AP3422DNTR-G1 Diodes Incorporated

Preliminary Datasheet Dual 1.1MHz, 800mA Synchronous DC-DC Buck Converter AP3422 General Description Features The AP3422 contains two independent 1.1MHz fixed High Efficiency: up to 95% frequency, current mode, PWM synchronous buck Output Current on Each Channel: 800mA (step-down) DC-DC converters, each of them is Input Voltage Range: 2.5V to 5.5V capable of driving a 800mA load with high efficiency, Fixed 1.1MHz Frequency excellent line and load regulation. Each converter 100% Duty Cycle in Dropout integrates a main switch and a synchronous switch Built-in Short Circuit Protection without an external Schottky diode. It is ideal for Built-in Thermal Shutdown Function powering portable equipment that runs from a single Built-in Current Limit Function Li-ion battery. Shutdown Current: <1 A A standard series of inductors are available from several different manufacturers optimized for use Applications with the AP3422. This feature greatly simplifies the design of switch-mode power supplies. GPS WiFi Card This IC is available in DFN-33-10 package. Portable Media Player Digital Still and Video Cameras DFN-33-10 Figure 1. Package Type of AP3422 Feb. 2013 Rev. 1. 2 BCD Semiconductor Manufacturing Limited 1 Preliminary Datasheet Dual 1.1MHz, 800mA Synchronous DC-DC Buck Converter AP3422 Pin Configuration DN Package (DFN-33-10) Pin 1 Mark 1 10 2 9 3 8 7 4 56 Figure 2. Pin Configuration of AP3422 (Top View) Pin Description Pin Number Pin Name Function Channel 1 enable control input. Drive EN1 above 1.5V to turn on the 1 EN1 Channel 1. Drive EN1 below 0.6V to turn it off (shutdown current < 0.1A) Channel 1 feedback input. Connect FB1 to the center point of the external 2 FB1 resistor divider. The feedback voltage is 0.6V Channel 2 supply input. Bypass to GND with a 10F or greater ceramic 3 VIN2 capacitor 4 GND2 Ground 2 Channel 2 power switch output. Inductor connection to drains of the 5 SW2 internal PFET and NFET switches Channel 2 Enable Control Input. Drive EN2 above 1.5V to turn on the 6 EN2 Channel 2. Drive EN2 below 0.6V to turn it off (shutdown current < 0.1A) Channel 2 feedback input. Connect FB2 to the center point of the external 7 FB2 resistor divider. The feedback voltage is 0.6V Channel 1 supply input. Bypass to GND with a 10F or greater ceramic 8 VIN1 capacitor 9 GND1 Ground 1 Channel 1 power switch output. Inductor connection to drains of the 10 SW1 internal PFET and NFET switches Feb. 2013 Rev. 1. 2 BCD Semiconductor Manufacturing Limited 2