ICE3AR1080VJZ Datasheet, PDF (14/43 Pages) Infineon Technologies AG – Of f -Line SMPS Cur rent Mode Cont rol ler wi th integrated 800V

CoolSET™ F3R80
ICE3AR1080VJZ
Functional Description
3.3.1 PWM-OP
The input of the PWM-OP is applied over the internal leading edge blanking to the external sense resistor R_Sense
connected to pin CS. R_Sense converts the source current into a sense voltage. The sense voltage is amplified with a
gain of 3.25 by PWM OP. The output of the PWM-OP is connected to the voltage source V₁. The voltage ramp with
the superimposed amplified current signal is fed into the positive inputs of the PWM-Comparator C8 and the Soft-Start-
Comparator (Figure 9).
3.3.2 PWM-Comparator
The PWM-Comparator compares the sensed current signal of the integrated CoolMOS™ with the feedback
signal VFBB (Figure 9). V_FBB is created by an external optocoupler or external transistor in combination with the
internal pull-up resistor R_FB and provides the load information of the feedback circuitry. When the amplified
current signal of the integrated CoolMOS™ exceeds the signal V_FBB the PWM-Comparator switches off the Gate
Driver.
5V
R_FB
Soft-Start Comparator
FBB
PWM-Latch
C8
PWM Comparator
Optocoupler
0.6V
PWM OP
CS
X3.25
Improved
Current Mode
Figure 9:
PWM Controlling
3.4
Startup Phase
Figure 10: Soft Start
Data Sheet
Soft Start counter
SoftS
Soft Start
Soft Start
Soft-Start
Comparator
C7
&
G7
Gate Driver
0.6V
x3.25
CS
PWM OP
14
V2.0, 2014-01-20