ACT512 Rev 4, 13-Feb-14 TM ActiveQR Quasi-Resonant PWM Controller ACT512 integrates comprehensive protection. In FEATURES case of over temperature, over voltage, winding CCM and Quasi-Resonant Operation short, current sense resistor short, open loop and overload conditions, it would enter into auto restart Adjustable up to 75kHz Switching Frequency mode including Cycle-by-Cycle current limiting. OCP/OLP Protection ACT512 is to achieve no overshoot and very short Integrated Patented Frequency Foldback rise time even with a big capacitive load with the Technique built-in fast and soft start process. Integrated Patented Line Compensation In full load condition, ACT512 is able to be designed to work in both CCM mode and DCM Built-in Soft-Start Circuit mode to meet different types of applications. Quasi- Line Under-Voltage, Thermal, Output Over- Resonant (QR) operation mode can improve voltage, Output Short Protections efficiency during DCM operation, and reduce EMI Current Sense Resistor Short Protection and further reduce the components in input filter. Transformer Winding Short Protection ACT512 is ideal for applications up to 60 Watts. 100mW Standby Power Figure 1: Complies with Global Energy Efficiency and Simplified Application Circuit CEC Average Efficiency Standards Tiny SOT23-6 Packages APPLICATIONS AC/DC Adaptors/Chargers for Cell Phones, Cordless Phone, PDAs, E-books Adaptors for Portable Media Player, DSCs, Set-top boxes, DVD players, records Linear Adapter Replacements GENERAL DESCRIPTION The ACT512 is a high performance peak current TM mode PWM controller. ACT512 applies ActiveQR and frequency foldback technique to reduce EMI and improve efficiency. ACT512s maximum design switching frequency is set at 75kHz. Very low standby power, good dynamic response and accurate voltage regulation is achieved with an opto-coupler and the secondary side control circuit. The idle mode operation enables low standby power of 100mW with small output voltage ripple. TM By applying frequency foldback and ActiveQR technology, ACT512 increases the average system efficiency compared to conventional solutions and exceeds the latest ES2.0 efficiency standard with good margin. TM Innovative Power - 1 - www.active-semi.com Active-Semi ProprietaryFor Authorized Recipients and Customers Copyright 2014 Active-Semi, Inc. TM ActiveQR is a trademark of Active-Semi. ACT512 Rev 4, 13-Feb-14 ORDERING INFORMATION PACKING PART NUMBER TEMPERATURE RANGE PACKAGE PINS TOP MARK METHOD ACT512US-T -40C to 85C SOT23-6 6 TUBE & REEL FSHT PIN CONFIGURATION SOT23-6 ACT512US PIN DESCRIPTIONS PIN NAME DESCRIPTION Current Sense Pin. Connect an external resistor (R ) between this pin and ground to set peak CS 1 CS current limit for the primary switch. 2 GND Ground. 3 GATE Gate Drive. Gate driver for the external MOSFET transistor. 4 VDD Power Supply. This pin provides bias power for the IC during startup and steady state operation. Valley Detector Pin. Connect this pin to a resistor divider network from the auxiliary winding to 5 VDET detect zero-crossing points for valley turn on operation. 6 FB Feedback Pin. Connect this pin to optocouplerss collector for output regulation. TM Innovative Power - 2 - www.active-semi.com Active-Semi ProprietaryFor Authorized Recipients and Customers Copyright 2014 Active-Semi, Inc. TM ActiveQR is a trademark of Active-Semi.