SIP11203 Datasheet, PDF (1/18 Pages) Vishay Siliconix – Synchronous Rectifier Driver with Power Up/Down Control, Output OVP, Error Amplifier and Precision Reference

SiP11203, SiP11204
Vishay Siliconix
Synchronous Rectifier Driver with Power Up/Down Control,
Output OVP, Error Amplifier and Precision Reference
DESCRIPTION
The SiP11203/SiP11204 provide the secondary side
error amplifier, reference voltage and synchronous
rectifier drivers for isolated converter topologies. Both
ICs are capable of being powered via conventional
bias supplies (output inductor winding or power
transformer winding), or from a pulse transformer
supplying the gate timing signals, and both parts
generate a regulated supply for powering the error
amplifier and control circuitry.
During power-up the SiP11203/SiP11204 ensure that
the synchronous rectifiers are held off until the supply
voltages are adequate to guarantee effective
operation of the driver circuits. During the soft-start
interval, a gradual ramp-up of the synchronous
rectifier conduction time is provided. Both ICs also
allow control of the discharge rate of the synchronous
rectifier driver outputs during power-down.
The SiP11203 and SiP11204 are available in a
Pb-free MLP44-16 package and are rated to handle
the industrial ambient temperature range of - 40 to 85 °C.
TYPICAL APPLICATION CIRCUIT
V IN
Half Bridge
PWM
Controlle r
GND
SRH
SRL
Pulse
Transformer
FEATURES
• High Current synchronous rectifier drivers
- 2.2 A source and 4 A sink
• Driver switching synchronized with primary
controller
• Full output control during power-up and power-
down
• 5.5 V to 13 V operating voltage range
• 1.225 V on board bandgap voltage reference
• Can be powered from the pulse transformer
supplying synchronous rectifier timing signals
• On-chip ground-sensing error amplifier
• Programmable rising edge delay
• Output over-voltage protection (OVP)
- SiP11203 turns synchronous rectifiers on
- SiP11204 turns synchronous rectifiers off
• Secondary-side companion chip for the Si9122
Half-Bridge Controller IC
APPLICATIONS
• High efficiency DC-DC Converter Modules and
Bricks
• Telecom and Server Power Supplies
• High Efficiency Intermediate Bus Converters (IBC)
• Half-bridge, full-bridge, or push-pull primary DC-DC
topologies
• Center-tapped or current-doubler secondary
configurations
OUT A
OVPin
OUT B
EA+
Vin _SiP11203 EA-
IN A ^SiP11204 Vref
IN B
EAout
GND
PGND
VL Cpd Rdel Rpd
V OUT
GND
Optoisolator
ZF2
ZF1
Document Number: 73868
www.vishay.com
S11-0975–Rev. C, 16-May-11
1
This document is subject to change without notice.
THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000