ICE2QS03 Datasheet, PDF (5/19 Pages) Infineon Technologies AG – Quasi-Resonant PWM Controller

Quasi-Resonant PWM Controller
ICE2QS03
Pin Configuration and Functionality
1
Pin Configuration and ^{1.3 Pin Functionality}
Functionality
ZC (Zero Crossing)
At this pin, the voltage from the auxiliary winding after
a time delay circuit is applied. Internally, this pin is
1.1
Pin Configuration with PG-DIP- connected to the zero-crossing detector for switch-on
8-6
determination. Additionally, the output overvoltage
detection is realized by comparing the voltage Vzc with
an internal preset threshold.
Pin Symbol Function
1
ZC Zero Crossing
2
FB Feedback
3
CS Current Sense
4
HV High Voltage Input
5
HV High Voltage Input
6
GATE Gate Drive Output
7
VCC Controller Supply Voltage
8
GND Controller Ground
FB (Feedback)
Normally, an external capacitor is connected to this pin
for a smooth voltage V_FB. Internally, this pin is
connected to the PWM signal generator for switch-off
determination (together with the current sensing
signal), the digital signal processing for the frequency
reduction with decreasing load during normal
operation, and the Active Burst Mode controller for
entering Active Burst Mode operation determination
and burst ratio control during Active Burst Mode
operation. Additionally, the open-loop / over-load
protection is implemented by monitoring the voltage at
this pin.
1.2
Package PG-DIP-8-6
ZC 1
8 GND
CS (Current Sense)
This pin is connected to the shunt resistor for the
primary current sensing, externally, and the PWM
signal generator for switch-off determination (together
with the feedback voltage), internally. Moreover, short-
winding protection is realised by monitoring the voltage
Vcs during on-time of the main power switch.
FB 2
CS 3
HV ₄
7 VCC
GATE (Gate Drive Output)
This output signal drives the external main power
switch, which is a power MOSFET in most case.
6
GATE HV (High Voltage)
The pin HV is connected to the bus voltage, externally,
5
HV
and to the power cell, internally. The current through
this pin pre-charges the VCC capacitor with constant
current once the supply bus voltage is applied.
Figure 1
Pin Configuration PG-DIP-8-6(top view)
VCC (Power supply)
VCC pin is the positive supply of the IC. The operating
range is between V_VCCoff and V_VCCOVP.
GND (Ground)
This is the common ground of the controller.
Version 2.0
5
December 4, 2009