SRK2001

SRK2001 Adaptive Synchronous Rectification Controller For LLC Resonant Converter The SRK2001 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 driving one or more 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 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 innovative turn-on logic with adaptive masking time and the adaptive turn-off logic allows for maximizing the conduction time of the SR MOSFETs eliminating the need for the parasitic inductance compensation circuit. The low consumption mode of the device allows for meeting the most stringent requirement for converter power consumption in light-load / no-load conditions.

Features:

Secondary side synchronous rectification controller optimized for LLC resonant converter

Adaptive turn-off logic

Turn-on logic with adaptive masking time

Auto-compensation of parasitic inductance

Low consumption mode: 50 ϤA quiescent current

VCC operating voltage range 4.5 to 32 V

High voltage drain-to-source Kelvin sensing for each SR MOSFET

Operating frequency up to 500 kHz

35 ns total delay at turn-off

Protection against current reversal

Safe management of load transient, light-load and startup conditions

Intelligent automatic sleep mode at light-load with user programmable enter/exit load levels, with soft transitions and function disable

Programmable exit load levels from burst mode

Compatible with standard level MOSFETs

SSOP10 package

Applications:

AC-DC adapters

All-in -one PC

High-end flat panel TV