APR348 SECONDARY SIDE SYNCHRONOUS RECTIFICATION CONTROLLER Description Pin Assignments The APR348 is a secondary-side MOSFET driver for synchronous (Top View) rectification, which can effectively reduce the secondary-side rectifier power dissipation and provide a high-performance solution. The APR348 can support continuous or discontinuous conduction VCC 1 6 VDET mode (CCM and DCM) and quasi-resonant flyback operation based on a MOSFET operating on-time control technology. This technology GND 2 5 DRISR provides minimized turn-on and turn-off delay to reduce power loss and keep safe operation without adding any external components or Rx 3 4 VDD circuitry. The APR348 can configure into high-side or low-side application to fit various design requirement. It also has specialized light load mode and SOT26 (Type CJ) determines safe driver pulse generation through load detection. The VDD power supply can be charged by VDET or VCC, which means it can be charged by internal PLR (Pulse linear regulator) at low output voltage and charged by internal LDO at high output voltage. Therefore, it can provide a wide output operation voltage from 3.3V to 20V. The APR348 is available in SOT26 (Type CJ) package. Features Applications Synchronous Rectification Controller Suited for High-Side and Low-Side Flyback Converters in Adapters/Chargers for Cell/Cordless Phones, ADSL Modems, MP3 CCM/DCM/QR Operation and Other Portable Apparatus Minimized Turn-On and Turn-Off Delay Internal UVLO Protection Light Load Mode Control Eliminate False Turn-On with Resonant Ring Fewest External Components Moisture Sensitivity: MSL Level 1 per J-STD-020 Terminals: Finish Matte Tin Plated Leads, Solderable per M2003 JESD22-B102, Method 208 Weight: 0.016/0.017 grams (Approximate) Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) For automotive applications requiring specific change control (i.e. parts qualified to AEC-Q100/101/200, PPAP capable, and manufactured in IATF 16949 certified facilities), please contact us or your local Diodes representative. APR348 Typical Applications Circuit V OUT V OUT Q2 APR348 C2 C2 VDET VCC APR348 Rx VDD DRISR VDET R1 DRISR GND C1 GND VDD VCC Rx R1 C1 Q1 Q1 Q2 High-Side Application Low-Side Application Pin Descriptions Pin Number Pin Name Function 1 VCC Internal Linear Regulator Input 2 GND Ground, also used as FET source sense reference for VDET 3 Rx External fixed resistor for Accurate Turn-On Signal Linear Regulator Output. It provides bias voltage for the internal logic circuit and the MOSFET driver. 4 VDD Connect this pin to a capacitor. Synchronous Rectification MOSFET Gate Drive 5 DRISR 6 VDET Synchronous Rectification MOSFET Drain Voltage Sense Input Functional Block Diagram VCC 1 VDET VCC Power Power Management Management 6 VDET 4 VDD Power V / REF ON/OFF I BIAS VDET Sensing 5 DRISR Control SR 3 Core Driver Rx 2 GND 2 of 9 APR348 March 2021 Diodes Incorporated www.diodes.com Document number: DS42016 Rev. 5 - 2 NEW PRODUCT