NOT RECOMMENDED FOR NEW DESIGN USE APR348 APR346 SECONDARY SIDE SYNCHRONOUS RECTIFICATION CONTROLLER Description Pin Assignments The APR346 is a secondary side MOSFET driver for synchronous (Top View) rectification, supports CCM, DCM and Quasi-Resonant Flyback Topologies. Pin 1 Mark The synchronous rectification can effectively reduce the secondary side rectifier power dissipation and provide high performance solution. By sensing primary MOSFET gate-to-source voltage, the APR346 AREF 1 6 DRISR can output ideal drive signal with less external components. It can provide high performance solution for 5V to 20V output voltage CCM 2 5 GND application. The APR346 is available in SOT26 package. 3 4 VCC VDET Features SOT26 Synchronous Rectification for CCM, DCM Operation Flyback Eliminate Resonant Ring Interference Fewest External Components Applications Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Adapters/Chargers for Cell/Cordless Phones, ADSL Modems, Halogen and Antimony Free. Green Device (Note 3) MP3 and Other Portable Apparatus Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. 2. See VCC APR346 Pin Descriptions Pin Number Pin Name Function Program a voltage reference with a resistor from AREF to GND, to enable synchronous rectification 1 AREF MOSFET drive signal 2 GND Ground 3 VDET SR MOS drain-to-source voltage sense input, connected to drain pin of SR MOSFET through a resistor 4 VCC Power supply, connected with system output 5 CCM Primary trigger signal sense input 6 DRISR Synchronous rectification MOSFET Gate drive Functional Block Diagram VCC 4 VDD Test Fault Power Regulator V REF Mode Mode OK I AREF 1 AREF VCC Integrator S Q (VDET- S Q 6 VCC)dt Drive DRISR R R V THON Gate Monitor LEB 3 Time VDET V THOFF V THCCM 2 5 CCM GND 2 of 11 September 2020 APR346 Diodes Incorporated www.diodes.com Document number: DS38999 Rev. 7 - 3