 GENERAL DESCRIPTION

The AX3902 is a high efficiency, 2A current mode synchronous step down DC/DC converter with a wide input voltage range from 4.5V to 18V. The device integrates high side and low si de MOSFETs to achieve high efficiency conversion.

The current mode architecture supports fast transient response and internal compensation. The AX3902 provides complete fault protection including input under voltage lockout output short circuit protec tion, over current protection, and thermal shutdown. The switching frequency is internally set at 500kHz. AX3902 have different operation modes:

AX3902 is automatic PSM/PWM mode

To improve the light load efficiency, AX3902 has proprietary light load p ower saving mode (PSM) to minimize the switching loss by reducing the switching frequency.

The AX3902 is available in the SOT-23-6L package.

 FEATURES

- Input Voltage Supply Range from 4.5V to 18V

- +/-2% 0.8V Feedback Voltage Accuracy

- Adjustable Output Vol tage from 0.8V to 12V

- 500 k Hz Constant Frequency Operation

- Built in 120mΩ/80mΩ Power Switch

- Continuous Output Current up to 2A

- High Efficiency up to 95%

- Internal Soft-Start

- Current Mode Operation

- Input Under Voltage Lockout (UVLO)

- Over temperature Protection

- Over current Protection

- Over Load and Short Circuit Protection

- Thermal Shutdown Protection

- Available in a Small SOT-23-6L Package

- RoHS and Halogen Free compliance

 Applications

- Wireless and DSL Card

- Portable/Handheld Device

- STB, TV, Sound Bar, MP3 Player

- Microprocessor and DSP Core Supply