描述 Description

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 directly driving one or more N-channel power MOSFET. Each gate driver is controlled separately and an interlock logic circuit prevents the two synchronous rectifier MOSFET from conducting simultaneously.

The control scheme ensures that each synchronous rectifier is switched ON as the corresponding half-winding starts conducting and OFF as its current falls to zero.

The turn-on logic with adaptive masking time and adaptive turn-off logic allow maximizing the conduction time of the SR MOSFET, eliminating the need for a parasitic inductance compensation circuit.

The low consumption mode of the device allows meeting the most stringent requirements for converter power consumption in light-load and no-load conditions.

A very low external component count is required when using this device.

特性 Features

? Secondary side synchronous rectification controller optimized for LLC resonant converter
? Dual gate driver for N-channel MOSFET
? Adaptive turn-off logic
? Turn-on logic with adaptive masking time
? Auto-compensation of parasitic inductance
? Low consumption mode: 50 μA quiescent current
? VCC operating voltage range 4.5 V to 32 V
? High voltage drain-to-source Kelvin sensing for each SR MOSFET
? 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 MOSFET
? SSOP10 package