" (CSM). CSM is a special service mode that can be activated and de-activated by the customer, upon request of the service technician/dealer during a telephone conversation in order to identify the status of the set. This CSM is a 'read only' mode, therefore modifications in this mode are not possible. Entering the Customer Service Mode. · By pressing on RC03333/01 the following sequence : Picture, sound, cursor up, cursor down, cursor left, cursor right followed by the button (MUTE) Exit the Customer Service Mode. · pressing the "MENU" or any key on the Remote Control handset (except "P+" or "P-") · switching off the TV set with the mains switch. All settings that were changed at activation of CSM are set back to the initial values The Customer Service Mode information screen The following information is displayed on screen: -------------------------------------------------CUSTOMER SERVICE MENU · Software version F19DBC X.Y_#####) · Code 1: contains the last 5 error codes · Code 2: contains the first 5 error codes with the last received error at the most left-hand side. · Service unfriendly modes --------------------------------------------------
Personal notes
FTV1.9DE Display Box
4. Service modes 4.4 Error code buffer and error-codes
17
4.4
Error code buffer and error-codes
Error-nr 1 2 3 4 5 6 7 8
Type of Error +5V 8V6 Fan_prot Over-temp_prot DC_prot Over_voltage_prot Vrr Power_OKE
Possible defect/cause +5V pin at uP is low. 8V6 pin at uP is low Gives an indication that 1 or more FAN(s) does not function, or that 1 or more fan control circuits is defect Temperature at the heatsink of the VsVa supply or the Preconditioner is too high Audio-amplifier IC, its supply or the Audio amplifier is defect Vs or Va supply voltage is too high Powersupply of the display is not correct. Ignorance of the signal during startup by the software. Power supply or modules that uses this voltage. If this signal is NOT activated means that all supply voltages are available (exception Audio supply ) NVM IIC bus is not correct Slow IIC bus is not correct No acknowledge of Audio controller No acknowledge of Video controller No acknowledge of OSD Generator No acknowledge of Limesco No acknowledge of I/O Expander No acknowledge of NVM Fault in the communication
ch5-table1-mon.eps 041099
9 10 11 12 13 14 15 16 17
Blocked NVM IIC bus Blocked slow IIC bus TDA9860 TDA4885 MC141585 uPD93687GD-LBD PCF8574AT NVM Communication
Figure 1 : Error-code list of the D-box
The error code buffer contains all errors detected since the last time the buffer was erased. The buffer is written from left to right. In case of non-intermittent faults, clear the error buffer before starting the repair to prevent that "old" error codes are present. If possible check the entire content of the error buffers. In some situations an error code is only the RESULT of another error code (and not the actual cause). Note: a fault in the protection detection circuitry can also lead to a protection The error code buffer will be cleared in the following cases: · exiting SDM or SAM with the "Standby" command on the remote control · transmitting the commands "DIAGNOSE-9-9-OK" with the DST. The error buffer is not reset by leaving SDM or SAM with the mains switch. Examples: ERROR: 0 0 0 0 0 : No errors detected ERROR: 6 0 0 0 0 : Error code 6 is the last and only detected error ERROR: 5 6 0 0 0 : Error code 6 was first detected and error code 5 is the last detected (newest) error
Personal notes
18
4. Service modes 4.5 The "blinking LED" procedure
The "blinking LED" procedure
FTV1.9DE Display Box
The contents of the error buffer can also be made visible through the "blinking LED" procedure. This is especially useful when there is no picture.
4.5
Personal notes
There are two methods: · When the SDM is entered, the LED will blink the contents of the error-buffer. Error-codes = 10 are shown as followed. A long blink of 1second which is an indication of the decimal digit, followed by a pause, followed by n short blinks. When all the error-codes are displayed, the sequence is finished with a led display of about 3 seconds. The sequence starts again. · With the DST all error codes in the error buffer can be made visible. Transmit the command: "DIAGNOSE x OK" where x is the position in the error buffer to be made visible x ranges from 1, (the last (actual) error) to 10 (the first error). The LED will operate in the same way as in the previous point, but now for the error code on position x. Example: Error code position 1 2 3 4 5 Error buffer: 12 9 5 0 0 · after entering SDM: 1 long blink of 1 sec. + 2 short blinks pause - 9 short blinks - pause - 5 short blinks - pause long blink of 3 sec. --etc. · after transmitting "DIAGNOSE- 1- OK" with the DST: 1 long blink 2 short blinks - pause - 1 long blink + 2 short blinks etc. · after transmitting "DIAGNOSE- 2- OK" with the DST: blink (9x) - pause - blink (9x) - etc. · after transmitting "DIAGNOSE- 3- OK" with the DST: blink (5x) - pause - blink (5x) - etc. · after transmitting "DIAGNOSE- 4- OK" with the DST: nothing happens
FTV1.9DE Display Box
4. Service modes 4.6 Protections
19
All protections are handled by the hardware. The SW will only monitor the hardware to generate error codes for the service. The hardware switches to protection when one of the following protections becomes active: FAN_PROT, OVER_TEMP_PROT, DC_PROT, OVER_VOLTAGE_PROT and Vrr. When 1 of these protections occur, the HW will switch the set to STANDBY. The error must be read out by the microprocessor and the error code must be generated. The microprocessor keeps the set in STANDBY and starts the blinking red led. It is not allowed to start up as long as the protections are present. For the error code generation, the following levels of the A/D converter are defined:
4.6 Protections
Personal notes
Input voltage at A/D converter [V]: < 0.300 V 0.3 < V < 1.875 1.875 < V < 2.813 2.813 < V < 3.75 3.75 < V < 4.688
Sort protection: No protection FAN_PROT OVER_VOLTAGE_PROT OVER_TEMP_PROT DC_PROT
20
4. Service modes
FTV1.9DE Display Box
DISPLAY SUPPLY MODULE
LLC Converter
Vs
OVP SENSE 380 VDC
LLC Control
Error Amp.
Vrs
Delay Vs Va Voc ok
Vrr Vrr to µP
POWER OK 17V TEMP ptc ptc Speed Control
POWER OK
Fans (1-5)
ptc
Protection Circuit
Vs OVP Va OVP Fan Protect
FAN PROTECTION
FAN PROT PROT-FAN (1-5)
DC PROT (Audio)
AND
-1 17V DC_DC Converter
STBY +5V Vcc
LLC Converter
5V OVP
+8V6 +/- V Audio Va OVP SENSE Error Amp.
LLC Control
Vra
5VSTBY-SWITCHED On/Off Switch 5VSTBY
TO µP
CL 96532069_112.eps 240899
FTV1.9DE Display Box
4. Service modes 4.6 Protections
21
POWER_OKE For ease of start-up and fault diagnosis a POWER_OKE signal is generated. The signal is high when the voltages that are sensed are in the right level. This signal is mixed with signals derived from Vs and the Va. The POWER_OKE signal will be high when simultaneously: 5V = 5V 17V >12.8V Vs >135V Va > 45V In all other cases the output is low.
Personal notes
22
4. Service modes 4.6 Protections
FTV1.9DE Display Box
5VSTBY-SWITCHED
VA
5VSTBY-SWITCHED
VS 5VSTBY-SWITCHED
VCC 3135 7371 VDD 7301 7302 7370 2134 +5V 3138 2132 2135 3134 SUPPLY-ON [PR3] 3136 3384
3033 3058 3133 7112 3137 7114 3394 AA FD1 [C-14] 7113 3385 7341
3035
3036
7016 7012
3034
2037
3037
7013 2038 3386 3038 2032
CONNECTOR FD06-12
3323 5VSTBY-SWITCHED CONNECTOR D09 5 TEMP 3331 7337 DC 3332 3 2 4 5VSTBY-SWITCHED 3333 8 7330-A 7332 3380 7331 3339 7314 4 7340 17V 7321 17V 5VSTBY-SWITCHED PROT-FAN 1-6
6371
7315 7316-7321
3039 PROTS 7003 7338 7103
3139
PROTECTION-STATUS 7333 7339 7103
3379
3378
3011
3111 7101-PIN10
7001-PIN10
CL 96532058_086.eps 280999
Protection structure The protection structure of the FTV1.9 D-box is shown at figure above. The FTV1.9 monitor has one microprocessor, which is situated on the AV-control panel and is supplied by the 5V standbysupply. The microprocessor is even active when the set is switched to standby. The microprocessor controls the "supplyon" line which switches first relay 5680 and then relay 5690. In de standby-mode or the protection-mode the "supply-on" line is "low" and both both relays are switched off. The preconditioner is disconnected from the mains. The potections of the FTV1.9 monitor can be divided into 5 subgroups: Fan_prot Over_temp_prot DC_prot Over_voltage_prot Vrr For the Fan-, Over_temp, DC and the Over_voltage protections the signals for the µP are latching, using the 5Vstby_switched for powering the circuits permanently. The µP has sufficient time for diagnosis and for storing the error-codes in the NVM. Vrr, which is an indication of the powersupply of the display is correct, is directly fed to the µP.
Personal notes
FTV1.9DE Display Box
4. Service modes 4.6 Protections
23
Signal line "PROTECTION STATUS" and errorcodes When one of the protection mechanism is triggered, the 5Vstby-switched is connected via a saturated transistor and a pre-defined resistor to signal line "protection status", which is connected to the µP. Signal line "protection status" is connected to ground via resistor R3378 and 3379. For each seperate fault condition mechanism we get a pre-defined voltage at the µ. This results in the following table
Protection- Series Voltage at "protection- Errormode resistor status" line code
Connecting PROTS to ground, will start a current flow through opto-coupler diode 7103 and the opto-coupler transistor connects supply voltage Vcc2 to the fault input ( pin 10 ) of IC 7101. When the voltage at pin 10 exceeds 1.0V, IC7101 stops oscillating. The Va-supply stops functioning. To continue the signal flow, go to the right upper corner of schematic FD2. Connecting PROTS to ground also results in a current flow through the opto-coupler diode of 7003. The optocoupler transistor connects supply voltage Vcc1 to the fault input ( pin 10 ) of IC 7001. When the voltage at pin 10 exceeds 1.0V, IC7001 stops oscillating. The Vs-supply stops functioning. Vs and Va protection Va protection When this protection is activated, the Va- and Vs power supply are shut down. The set is switched to the standby mode and error-code 4 is stored in the NVM. When the Va-supply exceeds the 68V, regulator 7112 is triggered and will switch on T7113. Capacitor 2132 is charged via the 5Vstby-switched and will trigger thyristor 7114, which will switch on T7341. The voltage "protection status" is now determined by the voltage dividing of R3386 and resistor R3378 and 3379. ( neglect the Vce of 0.2V of T7341 ). See schematic FD2. The presence of the voltage at "protection status" line will eventually reset the VsVa-supply. For more info see subparagraph - Reset of the VsVa-supply. Vs protection When this protection is activated, the Vs power supply is shut down. The set is switched to the standby mode and error-code 4 is stored in the NVM. When the Vs supply exceeds the 198V, regulator 7012 is triggered and will switch on T7016. Capacitor 2032 is charged via the 5Vstby-switched and will trigger thyristor 7013. Thyristor 7013 is fired and connects signal Aa to ground. To follow the signal flow, go to the right upper corner of schematic FD1. When signal Aa is shorted to ground, T7341 is switched on. The voltage "protection status" is now determined by the voltage dividing of R3386 and resistor R3378 and 3379. ( neglect the Vce of 0.2V of T7341 ). See schematic FD2. The presence of the voltage at "protection status" line will eventually reset the VsVa-supply. For more info see subparagraph - Reset of the VsVa-supply. Temperature Protection When this protection is activated, the Va- and Vs power supply are shut down. The set is switched to the standby mode and error-code 5 is stored in the NVM. When the temperture of the heatsink on the Preconditioner panel or on one of the 2 heatsink on the VsVa panel exceeds the 110°C, the PTC resistance increases drastically. The voltage at pin 3 of IC7330 will drop and the output of 7330 will do the same. The current flow through opto-coupler diode 7331 results also in a current flow through the opto-coupler transistor and will trigger thyristor 7332. The fired thyristor switches transistor 7337 on. The voltage "protection status" is now
None Fan_prot Vs or Va_prot Temp_prot DC-prot Vrr
----1K 470 220 68 ------
< 0.3V 0.30V < Vprot < 1.90V 1.90V < Vprot < 2.80V 2.80V < Vprot < 3.75V 3.75V < Vprot < 4.7V ------
none 3 4 5 6 7
Protection signal Vrr coming from the PDP, to indicate that the powersupply is ok or not ok ( "1" or "0" ) is directly connected to the µP. Error-code 7 is stored in the NVM and the set is switched to standby. When one of the protections is activated, the power supplies of the Vs and Va are shut down and the set is switched to standby. Fan protection When this protection is activated, the Va- and Vs power supply are shut down. The set is switched to the standby mode and error-code 3 is stored in the NVM. The fan voltage is powered by 17V, but clamped to 12V to prevent damage. In order to be able to verify whether the fans are running, a fault detection circuit is implemented for each of the 6 fans. A running fan gives pulses in the same speed as the rotation of the blades. The circuit uses these pulses to trigger the discharge of an elcap. The elcap is continuously charged through a resistor. Example : Capacitor C2319 is charged through R3356 and at every pulse discharged by T7322. When fan 6 is blocked, C2314 is charged via D6326 en triggers thyristor 7315, because C2319 is no longer discharged via T7322. The current now flows from the 5Vstby-switched via resistor 3383 and 3325 driving transistor T7321 into saturation. The voltage "protection status" is now determined by the voltage dividing of R3323 and resistor R3378 and 3379. ( neglect the Vce of 0.2V of T7321. ). Reset of the VsVa-supply. Transistor T7339 is shorted now by the presence of the "protection status" signal. T7339 connects resistor R3376 and R3389 to ground, switching on T7338. Thyristor 7333 is now triggered, shorting signal PROTS to ground. To follow the signal flow, go to the right upper corner of schematic FD1.
24
4. Service modes 4.6 Protections
FTV1.9DE Display Box
determined by the voltage dividing of R3339 and resistor R3378 and 3379. ( neglect the Vce of 0.2V of T7337 ). The presence of the voltage at "protection status" line will eventually reset the VsVa-supply. For more info see subparagraph - Reset of the VsVa-supply. DC Protection - Audio Amplifier When this protection is activated, the Va- and Vs power supply are shut down. The set is switched to the standby mode and error-code 6 is stored in the NVM. In case of a fault in the Audio amplifier or when a DC voltage appears on the speaker output, a signal called DCPROT is generated. See schematic FD2 - F7. In case of a fault, thyristor 7314 is triggered and switches on T7340. The voltage "protection status" is now determined by the voltage dividing of R3380 and resistor R3378 and 3379. ( neglect the Vce of 0.2V of T7340 ). The presence of the voltage at "protection status" line will eventually reset the VsVa-supply. For more info see subparagraph - Reset of the VsVa-supply. Vrr - PDP supplies Vrr is a logical signal ( "high" in normal circumstances ) that comes from the PDP. It's purpose is to trigger the switch off of the Pre-conditioner supply in case Vrr becomes "low" , to trigger the shutdown of the VsVa supply and to initialise that errorcode 7 is stored in the NVM. When signal Vrr becomes "low", see FD1 - F13, the output of IC7301-B becomes "high". This results in two actions. It will trigger thyristor 7302 and short signal PROTS to ground. This results eventually in a reset of the VsVa supply. Switching on T7371, which again switches on T7370 via the 5Vstby-switched supply. Signal-line "supply-on" is now grounded. This results in switching off relay 5680 and 5690, disconnecting the mains from the pre-conditioner. The standby supply( 5Vstby-switdhed ) is still functional.
Personal notes
FTV1.9DE Display Box
4. Service modes 4.7 Alignments
25
4.7
Alignments
Electrical Alignments Pre-conditioner +5Vstby (PR3) Connect a voltmeter to capacitor C2510 (PR2). With the aid of R3504 adjust the voltage to 5.2 V +/- 50 mV. Va-supply (Addressing of the PDP - FD1) De-activated the PDP. Connect a voltmeter to capacitor C2120 (FD1). With the aid of R3126 adjust the voltage to 55 V +/- 0.5 V. Vs-supply (Sustain pulses - FD2) De-activated the PDP. Connect a voltmeter to capacitor C2020 (FD2). With the aid of R3026 adjust the voltage to 165 V +/- 0.5 V. Software Alignments See chapter 4.3.2. "Service Alignment Mode (SAM)".
Personal notes
26
5. Preconditioner 5.1 Caution
Preconditioner5.1Caution
FTV1.9DE Display Box
When repairing the Preconditioner supply the hidden mainsswitch must be used to disconnect the monitor from the mains. The pre-conditioner and the VsVa supply remains under tension if the mains-cable is still connected to the mains socket and the mains switch is NOT pressed.
5.
Personal notes
FTV1.9DE Display Box
5. Preconditioner 5.2 Introduction
27
5.2
Introduction
MAINS IN
MAINS FILTER
PRECONDITIONER
380V
+12VSB
TEMP PRECON
Filtered Mains Voltage +5VSTBY +5VSTBY Switched SUPPLY ON POR
STANDBY SUPPLY
CL 96532069_119.eps 300999
The preconditioner module is designed for the FTV 1.9. It is the interface between the mains input and the VsVa panel of the monitor. The advantage of a preconditioner in this application is: · reduction of mains harmonics to legal limits · lower mains current for the same output power. · regulated output for the mains isolated power supplies following the preconditioner module. The preconditioner consists of 3 functional sub-modules. 1. Mains filter 2. Main supply 3. Stand-by supply
Personal notes
28
5. Preconditioner
FTV1.9DE Display Box
5.3
General description.
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FTV1.9DE Display Box
5. Preconditioner 5.3 General description.
29
The mains is fed through the mainsfilter to reduce commonand differential noise. The mains switch - 1004, is added to disconnect the mains input from the pre-conditioner. This ON/OFF relay has to be switched manually, while the other relay is controlled by the SUPPLY ON signal. This signal is low if the standby signal is high, or one of the protections is activated. The standby supply is a separate power supply to reduce power consumption of the Flat TV set in standby mode. The bridge rectifier rectifies the mains voltage and is applied to a differential mode filter- 5605 for EMI requirements and then to the preconditioner. The preconditioner has an output voltage of 380V, controlled by the PCF controller (MC3336P) which is independent of the mains input. The output voltage of 380V is delivered to the Vsand Va supply. A PTC is connected to the heatsink of the MOSFET, which puts the set in protection, by activating an Opamp on the VsVa panel, when the temperature exceeds a safety limit.
Personal notes
30
5. Preconditioner 5.4 Mainsfilter
Mainsfilter
FTV1.9DE Display Box
5.4
MAINS FILTER
1402 F204 F208 F209 1401 F207 PR1 0314
1 2 3
I200
3404 220R
DSP
AC inlet
LIVE_IN GROUND_IN NEUTRAL_IN
2404 I202
V 2322595
2406 I203 47p
2407 RES
I201 F200 4 3 F211 PR30
470p 3402 4M7 2402
1400
47p 5401 4 CU28D3 3 I205
1004 2 1
3401 1M
1 5400 2
2400 470n 3400
2401
3
4
I204
2
1
220n
5402 4 CU28D33
2
RES
1
PR31
F210 F212 F201
F202 I206 PR3
3403 4M7
2403
470p
2405
PR2
F203
GNDEARTH2
GNDEARTH2
GNDEARTH2
GNDEARTH2
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The AC power is fed to the mainsfilter (0314). A mains switch has been added to switch off the mains while repairing the set. The first filter around coil 5400 is to differential mode filter to reduce H.F. noise produced by the FTV. A second filter around coil 5401 is a common mode filter to reduce noise from the VS/VA supply and the preconditioner itself. Together with capacitors 2400 en 2401, coil 5401 works as a lowpass filter. A second common mode filter is made around coil 5402 and capacitor 2407. Resistor 3400 is a high energy VDR. The advantage of this VDR is that it can handle 380VAC without risk of fire. The mains filters are damped by a spark gap / resistor combination to prevent damage in the mains isolated power supplies of the monitor. Ground leads of the AC inlet and outlet are filtered with a toroid inductor. This is needed to fulfil EMC regulations without the need of a special and expensive filtered mains cord. Resistor 3401 discharges the X capacitors after the mains is disconnected.
Personal notes
FTV1.9DE Display Box
5. Preconditioner 5.5 Standby supply
31
5.5
Standby supply
STANDBY SUPPLY
6503 BYD33D 2505 4u7 2506 100p 1 2 3 4 5
5500 CE165T 9 8 7 6 2507 100p 6504 4u7 BYD33D 2508 PR8 +12VSB PR10 PR9
PR6 3508 DF06M 1 RES 2503 2501 3 6500 4 PR7 3506 10R GNDHOT1 1R 22u GNDHOT1
1500
2500
RES
2
6505 2510 BYV27-200 2509 100p 3501 3502 33K 7500 TOP 210 9667 5 SOURCE 6 N/C 7 N/C 8 DRAIN
CONTROL 4 N/C 3 N/C 2
470R 7501 TCDT1102G 3500 470R 9668 100n 2504 47u
3 1
BZT03-C
+5VSTBY_SWITCHED 6501 9520
1m
+5VSTB
3505 33n 3503 3504 1K 3K9
3520
3521
39K
1K
BZT03-C
6502
9521
7521 BC547B 2520
2513
7520 MC34064P2 1 RESET_ IN
CONTROL 1
TL431CLP 7502
2
GNDHOT1
+5VSTBY
GND
GNDHOT1
3
2511
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The standby supply is a separate power supply to reduce power consumption of the Flat TV set in standby mode. It has 2 mains isolated outputs: · +5VSTBY for the microprocessor of the monitor and to power the ON/OFF relay in the preconditioner. · +12VSB to power the inrush relay of the preconditioner. The AC input is applied through fuse 1500, rectified by bridge 6500 and smoothed by capacitor C2503. The stand by supply is build around the TOP Switch TOP210. The frequency is fixed to 100 kHz. The voltage is controlled by regulating the input current at pin 4 of the TOPSWITCH via the opto-coupler transistor 7501. More current means a smaller duty cycle. The 5VSTBY can be adjusted by resistor 3504. If the 5VSTBY increases, pin 3 of 7502 also increases. The current through the opto-coupler diode 7502 will increases and so the current through the optocoupler transistor 7502. An increase of the input current at pin 4 of the 7500 will decrease the duty cycle. As a result the 5VSTBY will decrease again. Diodes 6501 en 6502 are added to protect the input of the TOPSWITCH against mains spikes.
Personal notes
4K7
32
5. Preconditioner 5.6 POR circuit
POR circuit
FTV1.9DE Display Box
5.6
+5VSTBY >4.5V time
POR
>100ms
time
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POR will go low if the 5V-STBY is out of specification. The POR signal resets the processor (and if needed other small signal circuits) on the AV Control Board. The POR circuit is build around IC7520 (MC34064P). When starting the set the POR follows the 5VSTBY. Transistor 7521 is switched on with a certain delay defined by R3520 and C2520, and signal POR is grounded. When the 5VSTBY drops below 4.59V pin 1 7520 becomes low, transistor 7521 is switched OFF and the POR changes from "0" into "1". The microprocessor at the AV control will put the set to STANDBY.
Personal notes
6605 1N5406 6611 PR12 PR09 0310-1 1 3 5605 4 14 15 16 12 13 6606 5610 CE423D 3601 1 6 2 3n3 2610 2615 330u 2616 330u
10R
BYV29F-500 2611 1n5 2
FTV1.9DE Display Box
3600 4 +t 6608 3610 3R3 PR13 0R1 3614 0R1 3615 0R1 3613 0R1 3616 6609 2600 1n 2 1u 1u 2605 1u 2604 2606 6600 3 GBU8 2607 2 4
1R
+t
7610 STY34NB50
10R
G4W 1 BZT03-C 1u 3602
t
G4W 1N4148 BC369 7608
2 B57464 2601 1 1n
4
4
100MHZ
1N5406
1 CU20 2
5612
380V
3 PR14
HOT_GROUND
1
3
3
12R
0315 0316 3663 HEATSINK HEATSINK Vref 5 1 2 1K 3653 1K 3668 3 4 5 1R 100u BYD33D 1 2 3 4 6661 2663 1
3608
6 1N4148 6663
5
5
6
4
TEMP_PREC_A 3 2 7660 L7815 +t
5680
5690
BYD33D
Vref 3654 10K Vref 1M 3652 SIG1 SIG3 2656 100n 2u2
2 RD
NC1 NC2 FC VCC
6660 2664
100u
3606
9606 5 6665 PR15 SIG2
6654
TEMP_PREC_B
1N4148
3650
1M3
BC557B 7654
1 VREF
LINE
16
2652
47u
2654
3 VFB
14 13 12
3665
10K
15
BYV10-40
7650 MC33368
3641 2665 PR17 470p SIG2 6641 6662 2662
res
PR16
470R
7641 BC337-25 SIG3 6642 470u
1u 2655 SIG1 6651
6 CS 7
ZC AGND
4 COMP 5 MULT
10K
10n
3651
2651
GATE 11
1N4148 2608 100p 3667 10K
PGND 10 LEB
BYV10-40
BYV10-40 6640
9
5. Preconditioner
PRECONDITIONER
8
BYV10-40 3666
3642 100R 2640 3670 750K 100R RES 470p 6664 2666 100p RES 7640 BSN304 2
2653
+12VSB BYV10-40
1n
BYV10-40 6652
+5VSTBY_SWITCHED 10K 100u 3684 6691 BYD33D
2683
3640
6681
BYD33D
3683 10K 6690 BYD33D BC557B 7684
6680
BYD33D
3680 PR18 3690 10K 7690 BC547B
2
10K
1
4K7
3
CL 96532069_088.eps 040899
3685 4K7
7681 STD17N06
3682
3681
10K
3671
10K
470R
1
3
33
34
5. Preconditioner 5.7 The preconditioner
The preconditioner
FTV1.9DE Display Box
The input voltage of the preconditioner is universal, between 95 V and 264 V. The output is 380 Vdc (370 V - 390 V) to the Vs/Va module with a maximum output power of 500 W (long-term average), and a peak value of max. 1000 W during 1 minute. The preconditioner does not provide mains isolation.
5.7
Voltage regulation The output voltage (380 V) is divided by R3670 and R3671 and connected to pin 3 7650. A change of the load will adjust the duty cycle of the gate pulse at pin 11 of the supply IC to maintain the output voltage constant at 380 V. There is no need to adjust the output voltage by means of a potentiometer. Current-protection.
Starting up. The microprocessor controls the double pole by means of signal SUPPLY ON. This signal switches indirect relay 5680 via MOSFET 7681 and so enables the use of a small low voltage switch. To protect rectifier 6600 and relay 5680 the inrush current is limited to maximum 20 A by charging capacitors 2605,2606 and 2607 through 2 serial PTC's. After approx. 0.5 sec relay 5690 is activated. This relay connects an NTC in parallel with the PTC. The advantage of using an NTC is the fact that the resistance varies with current and hence mains voltage. At high mains voltage, the current is lower for the same power. Two clamp diodes 6605 and 6606 charge output capacitors C2615 and 2616 to the peak voltage of the mains input. During normal operation both diodes are blocked because of the output voltage of 380 Vdc, and will only conduct if there is a mains spike or an output dip. Capacitor 2615 and 2616 deliver via R3668 the start-up voltage at pin 16 of IC7650. After the start-up cyclus, IC7650 is supplied via auxiliary winding 1-2. Capacitor C2663 is charged during the cycle that MOSFET 7610 conducts. While MOSFET 7610 is switched off, capacitor transfers its energy via D6661 to the input of stabiliser IC7660. The output voltage of IC7660 is 15 V and is fed via D6665 to supply-pin 12 of IC7650. The slow start function is realised by the circuit consisting of transistor 7654, D6654, R3654 and C2654. Preconditioner-circuit The supply IC generates pulses at pin 11 of IC7650, referred to as SIG2. Because these pulses aren't small enough, a circuit around transistor 7640 and 7641 has been implemented. The duration of the square wave is decreased by 500 nsec. Components R3640 and C2640 set this value. A current sense coil has been used to switch ON the MOSFET when there is no energy left in the transformer. This information is fed to the controller IC7650 pin 7. In this way the dissipation is very low combined with a low EMI. The rectified mains input is connected to pin 5 of IC7650 via voltage divider R3650 and R3651. This voltage is proportional with the mains input and is used to change the duty cycle of the gate-pulses at pin 11. The MOSFET is switched OFF at very high current, up to 30 A. To reduce dissipation, this is done with high speed. Turn off driver T7608 has been added to accomplish this. When there is an error in the supply the supply-IC would like to restart. To prevent this hiccup a RESTART DELAY is build in around pin 2 7650. The delay is set by R3652 and C2625 and can be adjusted up to a few seconds. Resistor 3401 discharges the X capacitors after the mains is disconnected. This is needed to fulfil safety regulations.
The current through the FET flows also through the resistors 3613, 3614, 3615 and 3616. The voltage across these resistors are fed to pin 6 of IC7650. If the current becomes too high, then the preconditioner will turn off. A filter consisting of C2666 and R3666 avoid an unnecessary protection due to spikes. C2665 and R3665 on pin 13 determine the maximum osc. frequency. Temperature protection. PTC 3606is connected to the same heatsink as MOSFET 7610. If the temp of this heatsink exceeds a safety limit the resistance of PTC 3606 will increase dramatically. This increase will trigger an Opamp on the VsVa panel and this will switch the set to standby. This is done by resetting control IC7001 and IC7101 of the VsVa supply. The module is designed to operate at an ambient temperature from 0° to 45°C and with forced air-cooling. For detailed info about the temperature protection, see chapter 4.6. of the TM Monitor.
FTV1.9DE Display Box
5. Preconditioner 5.7 The preconditioner
35
ûs sin st
0
/2 st
CL 96532069_151.eps 250899
Application The European Law describes a reduction of Mains harmonics for apparatus with a power consumption above 75W. Only the ground harmonics are responsible for the power transfer. The power factor should be close to 1. The solution is the Pre-conditioner. The advantages of a pre-conditioner compared to a mains input filter are: · Stable output voltage · Small · Low weight · Power factor close to 1 Out of the three basic switch mode power circuits, the upconverter was used as pre-conditioner. In the FTV1.9 an upconverter is used with discontinuous current. The switching frequency of the converter will be chosen much higher than the mains frequency (50 - 60 Hz). It is then possible to consider the supply to be constant during every high frequency period and the envelop of all voltage steps during the low frequency period approximates a half sine wave, as given in figure 7. We shall consider only one half period, in which the voltage is a sinus wave-form Every step gives a current pulse of which the amplitude is determined by the requirement that the low frequency component pulses have the shape of a half sine wave. Figure 8 shows an example.
Personal notes
36
5. Preconditioner 5.7 The preconditioner
FTV1.9DE Display Box
is (st)
0
/2 st
CL 96532069_152.eps 250899
The smooth waveform between the peaks in figure 8 can be considered as the mains input current after filtering of the high frequencies. A small low pass filter will be necessary to fulfil the interference requirements Figure 9 shows the basic circuit definition for the up-converter.
Personal notes
FTV1.9DE Display Box
5. Preconditioner 5.7 The preconditioner
37
Ls + + Us S1 uLs is1 S2
is2
+ Us -
CL 96532069_153.eps 250899
Two current values have been introduced, Is1 being the current when S1 is conducting and Is2 when the diode start conducting. The up-converter as used in the FTV1.9 is used as a semidiscontinuous mode. The MOSFET is switched on when the energy in the transformer is totally transferred to the secondary side. The circuit can be split up in 2 modes Mode 1: MOSFET is conducting - Increase of the current during ton Ul = Us = Ls * dI/ dt(Us = input voltage = Vmains rectified) dI = (Us * ton) / Ls Mode 2: Diode is conducting - Decrease of the current to zero during toff Ul = (Uc - Us) * dI / dt(Uc = output voltage = 380 Vdc) dI =((Uc - Us) * toff) / Ls During its normal operation the current increase equals the current decrease. dI (mode 1) = dI (mode 2) ton = called the duty cycle (d) ton + toff = t = switching period In both equations we find the term Ls, which can be eliminated when solving the equation. Us * ton = (Uc - Us) * toff Us * (ton + toff) = Uc * toff Uc = (Us * t) / toff Uc = Us / (1 - d) The output voltage of the preconditioner equals the input voltage when the MOSFET is continuous switched OFF, and increases while the MOSFET is switched ON.
Personal notes
38
6. VsVa supply 6.1 General
VsVa supply6.1General
FTV1.9DE Display Box
6.
GENERAL
380V 5 Vstby-sw
SUPPLIES
Vs Va 5V2 Vrs Vra
PRECONDITIONER
PDP
Vrr
5 Vstby Supply on TEMP POR
PROTECTIONS
5 Vstby-sw 5 Vstby POR 1) STBY SND-ENABLE V+ V5 VSTBY-SW FAN-SUPPLY PROT-FAN
SNDENABLE
DC PROD
AVCONTROL
8V6 5V2
AUDIO AMPLIFIER
FANS
CL 96532069_059.eps 040899
The supply delivers the power for the display of the FTV1.9, which includes the power for the PDP itself, the PDP LIMESCO panel, the AV controller and the audio power amplifiers, but not the standby voltage. Block-diagram Both Va and Vs supply circuits are based upon the LLC converter technology as used in the power supply for MG 98 TOP. The supply consists of four parts: The Vs voltage Is used to supply the power of the sustain pulses, which generate the light in the PDP. The voltage is set by a reference DC voltage (Vrs), coming from the PDP. Vs = 165 V + 10 * Vrs (Vrs varies between 0 and 2 V).
The Va supply The Va voltage is used to supply the power for driving the addressing electrodes of the PDP. The value of Va is also depending on a reference voltage (Vra) coming from the PDP. Va = 55V + 5 * Vra(Vra varies between 0 and 2 V). The Va supply also delivers several other voltages like ; · + 5 V for PDP , PDP interface panel · + 8V6 : for AV controller and video controller · +Vsnd : pos. supply for audio amplifier (+19 V) · - Vsnd : neg. supply for audio amplifier (-19 V) SUPPLY-ON signal : indicates if supplies have to switched on ; this signal is controlled by the protection circuit and the standby signal. The FAN Supply : Provides power for the cooling fans ; controlled by fan speed control circuit Protection-circuitry : Consists out of an O(ver)V(oltage)P(rotection) , Temperature protection , Fan potections, DC protection (Audio Ampl.) and UVLO (input undervoltage protection).
FTV1.9DE Display Box
6. VsVa supply 6.2 The Resonant Power Supply
39
6.2
The Resonant Power Supply
RESONANCE SUPPLY
+300v POWER BLOCK T1 7005
6007 3014
DRIVER
+
T2
6008 3017
7006
FEEDBACK
VCC VAUX
FASE
FAULT INPUT CONTROL-IC
SENSING
CONTROLLER
CL 96532069_061.eps 200799
Block diagram resonance supply The start-up voltage for the IC is derived from one phase, the IC starts to oscillate and alternately T1 and T2 are driven into conduction with a dead time in between. This effects that via the resonance circuit and the MOSFETS energy is stored into the transformer. The secondary voltages are rectified and smoothed, these secondary voltages is via a voltage divider fed to the optocoupler that influences the oscillator frequency of the control-IC and stabilises the secondary voltages. If the current becomes too high then the supply is switched of via the fault input of the control-IC. Advantages and disadvantages. Advantages: · High efficiency (more then 90%, other supplies 75%). · Less radiation. · Cheaper: two MOSFETS of 400 V are cheaper than one MOSFET of 600 V. · Simpler transformer construction. Disadvantages: · Very low power stand-by impossible. · Realisation + stabilisation more complex. · Optimising is limited at this moment because of the availability of IC and transformer.
Principle The LLC supply is a serial resonance power supply. The coil, resistor and capacitor form a trap at the resonance frequency Fr. The impedance is frequency dependent. The smallest impedance is at the resonance frequency, at the right side of Fr is the inductive part and the left side capacitive. In principle the resonance supply could operate at the left side or the right side of the curve, but the supply works only in the right part since higher frequencies causes minor losses. The stabilisation is realised by regulating the frequency as function of the mains voltage, the load is stabilised by influencing the series-loop. The higher the frequency the lower the output power. In practice two methods can be used: · Method 1: transformer + series coil (Lr ext) + capacitor (Cr). This has the advantage of a better optimisation, since the value of series coil can be selected individually and the power-losses are distributed among 2 components. The disadvantage is the size/price of the transformer plus coil. · Method 2: transformer with bad 'induction factor' + capacitor (Cr). This has the advantage of a smaller/cheaper transformer, but the disadvantage of a limited Lr and temperature rise due to dissipation Method 2 is realised because this is the cheaper version. where Lr: leakage induction Lh: magnetic induction
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6. VsVa supply 6.2 The Resonant Power Supply
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The coil Lr is the self-induction measured with short-circuited secondary winding (=leakage-induction); thus the worse the coupling factor of the transformer the bigger Lr. The coil Lh is the total inductance of the primary winding minus Lr.
Personal notes
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6. VsVa supply 6.3 Resonant mode controller-IC MC34067
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6.3
Resonant mode controller-IC MC34067
MC34067 Representative Block Diagram
VCC 15
50k Enable / UVLO Adjust 7.0k 9 50k 8.0V
7.0k 5.1V Reference Vref 5 Vref UVLO 4.2/4.0V Vref
VCC UVLO
Vref Q1 1 R3003 C2004 2 IOSC C2005 One-Shot RC R3004 16 Oscillator Control Current IOSO 3 R3005 One±Shot 3.1V Error Amp Clamp 9.0µA Error Amp 4.9V/3.6V 4.9V/3.6V Oscillator D1 Q2 Steering Flip-Flop Q T RQ
Output A 14 13 Power Ground
Output B 12
Q
R Fault Input 10 1.0V
Error Amp Output 6 8 Noninverting Input Inverting Input 7 Soft-Start 11
S Fault Latch
CL 96532069_062.eps 200799
As control-IC the MC34067P is used for the following reasons : · zero voltage switching · variable frequency oscillator (above 1 MHz) · precision one shot timer for the dead time · 5 V reference output · double high current totem-pole output · soft-start · wideband error amplifier · fault input (protection) The oscillator The Oscillator circuit is build around the internal OPcomparator with 2 threshold-voltages; 4.9 and 3.6 V. C2004 is first charged via transistor Q1. If the voltage across C2004 is more then 4.9 V then the output of the upper of the oscillator comparator becomes low, the NOR-port output will be high and Q1 will be blocked because the base will be shortened by Q2. C2004 will be discharged via the resistors R3003 and the oscillator control current (Iosc). If the voltage across C2004 is below the lower threshold of 3.6 V, transistor Q1 is conducting and the capacitor is charged again. The oscillation frequency is modulated by the oscillator control current. The discharge current increases when pin3 MC34067 is loaded even more; thus the lower the voltage on pin3 MC34067 the higher the oscillator control current and the higher the frequency. The maximum frequency is reached when the output of the error amp is minimal (0.1 V). Thus R3005 determines the max freq.
The minimum frequency is reached when Iosc current is zero; C2004 then discharges only via the resistor R3003. The one-shot timer The one-shot timer was developed in order to deactivate both outputs simultaneously and provides a dead time so that one output will be high. The one-shot capacity (C2005) is first charged by Q1. The one-shot period begins when the oscillator comparator is switched off by Q1. The one-shot capacity is discharged via the parallel resistance (R3004); if this voltage gets lower than the lower threshold of 3.6 V the comparator will be high and controls the flip-flop, which makes one of both outputs high. If Q1 is reconducted through the oscillator comparator (for the oscillator) the one-shot capacitor is recharged. Fault detector input At pin 10 there is a fault detector input. If this voltage reaches 1 V then the output of the op-amp is high and both drive outputs are switched off. In addition, the output of OR3 will be high via the fault latch. The output of OR3 drives Q1 so the oscillator- and the one-shotcapacitor remain charged. Via OR3 the soft-start capacitor is discharged.
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6. VsVa supply 6.3 Resonant mode controller-IC MC34067
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Soft start Due to the soft-start circuit the oscillator starts with maximum frequency. The low voltage on the soft-start capacitor (C2008) is buffered and keeps the error amp. output low (Iosc = max > Fosc = max). The capacity is charged with a current of 9 µA, the output of the buffer gets high and the error amp. input takes charge of the oscillator control current. Practical diagram The start voltage of the IC is tapped from one phase and led to pin15 of the IC. The supply IC begins to oscillate, the voltage on pin 15 is taken over by the transfer winding (pin 1 & 2 transformer). Since the transformer has a bad coupling factor the transfer winding is tangled in the secondary, though with a triple isolated wire (TRISO). Via R3026 the Vs can be adjusted and stabilised. Via the alignment/stabilisation for Vs the output voltages are also stabilised. The Vs is fed via a voltage divider to IC 7110 If the voltage at pin3 IC7110 is higher than 2.5 V a current will flow from cathode to anode. This current flows also through the secondary of the optocoupler. The voltage at pin7 of the MC34067 determines the output frequency, the higher this voltage, the higher the outputfrequency. That results that in case of increasing Vbat the voltage of pin7 increases; the frequency increases and Vs decreases. When the output voltage rises, the voltage at the reference IC 7110 also rises, which causes the current through the diode of the opto-coupler to rise. The transistor of the opto-coupler conducts more, as a result of which the voltage at pin 7 MC34067 increases. The output voltage of the error amplifier gets lower, and the current through R3005 increases. Driver stage The two secondary windings of the driver transformer are wound in opposite directions and control the two switching MOSFET's. The primary winding of the driver transformer is alternately controlled by the two totem-pole outputs of the controller. Cross-conduction of both MOSFET's is prevented by the dead time. The gate of each MOSFET is controlled via the resistors 3014/ 3017 and via the diodes 6007/6008; the transistors 7007/7008 discharge the gate faster by switching off. The diodes at the basis-emitter of 7007/7008 prevent the zener-effect of these transistors. The zener diodes at the gate-source of 7005/7006 are for ESD. C2011 and C2014 form the capacity for the series resonant circuit.
Protection against overcurrent and overvoltage The voltage at R3021 is a criterion for the current, which flows through the primary. Via C2015 and D6010 the negative information is clamped at 0.6 V. The total amplitude is rectified via D6009 and C2010 and via R3020 and TS7009 supplied to the fault input (pin 10) of the controller. When the fault input is higher than 1 V the protection is activated (= overcurrent-protection). The voltage V at R3010 is the take-over winding voltage; this voltage is also supplied to pin 10 of the controller via a voltage divider R3010/R3011 (= overvoltage protection). Soft start overcurrent protection If short-term overcurrent peaks occur the frequency is adapted. The voltage at R3021 is clamped at -0.6 V via C2015 and D6010. The total amplitude is rectified via D6011 and C2008 and supplied to the "capacitive" thyristor T7017/18 via R3012. When the voltage at the emitter of T7017 gets higher than 5 V, the soft-start capacitor is discharged, and the frequency increases as a result of which the Vs drop. If this voltage remains 5 V the supply is interrupted (hick-up). This circuit is adjusted in a way that the voltage does not drop too much if a flash occurs.
FTV1.9DE Display Box 6. VsVa supply 6.4 Voltage/current waveforms of the resonance-circuit
6.4 Voltage/current waveforms of the resonance-circuit
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Vi S1 D1 Lr Br1 S2 D2 Lp Cs
+
Cr
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The total switching time can be d