SRK2001A Datasheet, PDF (1/20 Pages) STMicroelectronics – Auto-compensation of parasitic inductance

SRK2001A
Adaptive synchronous rectification controller for LLC resonant
converter
Datasheet - production data
Features
 Secondary side synchronous rectification
controller optimized for LLC resonant converter
 Dual gate driver for N-channel MOSFETs
 Adaptive turn-off logic
 Turn-on logic with adaptive masking time
 Auto-compensation of parasitic inductance
 Low consumption mode: 50 µA quiescent
current
 V_CC operating voltage range 4.5 V to 32 V
 High voltage drain-to-source Kelvin sensing for
each SR MOSFET
 Operating frequency up to 500 kHz
 Programmable exit load levels from burst-
mode
 SSOP10 package
Applications
 AC-DC adapters
 All-in-one PC
 High-end flat panel TV
 80+/85+ compliant ATX SMPS
 90+/92+ compliant SERVER SMPS
 Industrial SMPS
Description
The SRK2001A controller implements a control
scheme specific for secondary side synchronous
rectification in LLC resonant converters that use a
transformer with center tap secondary winding for
full wave rectification.
It provides two high current gate drive outputs,
each capable of directly driving N-channel power
MOSFETs. Each gate driver is controlled
separately and an interlock logic circuit prevents
the two synchronous rectifier MOSFETs from
conducting simultaneously.
The driver high-level voltage is clamped to 11 V in
order to avoid providing excessive gate charge to
SR MOSFETs, in case the device is supplied at
higher VCC voltages.
The control scheme in this IC provides for each
synchronous rectifier being switched on as the
corresponding half-winding starts conducting and
switched off as its current goes to zero.
The turn-on logic with adaptive masking time (up
to 10% of clock cycle) and innovative adaptive
turn-off logic allow maximizing the conduction
time of the SR MOSFETs, eliminating the need of
the parasitic inductance compensation circuit.
The low consumption mode of the device allows
to meet the most stringent requirement for
converter power consumption in light-load and no
load conditions.
A noticeable feature is the very low external
component count required.
Table 1. Order codes
Part number
Package
Packing
SRK2001A
SRK2001ATR
SSO10P
Tube
Tape and reel
June 2016
This is information on a product in full production.
DocID029495 Rev 1
1/20
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