MAX8625A Datasheet | Maxim Integrated

19-1006; Rev 0; 3/08 High-Efficiency, Seamless Transition, Step-Up/Down DC-DC Converter General Description The MAX8625A PWM step-up/down regulator is intended to power digital logic, hard disk drives, motors, and other loads in portable, battery-powered devices such as PDAs, cell phones, digital still cameras (DSCs), and MP3 players. The MAX8625A provides either a fixed 3.3V or adjustable output voltage (1.25V to 4V) at up to 0.8A from a 2.5V to 5.5V input. The MAX8625A utilizes a 2A peak current limit. Maxim’s proprietary H-bridge topology- provides a seamless transition through all operating modes without the glitches monly seen with other devices. Four internal MOSFETs (two switches and two synchronous rectifiers) with internal pensation minimize external .. ponents. A SKIP input selects a low-noise, fixedfrequency PWM mode, or a high-efficiency skip mode where the converter automatically switches to PFM mode under light loads for best light-load efficiency. The internal oscillator operates at 1MHz to allow for a small external inductor and capacitors. The MAX8625A Features current-limit circuitry that shuts down the IC in the event of an output overload. In addition, soft-start circuitry reduces inrush current during startup. The IC also Features True Shutdown TM, which disconnects the output from the input when the IC is disabled. The MAX8625A is available in a 3mm x 3mm, 14-pin TDFN package. - - - - Features Four Internal MOSFET True H-Bridge Buck/Boost Glitch-Free, Buck-Boost Transitions Minimal Output Ripple Variation on Transitions Up to 92% Efficiency - 37µA (typ) Quiescent Current in Skip Mode - 2.5V to 5.5V Input Range - Fixed 3.3V or Adjustable Output - 1µA (max) Logic-Controlled Shutdown - - - - - - - True Shutdown Output Overload Protection Internal pensation Internal Soft-Start 1MHz Switching Frequency Thermal-Overload Protection Small 3mm x 3mm, 14-Pin TDFN Package Ordering Information PART MAX8625AETD+...