General Description
The MAX730A/MAX738A/MAX744A are 5V-output CMOS, step-down switching regulators. The MAX738A/MAX744A accept inputs from 6V to 16V and deliver 750mA. The MAX744A guarantees 500mA load capability for inputs above 6V and has tighter oscillator frequency limits for low-noise (radio) applications. The MAX730A accepts inputs between 5.2V and 11V and delivers 450mA for inputs above 6V. Typical efficiencies are 85% to 96%. Quiescent supply current is 1.7mA and only 6µA in shutdown.
Pulse-width modulation (PWM) current-mode control provides precise output regulation and excellent transient responses. Output voltage accuracy is guaranteed to be ±5% over line, load, and temperature variations. Fixed-frequency switching allows easy filtering of output ripple and noise, as well as the use of small external components. These regulators require only a single inductor value to work in most applications, so no inductor design is necessary.
The MAX730A/MAX738A/MAX744A also feature cycle by-cycle current limiting, overcurrent limiting, undervoltage lockout, and programmable soft-start protection.

Features
♦ 750mA Load Currents (MAX738A/MAX744A)
♦ High-Frequency, Current-Mode PWM
♦ 159kHz to 212.5kHz Guaranteed Oscillator
   Frequency Limits (MAX744A)
♦ 85% to 96% Efficiencies
♦ 1.7mA Quiescent Current
♦ 6µA Shutdown Supply Current
♦ Single Preselected Inductor Value,
   No Component Design Required
♦ Overcurrent, Soft-Start, and Undervoltage
   Lockout Protection
♦ Cycle-by-Cycle Current Limiting
♦ 8-Pin DIP/SO Packages (MAX730A)

Applications
   Portable Instruments
   Cellular Phones and Radios
   Personal Communicators
   Distributed Power Systems
   Computer Peripherals