MAX1734

Features:

250mA Guaranteed Output Current
Synchronous Rectifier for Over 90% Efficiency
Tiny 5-Pin SOT23 Package
40µA Quiescent Supply Current
0.01µA Logic-Controlled Shutdown
Up to 1.2MHz Switching Frequency
Fixed 1.8V or 1.5V Outputs (MAX1734)
Adjustable Output Voltage (MAX1733)
±1.5% Initial Accuracy
2.7V to 5.5V Input Range
Soft-Start Limits Startup Current

Application

Cellular, PCS, and Cordless Telephones
PDAs, Palmtops, and Handy-Terminals
Battery-Powered Equipment


Pinout




Specifications

IN, SHDN to GND....................................................-0.3V to +6V
OUT, FB, LX to GND....................................-0.3V to (V_IN + 0.3V)
OUT Short Circuit to GND.........................................Continuous
Continuous Power Dissipation (TA = +70°C)
5-Pin SOT23 (derate 7.1mW/°C above +70°C)...........571mW
Operating Temperature Range .....................-40°C to +85°C
Junction Temperature..................................................+150°C
Storage Temperature Range ......................-65°C to +150°C
Lead Temperature (soldering, 10s) ............................+300°C


Description

The MAX1733/MAX1734 step-down DC-DC converters deliver over 250mA to outputs as low as 1.25V. These converters use a unique proprietary current-limited control scheme that achieves over 90% efficiency. These devices maintain extremely low quiescent supply current (40µA), and their high 1.2MHz (max) operating fre-quency permits small, low-cost external components. This combination of features makes the MAX1733/MAX1734 excellent high efficiency alternatives to linear regulators in space-constrained applications.