AAT1153

PRODUCT DATASHEET AAT1 153 2A Step-Down Converter General Description The AAT1153 SwitchReg™ is a 1.2MHz constant frequency current mode PWM step-down converter. It is ideal for portable equipment requiring very high current up to 2A from single-cell Lithium-ion batteries while still achieving over 90% efficiency during peak load conditions. The AAT1153 also can run at 100% duty cycle for low dropout operation, extending battery life in portable systems while light load operation provides very low output ripple for noise sensitive applications. The AAT1153 can supply up to 2A output load current from a 2.5V to 5.5V input voltage and the output voltage can be regulated as low as 0.6V. The high switching frequency minimizes the size of external components while keeping switching losses low. The internal slope compensation setting allows the device to operate with smaller inductor values to optimize size and provide efficient operation. The AAT1153 is available in adjustable (0.6V to VIN) and fixed (1.8V) output voltage versions. The device is available in a Pb-free, 3mm x 3mm 10-lead TDFN package and is rated over the -40°C to +85°C temperature range. Features • • • • • • • • • • • • • • Input Voltage Range: 2.5V to 5.5V Output Voltages from 0.6V to VIN 2A Output Current High Efficiency: Up to 95% 1.2MHz Constant Switching Frequency Low RDS(ON) Internal Switches: 0.15Ω Allows Use of Ceramic Capacitors Current Mode Operation for Excellent Line and Load Transient Response Short-Circuit and Thermal Fault Protection Soft Start Low Dropout Operation: 100% Duty Cycle Low Shutdown Current: ISHUTDOWN < 1μA TDFN33-10 Package -40°C to +85°C Temperature Range Applications • • • • • • Cellular Phones Digital Cameras DSP Core Supplies PDAs Portable Instruments Smart Phones Typical Application VIN 2 .5V-5.5V L1 2.2μH VOUT 1.8V, 2A 1 2 EN IN AIN LX 8 7 5 10 9 C1 22μF 3 AAT1153-1.8 LX OUT C2 22μF 6 AGND 4 AGND PGND PGND 1153.2008.02.1.2 www.analogictech.com 1 PRODUCT DATASHEET AAT1 AAT1 153 2A Step-Down Converter Pin Descriptions Pin # 1 2 3 4, 6 5 7, 8 9, 10 Symbol EN IN AIN AGND FB/OUT LX PGND EP Function Enable pin. Active high. In shutdown, all functions are disabled drawing