AP3987CT HIGH FREQUENCY PRIMARY SIDE POWER SWITCHER FOR OFF-LINE SMPS Description Pin Assignments The AP3987CT is a high performance AC/DC power switcher for (Top View) battery charger and adapter applications with a built-in high performance controller and a built-in 650V high performance MOSFET. It can meet less than 10mW standby power for Super Star GND FB 1 7 charger criteria. The device uses Pulse Frequency Modulation (PFM) OTP 2 method to build Discontinuous Conduction Mode (DCM) Flyback power supplies. D VCC 3 6 CS 5 D The AP3987CT provides accurate Constant Voltage (CV), Constant 4 Current (CC) and outstanding dynamic performance without requiring an opto-coupler. It also eliminates the need of loop compensation SO-7 circuitry while maintaining stability. The AP3987CT is equipped with built-in 0.35V output cable drop Features compensation. Primary-Side Control for Eliminating Opto-Coupler 10mW No-Load Input Power The AP3987CT has internal over temperature protection, and also Built-In 650V High Performance MOSFET provides dedicated pin for external over temperature protection. Flyback Topology in DCM Operation Built-In 0.35V Cable Compensation for CV When the AP3987CT is used with AP4341 or APR3415CT series Multiple PWM/PFM Control Mode to Improve Audio Noise and synchronous rectifier solution, better under-shoot performance and Efficiency higher conversion efficiency can be achieved. VCS Jitter to Reduce System EMI Valley-On for the Higher Efficiency and Better EMI The AP3987CT provides operating frequency dithering function to Multiple Protections: improve system EMC performance. Over Voltage Protection (OVP) Output Short Circuit Protection (SCP) The AP3987CT is packaged in SO-7. Transformer Saturation Protection (TSP) via Primary Peak Current Limitation Internal and External Over Temperature Protection (OTP) Matching AP4341 with Schottky or APR3415CT Series Applications Synchronous Rectifier Solution Adapter/Chargers for Shaver, Cell/Cordless Phones, PDAs, MP3 SO-7 Package and Other Portable Apparatus Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Standby and Auxiliary Power Supplies Halogen and Antimony Free. Green Device (Note 3) 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 AP3987CT Typical Applications Circuit D1 to D4 FR1 T1 L1 C3 R1 Np C5 Ns + + + D6 R2 C6 R8 C1 C2 D5 R3 U2 5V/1.5A Na L2 APR 3415CT DRAIN GND R10 DRAIN GND R9 U1 VDET VCC 1 7 FB GND C7 DRISR AREF 2 OTP C8 R6 R11 3 6 VCC D 4 5 R4 D CS C4 + AP3987CT R5 CY R7 5V/1.5A Solution with AP3987CT+APR3415CT Pin Descriptions Pin Number Pin Name Function 1 FB The Voltage Feedback from Auxiliary Winding 2 OTP The External Over Temperature Protection 3 VCC Supply Voltage Pin 4 CS Current Sense for Primary Side of Transformer 5, 6 D This pin is connected with an internal power MOSFETs drain 7 GND This pin is the signal reference ground 2 of 15 AP3987CT June 2019 Diodes Incorporated www.diodes.com Document number: DS41644 Rev. 2 - 2 ADVNAENWCE PDR IONDFUOCRTM ATION