ICE2QS02G Datasheet, PDF (3/17 Pages) Infineon Technologies AG – Quasi-Resonant PWM Controller

Quasi-Resonant PWM Controller
Product Highlights
• Quasi-resonant operation for higher efficiency and better EMI
• Digital frequency reduction for higher average efficiency
• Optimized for applications with auxiliary converter
• Various protection features with Latch Mode and Auto-restart Mode
• Adjustable blanking time for Over Load Protection and adjustable
restart time
• Pb-free lead plating; RoHS compliant
ICE2QS02G
ICE2QS02G
PG-DSO-8
Features
• Quasi-resonant operation
• Load dependent digital frequency reduction
• Built-in digital soft-start
• Cycle-by-cycle peak current limitation with built-in
leading edge blanking time
• VCC undervoltage protection
• Mains undervoltage protection with adjustable
hysteresis
• Foldback Point Correction with digitalized sensing
and control circuits
• Over Load Protection with adjustable blanking time
• Adjustable restart time after Over Load Protection
• Adjustable output overvoltage protection with Latch
mode
• Short-winding protection with Latch mode
• Maximum on time limitation
• Maximum switching period limitation
Description
ICE2QS02G is a second generation quasi-resonant
PWM controller optimized for off-line power supply
applications such as LCD TV, audio and printers, where
an auxiliary power supply for the IC is provided. The
digital frequency reduction with decreasing load enables
a quasi-resonant operation till very low load. As a result,
the system efficiency is significantly improved compared
to a free running quasi resonant converter implemented
with maximum switching frequency limitation only.
In addition, numerous protection functions have been
implemented in the IC to protect the system and
customize the IC for the chosen application. All of these
make the ICE2QS02G an outstanding product for real
quasi-resonant flyback converter in the market.
Mains
Input Voltage
C_bus
R_VINS1
Typical Application
RZC2
Snubber
RZC1
RVINS2
CZC
RBL
Auxiliary Supply
BL
VINS
VCC ZC
CBL
GND
CFB
FB
Vcc Power Management
Zero Crossing Detection
Global Protection Block
Digital Process Block
Current Mode Control
control unit
Gate
Driver
GATE
Current
Limitation
ICE2QS02G
CS
RCS
Wp
DO
W_s
L_f
Cf
VO
C_O
Wa
C_PS
Rb1
CDS
Optocoupler
Rb2
Rovs1
Rc1
TL431
Cc1 Cc2
R_ovs2
Type
ICE2QS02G
Version 2.0
Package
PG-DSO-8-8
3
13 June 2008