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Da ta sheet, V2.0, 1 F eb 2002
PWM-FF IC
ICE2AS01/S01G ICE2BS01/S01G
Off-Line SMPS Current Mode Controller
P o w e r M a n a g em e n t & S u p p l y
N e v e r
s t o p
t h i n k i n g .
ICE2AS01/G ICE2BS01/G Revision History: Previous Version: Page Subjects (major changes since last revision) 2002-02-01 Datasheet
For questions on technology, delivery and prices please contact the Infineon Technologies Offices in Germany or the Infineon Technologies Companies and Representatives worldwide: see our webpage at http:// www.infineon.com CoolMOSTM, CoolSETTM are trademarks of Infineon Technologies AG.
Edition 2002-02-01 Published by Infineon Technologies AG, St.-Martin-Strasse 53, D-81541 München
© Infineon Technologies AG 1999.
All Rights Reserved. Attention please! The information herein is given to describe certain components and shall not be considered as warranted characteristics. Terms of delivery and rights to technical change reserved. We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding circuits, descriptions and charts stated herein. Infineon Technologies is an approved CECC manufacturer. Information For further information on technology, delivery terms and conditions and prices please contact your nearest Infineon Technologies Office in Germany or our Infineon Technologies Representatives worldwide (see address list). Warnings Due to technical requirements components may contain dangerous substances. For information on the types in question please contact your nearest Infineon Technologies Office. Infineon Technologies Components may only be used in life-support devices or systems with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system, or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered.
ICE2AS01/G ICE2BS01/G
Off-Line SMPS Current Mode Controller
Product Highlights
P-DIP-8-4
· Enhanced Protection Functions all with Auto Restart · Lowest Standby Power Dissipation · Very Accurate Current Limiting
P-DSO-8-3
Features
· · · · · · · · · · · · · Only few external Components required Input Undervoltage Lockout 67kHz/100kHz fixed Switching Frequency Max Duty Cycle 72% Low Power Standby Mode to support "Blue Angle" Norm Latched Thermal Shut Down Overload and Open Loop Protection Overvoltage Protection during Auto Restart Adjustable Peak Current Limitation via External Resistor Overall Tolerance of Current Limiting < ±5% Internal Leading Edge Blanking Soft Start Soft Switching for Low EMI
Description
This stand alone controller provides several special enhancements to satisfy the needs for low power standby and protection features. In standby mode frequency reduction is used to lower the power consumption and provide a stable output voltage in this mode. The frequency reduction is limited to 20kHz / 21.5 kHz (typ.) to avoid audible noise. In case of failure modes like open loop, overvoltage or overload due to short circuit the device switches in Auto Restart Mode which is controlled by the internal protection unit. By means of the internal precise peak current limitation the dimension of the transformer and the secondary diode can be lower which leads to more cost efficiency.
Typical Application
+
85 ... 270 VAC
RStart-up
Snubber
Converter DC Output
-
CVCC
VCC
Feedback
Low Power StandBy
Power Management
SoftS
Soft-Start Control
Gate
PWM Controller Current Mode
Precise Low Tolerance Peak Current Limitation
CSoft Start
Isense
FB
Protection Unit
RSense
GND
Feedback
ICE2AS01 / ICE2BS01
Type ICE2AS01 ICE2AS01G ICE2BS01 ICE2BS01G
Ordering Code Q67040-S4472 Q67040-S4473 Q67040-S4475 Q67040-S4476
Frequency 100kHz 100kHz 67kHz 67kHz
Package P-DIP-8-4 P-DSO-8-3 P-DIP-8-4 P-DSO-8-3
Version 2.0
3
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Table of Contents 1 1.1 1.2 2 3 4 4.1 4.2 4.2.1 4.2.2 4.3 4.4 4.4.1 4.4.2 4.5 4.5.1 4.5.2 4.6 4.7 4.8 4.8.1 4.8.2 4.8.3 5 5.1 5.2 5.3 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 6 7 Page
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 Pin Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 Pin Configuration and Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 Representative Blockdiagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Improved Current Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 PWM-OP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 PWM-Comparator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 Soft-Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 Oscillator and Frequency Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Frequency Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Current Limiting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Leading Edge Blanking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Propagation Delay Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 PWM-Latch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 Protection Unit (Auto Restart Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 Overload & Open loop with normal load . . . . . . . . . . . . . . . . . . . . . . . . .12 Overvoltage due to open loop with no load . . . . . . . . . . . . . . . . . . . . . . .13 Thermal Shut Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 Supply Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 Internal Voltage Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 Control Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 Protection Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 Current Limiting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 Driver Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 Typical Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . .19 Outline Dimension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Version 2.0
4
1 Feb 2002
ICE2AS01/G ICE2BS01/G
1
1.1
Pin Configuration and Functionality
Pin Configuration 1.2 Pin Functionality
Pin 1 2 3 4 5 6 7 8
Symbol N.C. SoftS FB Isense Gate VCC GND N.C.
Function Not connected Soft Start & Auto Restart Control Regulation Fedback Controller Current Sense Input Driver Output Controller Supply Voltage Controller Ground Not connected
SoftS (Soft Start & Auto Restart Control) This pin combines the function of Soft Start in case of Start Up and Auto Restart Mode and the controlling of the Auto Restart Mode in case of an error detection. FB (Feedback) The information about the regulation is provided by the FB Pin to the internal Protection Unit and to the internal PWM-Comparator to control the duty cycle. Isense (Current Sense) The Current Sense pin senses the voltage developed on the series resistor inserted in the source of the external Power Switch. When Isense reaches the internal threshold of the Current Limit Comparator, the Driver output is disabled. By this mean the Over Current Detection is realized. Furthermore the current information is provided for the PWM-Comparator to realize the Current Mode. Gate (Driver Output) The current and slew rate capability of this pin are suited to drive Power MOSFETs. VCC (Power supply) This pin is the positiv supply of the IC. The operating range is between 8.5V and 21V. To provide overvoltage protection the driver gets disabled when the voltage becomes higher than 16.5V during Start up Phase. GND (Ground) This pin is the ground of the primary side of the SMPS.
Package P-DIP-8-4 G-Package P-DSO-8-3
N.C.
1
8
N.C.
SoftS
2
7
GND
FB
3
6
VCC
Isense
4
5
Gate
Figure 1
Pin Configuration (top view)
Version 2.0
5
1 Feb 2002
2
Figure 2
CLine Snubber + Converter DC Output VOUT CVCC
Power Management Undervoltage Lockout
13.5V 8.5V
Version 2.0
Internal Bias
0.72
85 ... 270 VAC
RStart-up
VCC
C1 Power-Down Reset Oscillator
Duty Cycle max
16.5V
6.5V
4.0V
Voltage Reference
Clock
C2
G1
RSoft-Start
Soft Start Soft-Start Comparator
Power-Up Reset
6.5V 5.3V 4.8V 4.0V
SoftS
PWM-Latch
S Q
5.6V
G3 G4
R Q S Q
CSoft-Start
R Q
C4
Representative Blockdiagram
6
G2 Gate Driver
Error-Latch PWM Comparator
5.3V
T1
6.5V
Spike Blanking 5µs
4.8V
RFB
C3
Gate
0.3V C5
fosc
Vcsth
Leading Edge Blanking 200ns Current-Limit Comparator
FB
fnorm fstandby UFB
x3.65 PWM OP Improved Current Mode Current Limiting
0.8V
10k
RSense
Thermal Shutdown
Tj >140°C
Isense
D1
Protection Unit
Standby Unit
Propagation-Delay Compensation
ICE2AS01 / ICE2BS01
Optocoupler
GND
ICE2BS01/SO1G
ICE2AS01/SO1G
Frequency in Normal Mode fnorm:
67kHz
100kHz 21.5kHz
Frequency in Standby Mode fstandby: 20kHz
ICE2AS01/G ICE2BS01/G
Representative Blockdiagram
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
3
3.1
Functional Description
Power Management
M ain L in e (1 00 V -3 80 V )
3.2
Improved Current Mode
S o ft-S ta rt C o m p a ra to r P W M -L a tch
R Q
R S tart-U p
P rim ary W in ding
C VC C
VCC
FB
D rive r
Pow er M anagem ent U n de rvolta g e L o ckou t 1 3 .5V 8 .5 V P o w er-D ow n R e set V o lta g e R efe ren ce P o w er-U p R e se t 6.5 V 5.3 V 4.8 V 4.0 V In te rn a l B ias
P W M C o m p a ra to r
S 0 .8V Q
PW M OP x3 .6 5 Im proved C urrent M ode Ise n se
R
Q P W M -L atch
6 .5 V S S o ftS Q
Figure 4
E rro r-L a tch S o ft-S ta rt C om p ara tor
Current Mode
R Soft-Sta rt
Current Mode means that the duty cycle is controlled by the slope of the primary current. This is done by comparison the FB signal with the amplified current sense signal.
C S oft-Start
T1
E rror-D ete ctio n
A m p lified C u rren t S ig n al
Figure 3 Power Management
The Undervoltage Lockout monitors the external supply voltage VVCC. In case the IC is inactive the current consumption is max. 55µA. When the SMPS is plugged to the main line the current through RStart-up charges the external Capacitor CVCC. When VVCC exceeds the on-threshold VCCon=13.5V the internal bias circuit and the voltage reference are switched on. After it the internal bandgap generates a reference voltage VREF=6.5V to supply the internal circuits. To avoid uncontrolled ringing at switch-on a hysteresis is implemented which means that switch-off is only after active mode when Vcc falls below 8.5V. In case of switch-on a Power Up Reset is done by reseting the internal error-latch in the protection unit. When VVCC falls below the off-threshold VCCoff=8.5V the internal reference is switched off and the Power Down reset let T1 discharging the soft-start capacitor CSoft-Start at pin SoftS. Thus it is ensured that at every switch-on the voltage ramp at pin SoftS starts at zero.
FB
0 .8 V D rive r
t
T on
t
Figure 5 Pulse Width Modulation In case the amplified current sense signal exceeds the FB signal the on-time Ton of the driver is finished by reseting the PWM-Latch (see Figure 5).
Version 2.0
7
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
The primary current is sensed by the series resistor RSense inserted in the source of the external Power Switch. By means of Current Mode the regulation of the secondary voltage is insensitive on line variations. Line variation causes varition of the increasing current slope which controls the duty cycle. The external RSense allows an individual adjustment of the maximum source current of the external Power Switch.
V OSC
m a x. D u ty C yc le
V olta ge R a m p
S oft-S tart C o m p ara to r
P W M C o m pa ra to r
t
FB P W M -La tch
O s cilla to r
0 .8 V FB 0 .3 V
0.3V C5 G a te D rive r
0.8V 1 0 k x3 .6 5
G a te D rive r
t
V O SC
T2 C1 V oltage Ram p
Figure 6
R1
2 0p F
t
Figure 7 Light Load Conditions
V1
PW M OP
3.2.1
PWM-OP
Improved Current Mode
To improve the Current Mode during light load conditions the amplified current ramp of the PWM-OP is superimposed on a voltage ramp, which is built by the switch T2, the voltage source V1 and the 1st order low pass filter composed of R1 and C1 (see Figure 6, Figure 7). Every time the oscillator shuts down for max. duty cycle limitation the switch T2 is closed by VOSC. When the oscillator triggers the Gate Driver T2 is opened so that the voltage ramp can start (see Figure 7). In case of light load the amplified current ramp is to small to ensure a stable regulation. In that case the Voltage Ramp is a well defined signal for the comparison with the FB-signal. The duty cycle is then controlled by the slope of the Voltage Ramp. By means of the C5 Comparator the Gate Driver is switched-off until the voltage ramp exceeds 0.3V. It allows the duty cycle to be reduced continously till 0% by decreasing VFB below that threshold.
The input of the PWM-OP is applied over the internal leading edge blanking to the external sense resistor RSense connected to pin ISense. RSense converts the source current into a sense voltage. The sense voltage is amplified with a gain of 3.65 by PWM OP. The output of the PWM-OP is connected to the voltage source V1. The voltage ramp with the superimposed amplified current singal is fed into the positive inputs of the PWMComparator, C5 and the Soft-Start-Comparator.
3.2.2
PWM-Comparator
The PWM-Comparator compares the sensed current signal of the external Power Switch with the feedback signal VFB (see Figure 8). VFB is created by an external optocoupler or external transistor in combination with the internal pullup resistor RFB and provides the load information of the feedback circuitry. When the amplified current signal of the external Power Switch exceeds the signal VFB the PWM-Comparator switches off the Gate Driver.
Version 2.0
8
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
pullup resistor RSoft-Start. The Soft-Start-Comparator compares the voltage at pin SoftS at the negative input with the ramp signal of the PWM-OP at the positive input. When Soft-Start voltage VSoftS is less than Feedback voltage VFB the Soft-Start-Comparator limits the pulse width by reseting the PWM-Latch (see Figure 9). In addition to Start-Up, Soft-Start is also activated at each restart attempt during Auto Restart. By means of the above mentioned CSoft-Start the Soft-Start can be defined by the user. The Soft-Start is finished when VSoftS exceeds 5.3V. At that time the Protection Unit is activated by Comparator C4 and senses the FB by Comparator C3 wether the voltage is below 4.8V which means that the voltage on the secondary side of the SMPS is settled. The internal Zener Diode at SoftS with breaktrough voltage of 5.6V is to prevent the internal circuit from saturation (see Figure 10).
6 .5 V 5 .6 V
6 .5 V R FB FB S o ft-S ta rt C o m p ara to r P W M -L atch
P W M C o m p a rato r
0 .8 V
O p to co u p le r
PW M OP Ise n se x3 .65 Im proved Current M ode
P o w e r-U p R e s e t E rro r-L a tc h
R Q
R S o ft-S ta rt S o ftS 6 .5 V 5 .3 V C4 G2
S
Q
Figure 8
PWM Controlling
3.3
Soft-Start
FB
4 .8 V R FB
C3 C lo c k
R
Q
G a te D riv e r
S Q
V S oftS
5 .6 V 5 .3 V
P W M -L a tc h
Figure 10
Activation of Protection Unit
T S oft-S tart
The Start-Up time TStart-Up within the converter output voltage VOUT is settled must be shorter than the SoftStart Phase TSoft-Start (see Figure 11).
G a te D rive r
t
C Soft - Start =
T Soft - Start R Soft - Start × 1, 69
By means of Soft-Start there is an effective minimization of current and voltage stresses on the external Power Switch, the clamp circuit and the output overshoot and prevents saturation of the transformer during Start-Up.
t
Figure 9 Soft-Start Phase
The Soft-Start is realized by the internal pullup resistor RSoft-Start and the external Capacitor CSoft-Start (see Figure 2). The Soft-Start voltage VSoftS is generated by charging the external capacitor CSoft-Start by the internal
Version 2.0
9
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
V S o ftS
5 .3 V
f OSC
kHz
fnorm
T S oft-S ta rt V FB 4 .8 V
ICE2BS01 fnorm: 67kHz 20kHz fstandby:
t
fstandby 1,0 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8 1,9 2
V
VFB
ICE2AS01 100kHz 21.5kHz
V OUT
V O UT
T S ta rt-U p
t
Figure 12
Frequency Dependence
3.5
Current Limiting
t
Figure 11 Start Up Phase
3.4
Oscillator and Frequency Reduction Oscillator
3.4.1
The oscillator generates a frequency fswitch = 100kHz. A resistor, a capacitor and a current source and current sink which determine the frequency are integrated. The charging and discharging current of the implemented oscillator capacitor are internally trimmed, in order to achieve a very accurate switching frequency. The ratio of controlled charge to discharge current is adjusted to reach a max. duty cycle limitation of Dmax=0.72.
There is a cycle by cycle current limiting realised by the Current-Limit Comparator to provide an overcurrent detection. The source current of the external Power Switch is sensed via an external sense resistor RSense . By means of RSense the source current is transformed to a sense voltage VSense. When the voltage VSense exceeds the internal threshold voltage Vcsth the Current-Limit-Comparator immediately turns off the gate drive. To prevent the Current Limiting from distortions caused by leading edge spikes a Leading Edge Blanking is integrated at the Current Sense. Furthermore a Propagation Delay Compensation is added to support the immedeate shut down of the Power Switch in case of overcurrent.
3.5.1
Leading Edge Blanking
V S en s e
V c s th t L E B = 22 0 ns
3.4.2
Frequency Reduction
The frequency of the oscillator is depending on the voltage at pin FB. The dependence is shown in Figure 12. This feature allows a power supply to operate at lower frequency at light loads thus lowering the switching losses while maintaining good cross regulation performance and low output ripple. In case of low power the power consumption of the whole SMPS can now be reduced very effective. The minimal reachable frequency is limited to 20kHz / 21.5 kHz to avoid audible noise in any case.
t
Figure 13 Leading Edge Blanking Each time when the external Power Switch is switched on a leading spike is generated due to the primary-side capacitances and secondary-side rectifier reverse
Version 2.0
10
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
recovery time. To avoid a premature termination of the switching pulse this spike is blanked out with a time constant of tLEB = 220ns. During that time the output of the Current-Limit Comparator cannot switch off the gate drive.
VOSC
max. Duty Cycle
3.5.2
Propagation Delay Compensation
VSense
off time
In case of overcurrent detection the shut down of the external Power Switch is delayed due to the propagation delay of the circuit. This delay causes an overshoot of the peak current Ipeak which depends on the ratio of dI/dt of the peak current (see Figure 14). .
Propagation Delay
t
Vcsth
S ig n a l2
I S e ns e
I p ea k 2 I p ea k 1 I L im it I O v ers h oo t2
S ig n a l1 t P ro pa ga tion D e la y
Signal1
Figure 15
Signal2
t
I O v e rs ho ot1
Dynamic Voltage Threshold Vcsth
with compensation
without compensation
V
t
Figure 14 Current Limiting The overshoot of Signal2 is bigger than of Signal1 due to the steeper rising waveform. A propagation delay compensation is integrated to bound the overshoot dependent on dI/dt of the rising primary current. That means the propagation delay time between exceeding the current sense threshold Vcsth and the switch off of the external Power Switch is compensated over temperature within a range of at least .
1,3 1,25 1,2
VSense
1,15 1,1 1,05 1 0,95 0,9 0 0,2 0,4 0,6 0,8 1 1,2 1,4 1,6 1,8 2
dVSense dt
V µs
Figure 16
Overcurrent Shutdown
0 RSense
dI × peak dt
1
dVSense dt
3.6
PWM-Latch
So current limiting is now capable in a very accurate way (see Figure 16). E.g. Ipeak = 0.5A with RSense = 2 . Without propagation delay compensation the current sense threshold is set to a static voltage level Vcsth=1V. A current ramp of dI/dt = 0.4A/µs, that means dVSense/dt = 0.8V/µs, and a propagation delay time of i.e. tPropagation Delay =180ns leads then to an Ipeak overshoot of 12%. By means of propagation delay compensation the overshoot is only about 2% (see Figure 15). The propagation delay compensation is done by means of a dynamic threshold voltage Vcsth (see Figure 15). In case of a steeper slope the switch off of the driver is earlier to compensate the delay.
The oscillator clock output applies a set pulse to the PWM-Latch when initiating the external Power Switch conduction. After setting the PWM-Latch can be reset by the PWM-OP, the Soft-Start-Comparator, the Current-Limit-Comparator, Comparator C3 or the Error-Latch of the Protection Unit. In case of reseting the driver is shut down immediately.
3.7
Driver
The driver is a fast totem pole gate drive, which is designed to avoid cross conduction currents and which is equipped with a Zener diode Z1 (see Figure 17) in order to improve the control of the gate attached power
Version 2.0
11
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
transistors as well as to protect them against undesirable gate overvoltages. failure modes are latched by an Error-Latch. Additional thermal shutdown is latched by the Error-Latch. In case of those failure modes the Error-Latch is set after a blanking time of 5µs and the external Power Switch is shut down. That blanking prevents the Error-Latch from distortions caused by spikes during operation mode.
VCC
P W M -La tch
1
G a te
3.8.1
Overload & Open loop with normal load
Z1
O verload & O pen loop/norm al load
FB 4 .8 V
F ailure D e tectio n
5µ s B la nking
Figure 17
Gate Driver
t S oftS 5 .3 V
S oft-S tart P h ase
At voltages below the undervoltage lockout threshold VVCCoff the gate drive is active low. The driver-stage is optimized to minimize EMI and to provide high circuit efficiency. This is done by reducing the switch on slope when reaching the external Power Switch threshold. This is achieved by a slope control of the rising edge at the driver's output (see Figure 18).
D river
T B u rs t1
t
T R e s tart
V G a te
ca . t = 1 3 0 n s
C L o ad = 1n F
VC C
t
5V
1 3 .5 V 8 .5V
t
Figure 18 Gate Rising Slope
t
Thus the leading switch on spike is minimized. When the external Power Switch is switched off, the falling shape of the driver is slowed down when reaching 2V to prevent an overshoot below ground. Furthermore the driver circuit is designed to eliminate cross conduction of the output stage.
Figure 19
Auto Restart Mode
Figure 19 shows the Auto Restart Mode in case of overload or open loop with normal load. The detection of open loop or overload is provided by the Comparator C3, C4 and the AND-gate G2 (see Figure20).
3.8
Protection Unit (Auto Restart Mode)
An overload, open loop and overvoltage detection is integrated within the Protection Unit. These three
Version 2.0
12
1 Feb 2002
ICE2AS01/G ICE2BS01/G
Functional Description
3.8.2
6.5 V
P o w e r U p R e se t S o ftS
Overvoltage due to open loop with no load
R S oft-S tart
FB
O pen loop & no load conditio n
5 µs B la n kin g
C S oft-S tart 5 .3 V
T1
4 .8V
C4
G2
E rro r-L a tch
F ailure D ete ction
4 .8V C3
FB
R FB
S o ftS 5 .3V
4 .0V O v erv olta g e D e te ction P ha se
S o ft-S ta rt P ha se
t
6 .5 V
Figure 20
FB-Detection
D rive r
T B urs t2 T R es ta rt t
The detection is activated by C4 when the voltage at pin SoftS exceeds 5.3V. Till this time the IC operates in the Soft-Start Phase. After this phase the comparator C3 can set the Error-Latch in case of open loop or overload which leads the feedback voltage VFB to exceed the threshold of 4.8V. After latching VCC decreases till 8.5V and inactivates the IC. At this time the external Soft-Start capacitor is discharged by the internal transistor T1 due to Power Down Reset. When the IC is inactive VCC increases till VCCon = 13.5V by charging the Capacitor CVCC by means of the Start-Up Resistor RStart-Up. Then the Error-Latch is reset by Power Up Reset and the external Soft-Start capacitor CSoft-Start is charged by the internal pullup resistor RSoftStart . During the Soft-Start Phase which ends when the voltage at pin SoftS exceeds 5.3V the detection of overload and open loop by C3 and G2 is inactive. In this way the Start Up Phase is not detected as an overload. But the Soft-Start Phase must be finished within the Start Up Phase to force the voltage at pin FB below the failure detection threshold of 4.8V.
O ve rvo ltag e D ete ctio n
t
VCC 1 6.5 V 1 3.5 V 8.5 V
t
Figure 21
Auto Restart Mode
Figure 21 shows the Auto Restart Mode for open loop and no load condition. In case of this failure mode the converter output voltage increases and also VCC. An additional protection by the comparators C1, C2 and the AND-gate G1 is implemented to consider this failure mode (see Figure 22).
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Functional Description
VCC
6 .5 V
1 6 .5 V
C1
E rro r L a tch G1
R S o ft-S ta rt
4 .0 V S o ftS C2
C S o ft-S ta rt
T1
P o w e r U p R e se t
Figure 22
Overvoltage Detection
The overvoltage detection is provided by Comparator C1 only in the first time during the Auto Restart Mode till the Soft-Start voltage exceeds the threshold of the Comparator C2 at 4.0V and the voltage at pin FB is above 4.8V. When VCC exceeds 16.5V during the overvoltage detection phase C1 can set the Error-Latch and the Burst Phase during Auto Restart Mode is finished earlier. In that case TBurst2 is shorter than TSoftStart . By means of C2 the normal operation mode is prevented from overvoltage detection due to varying of VCC concerning the regulation of the converter output. When the voltage VSoftS is above 4.0V the overvoltage detection by C1 is deactivated.
3.8.3
Thermal Shut Down
Thermal Shut Down is latched by the Error-Latch when junction temperature Tj of the pwm controller is exceeding an internal threshold of 140°C. In that case the IC switches in Auto Restart Mode.
Note:
All the values which are mentioned in the functional description are typical. Please refer to Electrical Characteristics for min/max limit values.
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Electrical Characteristics
4
4.1
Note:
Electrical Characteristics
Absolute Maximum Ratings
Absolute maximum ratings are defined as ratings, which when being exceeded may lead to destruction of the integrated circuit. For the same reason make sure, that any capacitor that will be connected to pin 6 (VCC) is discharged before assembling the application circuit.
Parameter
Symbol
Limit Values min. max. 22 6.5 6.5 3 150 150 90 185 2
Unit
Remarks
VCC Supply Voltage FB Voltage SoftS Voltage ISense Junction Temperature Storage Temperature Thermal Resistance Junction-Ambient Thermal Resistance Junction-Ambient ESD Capability1)
1)
VCC VFB VSoftS ISense Tj TS RthJA RthJA VESD
-0.3 -0.3 -0.3 -0.3 -40 -50 -
V V V V °C °C K/W K/W kV P-DIP-8-4 P-DSO-8-3 Human Body Model Controller & CoolMOS
Equivalent to discharging a 100pF capacitor through a 1.5 k series resistor
4.2
Note:
Operating Range
Within the operating range the IC operates as described in the functional description.
Parameter
Symbol
Limit Values min. max. 21 130
Unit
Remarks
VCC Supply Voltage Junction Temperature of Controller
VCC TJCon
VCCoff -25
V °C limited due to thermal shut down of controller
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Electrical Characteristics
4.3
Note:
Characteristics
The electrical characteristics involve the spread of values guaranteed within the specified supply voltage and junction temperature range TJ from 25 °C to 125 °C.Typical values represent the median values, which are related to 25°C. If not otherwise stated, a supply voltage of VCC = 15 V is assumed.
4.3.1
Supply Section
Parameter
Symbol min.
Limit Values typ. 27 5.3 6.5 max. 55 7 8
Unit
Test Condition
Start Up Current Supply Current with Inactiv Gate Supply Current with Activ Gate ICE2AS01/G Supply Current with Activ Gate ICE2BS01/G VCC Turn-On Threshold VCC Turn-Off Threshold VCC Turn-On/Off Hysteresis
IVCC1 IVCC2 IVCC3
-
µA mA mA
VCC=VCCon -0.1V VSoftS = 0 IFB = 0 VSoftS = 5V IFB = 0 CGate = 1nF VSoftS = 5V IFB = 0 CGate = 1nF
IVCC3
-
6
7.5
mA
VCCon VCCoff VCCHY
13 4.5
13.5 8.5 5
14 5.5
V V V
4.3.2
Internal Voltage Reference
Parameter
Symbol min.
Limit Values typ. 6.50 max. 6.63
Unit
Test Condition
Trimmed Reference Voltage
VREF
6.37
V
measured at pin FB
4.3.3
Control Section
Parameter
Symbol min.
Limit Values typ. 100 67 21.5 20 max. 107 72 -
Unit
Test Condition
Oscillator Frequency ICE2AS01/G Oscillator Frequency ICE2BS01/G Reduced Osc. Frequency ICE2AS01/G Reduced Osc. Frequency ICE2AS01/G
fOSC1 fOSC3 fOSC2 fOSC4
93 62 -
kHz kHz kHz kHz
VFB = 4V VFB = 4V VFB = 1V VFB = 1V
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Electrical Characteristics
Frequency Ratio fosc1/fosc2 ICE2AS01/G Frequency Ratio fosc3/fosc4 ICE2BS01/G Max Duty Cycle Min Duty Cycle PWM-OP Gain Max. Level of Voltage Ramp Dmax Dmin AV VMax-Ramp 4.5 3.18 0.67 0 3.45 0.3 3.0 42 4.65 3.35 0.72 3.65 0.85 3.7 50 4.9 3.53 0.77 3.85 4.6 4.9 62 V V V k k VFB < 0V
VFB Operating Range Min Level VFBmin VFB Operating Range Max level VFBmax Feedback Resistance Soft-Start Resistance RFB RSoft-Start
4.3.4
Protection Unit
Parameter
Symbol min.
Limit Values typ. 4.8 5.3 4.0 16.5 140 5 max. 4.95 5.46 4.12 17.2 150 -
Unit
Test Condition
Over Load & Open Loop Detection Limit Activation Limit of Overload & Open Loop Detection Deactivation Limit of Overvoltage Detection Overvoltage Detection Limit Latched Thermal Shutdown Spike Blanking
VFB2 VSoftS1 VSoftS2 VVCC1 TjSD tSpike
4.65 5.15 3.88 16 130 -
V V V V °C µs
VSoftS > 5.5V VFB > 5V VFB > 5V VCC > 17.5V VSoftS < 3.8V VFB > 5V guaranteed by design
4.3.5
Current Limiting
Parameter
Symbol min.
Limit Values typ. 1.00 max. 1.05
Unit
Test Condition
Peak Current Limitation (incl. Propagation Delay Time) (see Figure 7) Leading Edge Blanking
Vcsth
0.95
V
dVsense / dt = 0.6V/µs
tLEB
-
220
-
ns
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Electrical Characteristics
4.3.6 Driver Section
Parameter
Symbol min.
Limit Values typ. 0.95 1.0 0.88 1.6 0.2 11.5 10 7.5 160 65 max. 1.2 1.5 2.2 0.7
Unit
Test Condition
GATE Low Voltage
VGATE
-0.2
V V V V V V V V ns ns A A
VVCC = 5 V IGate = 5 mA VVCC = 5 V IGate = 20 mA IGate = 0 A IGate = 50 mA IGate = -50 mA VVCC = 20V CL = 4.7nF VVCC = 11V CL = 4.7nF VVCC = VVCCoff + 0.2V CL = 4.7nF VGate = 2V ...9V1) CL = 4.7nF VGate = 9V ...2V1) CL = 4.7nF CL = 4.7nF2) CL = 4.7nF2)
GATE High Voltage
VGATE
-
GATE Rise Time GATE Fall Time GATE Current, Peak, Rising Edge GATE Current, Peak, Falling Edge
1) 2)
tr tf IGATE IGATE
-0.5 -
Transient reference value Design characteristics (not meant for production testing)
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Typical Performance Characteristics
5
40 38
Typical Performance Characteristics
13,58
VCC Turn-On Threshold V CCon [V]
13,56 13,54 13,52 13,50 13,48 13,46 13,44 13,42 -25 -15
PI-004-190101
Start Up Current I VCC1 [µA]
36 34
PI-001-190101
32 30 28 26 24 22 -25 -15
-5
5
15
25
35
45
55
65
75
85
95
105 115 125
-5
5
15
25
35
45
55
65
75
85
95 105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 23
6,0
Start Up Current IVCC1 vs. Tj
Figure 26
8,67
VCC Turn-On Threshold VVCCon vs. Tj
VCC Turn-Off Threshold V VCCoff [V]
8,64 8,61 8,58
PI-005-190101
Supply Current IVCC2 [mA]
5,7
5,4
PI-003-190101
8,55 8,52 8,49 8,46 8,43 8,40 -25 -15
5,1
4,8
4,5 -25 -15
-5
5
15
25
35
45
55
65
75
85
95 105 115 125
-5
5
15
25
35
45
55
65
75
85
95 105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 24
Supply Current IVCC2 vs. Tj
Figure 27
VCC Turn-On/Off Hysteresis V CCHY [V]
5,10 5,07 5,04 5,01
VCC Turn-Off Threshold VVCCoff vs. Tj
7,0 6,8
ICE2ASO1 ICE2ASO1G
Supply Current I VCC3 [mA]
6,6 6,4 6,2 6,0 5,8 5,6 5,4 5,2 5,0 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
ICE2BSO1 ICE2BSO1G
PI-002-190101
4,95 4,92 4,89 4,86 4,83 -25 -15
-5
5
15
25
35
45
55
65
75
85
95 105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 25
Supply Current IVCC3 vs. Tj
Figure 28
VCC Turn-On/Off HysteresisVVCCHY vs. Tj
Version 2.0
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PI-006-190101
4,98
ICE2AS01/G ICE2BS01/G
Typical Performance Characteristics
6,55
Trimmed Reference Voltage V REF [V]
6,54 6,53 6,52 6,51
PI-007-190101
Reduced Osc. Frequency OSC2 [kHz] f
21,8 21,7 21,6 21,5 21,4 21,3 21,2 21,1 21,0 20,9 20,8 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-009-190101
ICE2ASO1 ICE2ASO1G
6,50 6,49 6,48 6,47 6,46 6,45 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 29
Trimmed Reference VREF vs. Tj
Figure 32
Reduced Osc. Frequency fOSC2 vs. Tj
Oscillator Frequency OSC1 [kHz] f
101,5 101,0 100,5 100,0
PI-008-190101
[kHz]
ICE2ASO1 ICE2ASO1G
102,0
21,0 20,8 20,6 20,4 20,2 20,0 19,8 19,6 19,4 19,2 19,0 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-009a-190101
OSC4
99,5 99,0 98,5 98,0 97,5 97,0 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
Junction Temperature [°C]
Reduced Osc. Frequency f
ICE2BSO1 ICE2BSO1G
Junction Temperature [°C]
Figure 30
Oscillator Frequency fOSC1 vs. Tj
Figure 33
Reduced Osc. Frequency fOSC4 vs. Tj
70,0
4,70 4,68
Oscillator Frequency f OSC3 [kHz]
69,5 69,0 68,5 68,0 67,5
PI-008a-190101
Frequency Ratio fOSC1/fOSC2
4,66 4,64 4,62 4,60 4,58 4,56 4,54 4,52 4,50 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
ICE2ASO1 ICE2ASO1G
PI-010-190101
ICE2BSO1 ICE2BSO1G
67,0 66,5 66,0 65,5 65,0 64,5 64,0 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 31
Oscillator Frequency fOSC3 vs. Tj
Figure 34
Frequency Ratio fOSC1 / fOSC2 vs. Tj
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Typical Performance Characteristics
3,45
4,00
Feedback Resistance R FB [kOhm]
3,43
3,95 3,90 3,85 3,80 3,75 3,70 3,65 3,60 3,55 3,50 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-013-190101
Frequency Ratio fOSC3/fOSC4
3,41 3,39 3,37 3,35 3,33 3,31 3,29 3,27 3,25 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
ICE2BSO1 ICE2BSO1G
PI-010a-190101
Junction Temperature [°C]
Junction Temperature [°C]
Figure 35
0,730 0,728 0,726
Frequency Ratio fOSC3 / fOSC4 vs. Tj
Figure 38
58 56 54 52
Feedback Resistance RFB vs. Tj
Max. Duty Cycle
0,724 0,722 0,720 0,718 0,716 0,714 0,712 0,710 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-011-190101
Soft-Start Resistance R Soft-Start [kOhm]
48 46 44 42 40 -25 -15
-5
5
15
25
35
45
55
65
75
85
95
105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 36
3,70 3,69
Max. Duty Cycle vs. Tj
Figure 39
4,85 4,84
Soft-Start Resistance RSoft-Start vs. Tj
Detection Limit V FB2 [V]
3,68
4,83 4,82 4,81 4,80 4,79 4,78 4,77 4,76
PI-015-190101
PWM-OP Gain AV
3,67 3,66 3,65 3,64 3,63 3,62 3,61 3,60 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-012-190101
4,75 -25 -15
-5
5
15
25
35
45
55
65
75
85
95 105 115 125
Junction Temperature [°C]
Junction Temperature [°C]
Figure 37
PWM-OP Gain AV vs. Tj
Figure 40
Detection Limit VFB2 vs. Tj
Version 2.0
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PI-014-190101
50
ICE2AS01/G ICE2BS01/G
Typical Performance Characteristics
5,35
1,010
Peak Current Limitation V csth [V]
5,34
1,008 1,006 1,004 1,002 1,000 0,998 0,996 0,994 0,992 0,990 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-019-190101
Detection Limit V Soft-Start1 [V]
5,33 5,32 5,31 5,30 5,29 5,28 5,27 5,26 5,25 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-016-190101
Junction Temperature [°C]
Junction Temperature [°C]
Figure 41
4,05
Detection Limit VSoft-Start1 vs. Tj
Figure 44
280
Peak Current Limitation Vcsth vs. Tj
Leading Edge Blanking t LEB [ns]
4,04
270 260 250 240 230 220 210 200 190 180 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-020-190101
Detection Limit V Soft-Start2 [V]
4,03 4,02 4,01 4,00 3,99 3,98 3,97 3,96 3,95 -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125
PI-017-190101
Junction Temperature [°C]
Junction Temperature [°C]
Figure 42
16,80 16,75 16,70 16,65 16,60 16,55 16,50 16,45 16,40 16,35 16,30 16,25 16,20 -25 -15
Detection Limit VSoft-Start2 vs. Tj
Figure 45
Leading Edge Blanking VVCC1 vs. Tj
Overvoltage Detection Limit V VCC1 [V]
-5
5
15
25
35
45
55
65
75
85
95 105 115 125
Junction Temperature [°C]
Figure 43
Overvoltage Detection Limit VVCC1 vs. Tj
Version 2.0
PI-018-190101
22
1 Feb 2002
Preliminary Specification 6 Outline Dimension
ICE2AS01/G ICE2BS01/G
Outline Dimension
P-DSO-8-3 (Plastic Dual Small Outline)
Figure 46
P-DIP-8-4 (Plastic Dual In-line Package)
Figure 47 Dimensions in mm
Version 2.0 23 1 Feb 2002
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Qualität hat für uns eine umfassende Bedeutung. Wir wollen allen Ihren Ansprüchen in der bestmöglichen Weise gerecht werden. Es geht uns also nicht nur um die Produktqualität unsere Anstrengungen gelten gleichermaßen der Lieferqualität und Logistik, dem Service und Support sowie allen sonstigen Beratungs- und Betreuungsleistungen. Dazu gehört eine bestimmte Geisteshaltung unserer Mitarbeiter. Total Quality im Denken und Handeln gegenüber Kollegen, Lieferanten und Ihnen, unserem Kunden. Unsere Leitlinie ist jede Aufgabe mit ,,Null Fehlern" zu lösen in offener Sichtweise auch über den eigenen Arbeitsplatz hinaus und uns ständig zu verbessern. Unternehmensweit orientieren wir uns dabei auch an ,,top" (Time Optimized Processes), um Ihnen durch größere Schnelligkeit den entscheidenden Wettbewerbsvorsprung zu verschaffen. Geben Sie uns die Chance, hohe Leistung durch umfassende Qualität zu beweisen. Wir werden Sie überzeugen. Quality takes on an allencompassing significance at Semiconductor Group. For us it means living up to each and every one of your demands in the best possible way. So we are not only concerned with product quality. We direct our efforts equally at quality of supply and logistics, service and support, as well as all the other ways in which we advise and attend to you. Part of this is the very special attitude of our staff. Total Quality in thought and deed, towards co-workers, suppliers and you, our customer. Our guideline is "do everything with zero defects", in an open manner that is demonstrated beyond your immediate workplace, and to constantly improve. Throughout the corporation we also think in terms of Time Optimized Processes (top), greater speed on our part to give you that decisive competitive edge. Give us the chance to prove the best of performance through the best of quality you will be convinced.
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