ACT4533A/B-001 ACT4533A/B Rev 0, 14-Aug-13 Wide-Input Sensorless CC/CV Step-Down DC/DC Converter FEATURES APPLICATIONS 40V Input Voltage Surge Car Charger/ Adaptor 36V Steady State Operation Rechargeable Portable Devices Up to 3.5A output current General-Purpose CV/CC Power Supply Output Voltage up to 12V GENERAL DESCRIPTION 125kHz Switching Frequency Eases EMI Design ACT4533A/B is a wide input voltage, high efficiency 91% Efficiency (Vout=5V 2.4A at Vin=12V) ActiveCC step-down DC/DC converter that operates Stable with Low-ESR Ceramic Capacitors to in either CV (Constant Output Voltage) mode or CC Allow Low-Profile Designs (Constant Output Current) mode. ACT4533A/B provides up to 3.5A output current at 125kHz Integrated Over Voltage Protection switching frequency. Excellent EMI Performance ActiveCC is a patented control scheme to achieve Patented ActiveCC Sensorless Constant Current high-accuracy sensorless constant current control. Control Improves Efficiency and Lowers Cost. ActiveCC eliminates the expensive, high accuracy Resistor Programmable current sense resistor, making it ideal for CLA applications. Current Limit from 1.5A to 4.0A ACT4533A/B integrates adaptive gate drive to Patented Cable Compensation from 0 to achieve excellent EMI performance passing 0.25 EN55022 Class B EMC standard without adding 7.5% CC Accuracy additional EMI components while maintaining high Compensation of Input /Output Voltage Change conversion efficiency. Temperature Compensation Protection features include cycle-by-cycle current Independent of inductance and Inductor DCR limit, thermal shutdown, and frequency foldback at short circuit. The devices are available in a SOP- 2% Feedback Voltage Accuracy 8EP package and require very few external devices Advanced Feature Set for operation. Integrated Soft Start The only difference between ACT4533A and Thermal Shutdown ACT4533B is that Pin 7 provides OVP for Secondary Cycle-by-Cycle Current Limit ACT4533A and EN/OVP for ACT4533B. Protection Against Shorted ISET Pin SOP-8EP Package CC/CV Curve 6.0 V = 24V IN 5.0 V = 18V IN 4.0 3.0 V = 12V IN 2.0 1.0 0.0 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 Output Current (A) TM Innovative Power - 1 - www.active-semi.com Copyright 2013 Active-Semi, Inc. Output Voltage (V) ACT4533A/B Rev 0, 14-Aug-13 ORDERING INFORMATION OPERATION AMBIENT OVP/EN PART NUMBER PACKAGE PINS PACKING TEMPERATURE RANGE PIN ACT4533AYH-T -40C to 85C OVP SOP-8EP 8 TAPE & REEL ACT4533BYH-T -40C to 85C OVP/EN SOP-8EP 8 TAPE & REEL PIN CONFIGURATION PIN DESCRIPTIONS PIN NAME DESCRIPTION High Side Bias Pin. This provides power to the internal high-side MOSFET gate driver. 1 HSB Connect a 22nF capacitor from HSB pin to SW pin. Power Supply Input. Bypass this pin with a 10F ceramic capacitor to GND, placed as 2 IN close to the IC as possible. 3 SW Power Switching Output to External Inductor. Ground. Connect this pin to a large PCB copper area for best heat dissipation. Return 4 GND FB, COMP, and ISET to this GND, and connect this GND to power GND at a single point for best noise immunity. Feedback Input. The voltage at this pin is regulated to 0.808V. Connect to the resistor 5 FB divider between output and GND to set the output voltage. 6 COMP Error Amplifier Output. This pin is used to compensate the converter. ACT4533A:OVP input. If the voltage at this pin exceeds 0.8V, the IC shuts down high- side switch. There is a 4A pull-up current at this pin. 7 EN/OVP ACT4533B: EN/OVP input. If the voltage at this pin is below 0.65V, the IC remains shut-off if the Voltage at this pin exceeds 2.26V, the IC shuts down high side switch. There is a 4A pull-up current at this pin. Output Current Setting Pin. Connect a resistor from ISET to GND to program the 8 ISET output current. Heat Dissipation Pad. Connect this exposed pad to large ground copper area with Exposed Pad copper and vias. TM Innovative Power - 2 - www.active-semi.com Copyright 2013 Active-Semi, Inc.