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TEA2260 TEA2261
SWITCH MODE POWER SUPPLY CONTROLLER
. . . . . . . . . .
POSITIVE AND NEGATIVE CURRENT UP TO 1.2A and 2A LOW START-UP CURRENT DIRECT DRIVE OF THE POWER TRANSISTOR TWO LEVELS TRANSISTOR CURRENT LIMITATION DOUBLE PULSE SUPPRESSION SOFT-STARTING UNDER AND OVERVOLTAGE LOCK-OUT AUTOMATIC STAND-BY MODE RECOGNITION LARGE POWER RANGE CAPABILITY IN STAND-BY (Burst mode) INTERNAL PWM SIGNAL GENERATOR
DESCRIPTION The TEA2260/61 is a monolithic integrated circuit for the use in primary part of an off-line switching mode power supply. All functions required for SMPS control under normal operating,transient or abnormal conditions are provided. The capability of working according to the "masterslave" concept, or according to the "primary regulation" mode makes the TEA2260/61 very flexible and easy to use. This is particularly true for TV receivers where the IC provides an attractive and low cost solution (no need of stand-by auxiliary power supply). See application note AN376/0490 for detailed information. PIN CONNECTIONS
TRANSFORMER DEMAGNETIZATION SENSING INPUT SECONDARY PULSES INPUT POWER TRANSISTOR CURRENT LIMITATION INPUT IS IN I MAX 1 2 3 4 5 6 7 8
BATWING DIP 16 (Plastic Package) ORDER CODES : TEA2260 - TEA2261
16 15 14 13 12 11 10 9
V CC V+ OUT
POWER SUPPLY POSITIVE OUTPUT STAGE SUPPLY POWER OUTPUT
GROUND GND GROUND GND ERROR AMPLIFIER INPUT (INVERTING) ERROR AMPLIFIER OUTPUT OVERLOAD INTEGRATION CAPACITOR E S C2
GND GROUND GND GROUND R0 C0 C1 OSCILLATOT RESISTOR
2261-01.EPS
OSCILLATOR CAPACITOR SOFT-START CAPACITOR
June 1992
1/9
TEA2260 - TEA2261
SIMPLIFIED APPLICATION DIAGRAMS Figure 1 : Master-slave Concept
AUDIO OUTPUT STAGE Muting Control
R P1 Remote Stand-by
MAINS INPUT P2 C
Synchronization
SCANNING DEVICE
VOLTAGE REGULATOR Remote Stand-by VCC
TEA2260/61 SLAVE
TEA5170 MASTER
VCC
µP
INFRA-RED RECE IVER PWM
P 1 : Output voltage adjustement in normal mode P 2 : Output voltage adjustement in stand-by
Power primary ground Secondary ground (isolated from mains)
Figure 2 : Secondary Regulation (with optocoupler)
AUDIO OUTPUT STAGE Muting Control
R P Remote Stand-by
MAINS INPUT
SCANNING DEVICE
C VOLTAGE REGULATOR
VCC
TEA2260/61
µP
VCC INFRA-RED RECE IVER
2261-03.EPS
P : Output voltage adjustement
Power primary ground Secondary ground (isolated from mains)
2/9
2261-02.EPS
TEA2260 - TEA2261
BLOCK DIAGRAM
S
7
ERROR AMPLIF LIER
VCC 16
15.7V
V+
15
+
VREF 2.49V
OVERVOLTAGE PROTECTION
VREF (2.49V)
7.4V
10.3V
-1
+
MODULATOR LOGIC
MODULATORS
AUTOMATIC BURST GENERATION
+
PRIMARY PULSES
IS LOGIC
REGULATION PULSES
LOGIC PROCESSOR
REPETITIVE OVERLOAD PROTECTION
TON(Max.) (60%) SOFT-START
OSCILLATOR
0.15V
2.55V
SECONDARY PULSE
10µ A
9
11
10
1
2
8
3
4
5
12 13
C1
R0
C0
IS IN
C2
I MAX
GND
ABSOLUTE MAXIMUM RATINGS
Symbol VCC V+ IOUT+ IOUTTj Tstg Power Supply Output Stage Power Supply Parameter V16-V4, 5, 12, 13 V15-V4, 5, 12, 13 Value 20 20 1.5 2.5 150 -40, +150 Unit V V A
o o
Positive Output Current (source current) Negative Output Current (sink current) Operating Junction Temperature Storage Temperature Range
C C
THERMAL DATA
Rth (j-c) Rth (j-a) Junction-case Thermal Resistance Junction-ambient Thermal Resistance 11 45
o o
C/W C/W
* Soldered on a 35µm, 40cm2 board copper area.
MAXIMUM POWER DISSIPATION
4 3 45 o C/W 2 1 TAMB ( oC) 0 50 100 150
2261-05.EPS
P tot (W)
3/9
2261-02.TBL
2261-01.TBL
A
2261-04.EPS
-
+
-
DEMAGNETIZATION SENSING
+
45µA
+
+
E 6
-
INTERNAL BIAS
V CC MONITORING
POSITIVE OUTPUT STAGE VCC NEGATIVE OUTPUT STAGE
CURRENT LIMITATION
+ 1.2A (Max.)
14
- 2A (Max.)
OUT
-
-
+
0.6V
0.9V
TEA2260 - TEA2261
RECOMMENDED OPERATING CONDITIONS
Symbol VCC IOUT+ IOUTIOUT+ IOUTFoper VIN ROSC COSC C1 C2 C2/C1 Tamb Parameter Power Supply Positive Output Current (source current) Negative Output Current (sink current) Average Positive Output Current Average Negative Output Current Operating Frequency Input Pulses Amplitude (Pin 2) Oscillator Resistor Range Oscillator Capacitor Range Soft-starting Capacitor Range Overload Integration Capacitor Ratio C2/C1 (C2 must be C1) Operating Ambient Temperature Min. VCC stop Typ. 12 Max. VCC max 1.2 2.0 0.6 0.6 100 4.5 150 4.7 Unit V A A A A kHz V k nF µF µF
o
70
C
ELECTRICAL CHARACTERISTICS (Tamb = 25oC, VCC =12V, unless otherwise specified)
Symbol POWER SUPPLY VCC(start) VCC(stop) Hyst VCC ICC(start) ICC VCC(max) ICC(over) Delta F F tON max AVO Fug ISC IBE VREF Starting Voltage (VCC increasing) Stopping Voltage (VCC decreasing) Hysteresis (VCC(start) - V CC(Stop)) Starting Current (VCC = 9V) Supply Current (VCC = 12V) Overvoltage Threshold on VCC Supply Current after Overvoltage Detection (VCC = 17V) 9.3 6.4 2.4 10.3 7.4 2.9 0.7 7.5 15.7 35 11.3 8.4 1.4 15 42 V V V mA mA V mA Parameter Min. Typ. Max. Unit
15 26
OSCILLATOR / PWM SECTION Accuracy (ROSC = 68k, COSC = 1nF) Maximum Duty Cycle in Primary Regulation Mode Open Loop Gain Unity Gain Frequency Short Circuit Output Current (Pin 7 connected to ground) E Input Bias Current (Pin 6) Internal Voltage Reference (connected to error amplifier input and not directly accessible) IN Input Threshold (Pin 2) IS Input Threshold (Pin 1) IN Input Bias Current IS Input Bias Current First Current Limitation Threshold Second Current Limitation Threshold Thresholds Difference V IM2 - VIM1 Lock-out Threshold on Pin C2 Capacitor C2 Discharge Current Capacitor C2 Charge Current Maximum Input Bias Current (Pin 3) 50 10 60 75 550 2 0.08 2.49 70 % % dB kHz mA µA V
ERROR AMPLIFIER SECTION
2.34
2.64
INPUT SECTION VIN VIS IBIN IBIS VIM1 VIM2 VIM VC2 IDC2 ICC2 IBI(max) 4/9 0.6 0.85 0.15 0.3 0.4 600 900 300 2.55 10 45 0.2 1.2 V V µA µA mV mV mV V µA µA µA
CURRENT LIMITATION SECTION 558 837 2.25 642 963 2.85
2261-04.TBL
2261-03.TBL
10 1.5 20 0.47 0.047 0.047 1 -20
2.5
1 1
TEA2260 - TEA2261
GENERAL DESCRIPTION The TEA2260/61 is an off-line switch mode power supply controller. The synchronization function and the specific operationin stand-by mode make it well adapted to video applications such as TV sets, VCRs, monitors, etc... The TEA2260/61 can be used in two types of architectures : - Master/slave architecture. In this case, the TEA2260/61 drives the power transistor according to the pulse width modulated signals generated by the secondary located master circuit. A pulse transformer provides the feedback (see Figure 1). - Conventional architecture with linear feedback signal (feedback sources : optocoupler or transformer winding) (see Figure 2). Using the TEA2260 /61, the stand-by auxiliary power supply, often realized with a small but costly 50Hz transformer, is no longer necessary. The burst mode operation of the TEA2260/61 makes possible the control of very low output power (down to less than 1W) with the main power transformer. When used in a master/slave architecture, the TEA2260/61 and also the power transistor turn-off can be easily synchronized with the line transformer. The switching noise cannot disturb the picture in this case. As an S.M.P.S. controller, the TEA2260/61features the following functions : - Power supply start-up (with soft-start) - PWM generator - Direct power transistor drive (+1.2A, -2.0A) - Safety functions : pulse by pulse current limitation, output power limitation, over and under voltage lock-out. S.M.P.S. OPERATING DESCRIPTION Starting Mode - Stand By Mode Power for circuit supply is taken from the mains through a high value resistor before starting. As long as VCC of the TEA2260/61 is below VCC start, the quiescent current is very low (typically 0.7mA) and the electrolytic capacitor across VCC is linearly charged. When VCC reaches VCC start (typically 10.3V), the circuit starts, generating output pulses with a soft-starting. Then the SMPS goes into the stand-by mode and the output voltage is a percentage of the nominal output voltage (eg. 80%). For this the TEA2260/61 contains all the functions required for primary mode regulation : a fixed frequency oscillator, a voltage reference, an error amplifier and a pulse width modulator (PWM). For transmission of low power with a good efficiency in stand-by, an automatic burst generation system is used, in order to avoid audible noise. Normal Mode (secondary regulation) The normal operating of the TV set is obtained by sending to the TEA2260/61 regulation pulses generated by a regulator located in the secondary side of the power supply. This architecture uses the "Master-slave Concept", advantages of which are now well-known especially the very high efficiency in stand-bymode, and the accurate regulation in normal mode. Stand-by mode or normal mode are obtained by supplying or not the secondary regulator. This can be ordonnered for exemple by a microprocessor in relation with the remote control unit. Regulation pulses are applied to the TEA2260/61 through a small pulse-transformer to the IN input (Pin 2). This input is sensitive to positive square pulses. The typical threshold of this input is 0.85V. The frequency of pulses coming from the secondary regulator can be lower or higher than the frequency of the starting oscillator. The TEA2260/61has no soft-starting system when it receives pulses from the secondary. The softstarting has to be located in the secondary regulator. Due to the principle of the primary regulation, pulses generated by the starting system automatically disappear when the voltage delivered by the SMPS increases. Stand-by Mode - Normal Mode Transition During the transition there are simultaneously pulses coming from the primary and secondary regulators. These signals are not synchronized and some care has to betaken toensure the safety of the switching power transistor. A very sure and simple way consist in checking the transformer demagnetization state. - A primary pulse is taken in account only if the transformer is demagnetized after a conduction of the power transistor required by the secondary regulator. - A secondary pulse is taken in account only if the transformer is demagnetized after a conduction of the power transistor required by the primary regulator. With this arrangement the switching safety area of the power transistor is respected and there is no risk of transformer magnetization. The magnetization state of the transformer is checked by sensing the voltage across a winding of the transformer (generally the same which supplies the TEA2261). This is made by connecting a resistor between this winding and the demagnetization sensing input of the circuit (Pin 1).
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TEA2260 - TEA2261
SECURITY FUNCTIONS OF THE TEA2260 (see flow-chart below) - Undervoltage detection. This protection works in association with the starting device "VCC switch" (see paragraph Starting-mode - standby mode). If VCC is lower than VCCstop (typically 7.4V) output pulses are inhibited, in order to avoid wrong operation of the power supply or bad power transistor drive. - Overvoltage detection. If VCC exceeds VCCmax (typically 15.7V) output pulses are inhibited. Restarting of the power supply is obtained by reducing VCC below VCCstop. - Current limitation of the power transistor. The current is measured by a shunt resistor. A double threshold system is used : - When the first threshold (VIM1) is reached, the conduction of the power transistor is stopped until the end of the period : a new conduction signal is needed to obtain conduction again. - Furthermore as long as the first threshold is reached (it means during several periods), an external capacitor C2 is charged. When the voltage across the capacitor reaches VC2 (typiSECURITY FLOW-CHART (TEA2260) cally 2.55V) the output is inhibited. This is called the "repetitive overload protection". If the overload diseappears before VC2 is reached, C2 is discharged, so transient overloads are tolerated. - Second current limitation threshold (VIM2). When this threshold is reached the output of the circuit is immediatly inhibited. This protection is helpfull in case of hard overload for example to avoid the magnetization of the transformer. - Restart of the power supply. After stopping due to VC2, VIM2, VCCMax or VCCstop triggering, restart of the power supply can be obtained by the normal operating of the "V CC switch" but thanks to an integrted counter, if normal restart cannot be obtained after three trials, the circuit is definitively stopped. In this case it is necessary to reduce VCC below approximately 5V to reset the circuit. From a practical point of view, it means that the power supply has to be temporarily disconnected from any power source to get the restart.
S.M.P.S. starting
First threshold reached VIM1 N
Y
Y
Second threshold reached VIM2 N Pulse by pulse current limiting C 2 charged
V < 2.6V C2 VCCmax reached N Normal operating C 2 discharged Restart number = 3 Y Y
Y
N S.M.P.S. stopping V stop reached CC N =N + 1
N
Y
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2261-06.EPS
Reset C 2 discharged
N
Definitive stopping
TEA2260 - TEA2261
SECURITY FUNCTIONS OF THE TEA2261 (see flow-chart below) - Undervoltage detection. This protection works in association with the starting device "VCC switch" (see paragraph Starting-mode - standby mode). If VCC is lower than VCCstop (typically 7.4V) output pulses are inhibited, in order to avoid wrong operation of the power supply or bad power transistor drive. - Overvoltage detection. If VCC exceeds VCCmax (typically 15.7V) output pulses are inhibited and the external capacitor C 2 is charged as long as VCC is higher than VCC stop. Restarting of the power supply is obtained by reducing VCC below VCCstop except if the voltage across C2 reaches VC2 (typically 2.55V) (refer to "Restart of the power supply" paragraph).In this last case, the circuit is definitively stopped. - Current limitation of the power transistor. The current is measured by a shunt resistor. A double threshold system is used : - When the first threshold (VIM1) is reached, the conduction of the power transistor is stopped until the end of the period : a new conduction signal is needed to obtain conduction again. - Furthermore as long as the first threshold is reached (it means during several periods), an SECURITY FLOW-CHART (TEA2261) external capacitor C2 is charged. When the voltage across the capacitor reaches VC2 (typically 2.55V) the output is inhibited. This is called the "repetitive overload protection". If the overload diseappears before VC2 is reached, C2 is discharged, so transient overloads are tolerated. - Second current limitation threshold (VIM2). When this threshold is reached the output of the circuit is immediatly inhibited. This protection is helpfull in case of hard overload for example to avoid the magnetization of the transformer. - Restart of the power supply. After stopping due to VIM2, VCCMax or VCCstop triggering, restart of the power supply can be obtained by the normal operating of the "VCC switch" VCC switch sequency from VCCstop to VCCstart . After stopping due to VC2 threshold reaching, the circuit is definitively stopped. In this case it is necessary to reduce VCC below approximately 5V to reset the circuit. From a practical point of view, it means that the power supply has to be temporarily disconnected from any power source to get the restart.
S.M.P.S. starting
First threshold reached VIM1 N
Y
Second threshold reached VIM2 Y Y C2 charged S.M.P.S. stopped
N
V CCmax reached N Normal operating C 2 discharged
Pulse by pulse current limiting C2 charged
VC2 < 2.6V VC2 < 2.6V Y N
Y
N Definitive stopping
Y
7/9
2261-07.EPS
Reset C2 discharged
N
TEA2260 - TEA2261
TYPICAL APPLICATION (Master/slavearchitecture)
170 VAC 270 VAC
4 x 1N4007 22k 3W 39 2.2 /0.5W 2.2µF 16V 10 1W 330µ F 25V BA157 1N4148
3
13 PLR811
BY218-600 P1
135V 0.8A
150µ F 385V 4.7k 1k 3.3 nF
20
6 P2 1nF 9
19 14 BY218-100
12V 0.5A 470µ F 25V
47k 100µ F 250V 2.2k 7.5V 1A 120k
22k
1k
7
17 22
1000µ F 25V BC547C 25V 1A 1000µ F 25V
10k Stand-by cont rol
7
6
4
5
12
13
16
15
BY218-100 21
1.2nF
75 k
TEA2260/61
11 10 2 9 8 3 14 1nF 82k 330 1nF nF 330 nF 1 2.2µH
22k 2 4 6 5
47µF
BY299
SGSF 344
10µF 16V 220 16W
TEA5170
3 7 8 1 47nF
BZX85-3V0
100
330 0.135 / 1W
18
2.7nF 1kV
560 pF 2% 1N4148
150pF Sync . input 6.8k
100pF Small signal secondary ground Power primary ground Secondary ground (isolated from mains) POUT : 140W f : 32kHz
1k
270 100k 1%
TV - SET SMPS (with TEA5170) Input voltage range 170VAC 270VAC Input DC voltage range 210VDC 370VDC Output power in normal mode 25W < PO < 140W Output power in stand by mode 2W < PO < 45W Operating frequency 32 kHz Efficiency at full load > 80% Efficiency in stand by mode > 50% Short circuit protected Open load protected Long duration overload protected Complete shutdown after repetitive default detection Load regulation (VDC = 310V) Output 135V (± 0.18%) Output 25V (± 2%) Line regulation Output 135V (± 0.13%) Output 25V (± 0.17%) (210V < VDC < 370V) (I135 : 0.8A ; I25 : 1A) (I135 : 0.01A to 0.8A ; I25 = 1A) (I135 : 0.8A ; I25 : 0.5A > 1A)
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2261-08.EPS
TEA2260 - TEA2261
PACKAGE MECHANICAL DATA 16 PINS - PLASTIC DIP
a1
I
b Z
B e3
e
L
b1
E
D
16
9
F
1
8
Dimensions a1 B b b1 D E e e3 F i L Z
Min. 0.51 0.77
Millimeters Typ.
Max. 1.65
Min. 0.020 0.030
Inches Typ.
Max. 0.065
0.5 0.25 20 8.5 2.54 17.78 7.1 5.1 3.3 1.27
0.020 0.010 0.787 0.335 0.100 0.700 0.280 0.201 0.130 0.050
DIP16.TBL
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No licence is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without noti ce. This publication supersedes and replaces all information previously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics. © 1994 SGS-THOMSON Microelectronics - All Rights Reserved Purchase of I2C Components of SGS-THOMSON Microelectronics, conveys a license under the Philips I2C Patent. Rights to use these components in a I2C system, is granted provided that the system confo rms to the I2C Standard Specifications as defined by Philips. SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A.
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PM-DIP16.EPS