AS1003

AS1003 FEATURES Precision feedback reference voltage: 0.5V (2%) Wide supply voltage operating range: 3.6 to 20V Low current consumption: 3.0mA Internal fixed oscillator frequency: Typ. 360KHz Programmable Soft-Start function (SS) Short Circuit Shutdown and Auto Re-start function(ARSCP) Built-in P-MOSFET for 3A loading capability Package: SOP8 360KHz, 3A PWM Buck Converter GENERAL DESCRIPTION The AS1003 is a buck topology of switching regulator for wide operating voltage applications field. The AS1003 includes a high current P-MOSFET, high precision reference (0.5V) for comparing output voltage with feedback amplifier, an internal dead-time control and oscillator for controlling the maximum duty cycle and PWM frequency, and has power-on programmable soft start time and short circuit PMOS turn-off and auto re-start protection functions. APPLICATIONS PC Monitors Distributed Power Systems Battery Charger Pre-Regulator for Linear Regulators TYPICAL APPLICATION Figure1. 12V to 3.3V/2A Typical Application Circuit EFFICIENCY(% EFFICIENCY 100 VOUT=5.0V 95 90 85 80 75 70 0.5 VOUT=3.3V VIN=12V TA=25℃ 1 1.5 2 2.5 LOAD CURRENT(A) 3 AS1003 Preliminary _08/03/08 www.anisem.com 1 AS1003 360KHz, 3A PWM Buck Converter ABSOLUTE MAXIMUM RATINGS (Note1) VIN Voltage Range……………..…….. 3V to 20V IOUT Output Current ….………………..………3A Error Amplifier IN-……………..…. -0.3V to 1.2V PD Power Dissipation (TA=25℃)……..… 650mW Operating Temperature Range .… -40℃ to 85℃ Storage Temperature Range …....