1 Features

1• 2.3-V to 30-V Input Voltage Range

• Output Voltage Adjusts from 1.23 V to 29 V

• 250-mA Output Current

• Extremely Low Quiescent Current battery•

Low Dropout Voltage

• Extremely Tight Line and Load Regulation

• Very Low Temperature Coefficient

• Current and Thermal Limiting

• Reverse Battery-Input Protection

• 50-mA (Typical) Automatic Output Discharge

• LP2953 Versions Only

– Auxiliary Comparator Included With CMOS-

and TTL-Compatible Output Levels. Can Be

Used for Fault Detection, Low-Input Line

Detection, and so on.

2 Applications

• High-Efficiency Linear Regulator

• Regulator With Undervoltage Shutdown

• Low-Dropout Battery-Powered Regulator

• Snap-ON/Snap-OFF Regulator

3 Description

The LP2952 and LP2953 are micropower voltage

regulators with very low quiescent current (130 μA typical at 1-mA load) and very low dropout voltage

(typically 60 mV at light load and 470 mV at 250-mA

load current). They are ideally suited for battery•

powered systems. Furthermore, the quiescent current increases only slightly at dropout, which prolongs

battery life.

The LP2952 and LP2953 retain all the desirable

characteristics of the LP2951, but offer increased

output current, additional features, and an improved

shutdown function.

The automatic output discharge pulls the output down

quickly when the shutdown is activated.

The error flag goes low if the output voltage drops out

of regulation.

Reverse battery-input protection is provided.

The internal voltage reference is made available for

external use, providing a low temperature coefficient

(20 ppm/°C) reference with very good line (0.03%)

and load (0.04%) regulation.