1FEATURES

2• High Accuracy 5V Specified 100mA Output

• Extremely Low Quiescent Current

• Low Dropout Voltage

• Extremely Tight Load and Line Regulation

• Very Low Temperature Coefficient

• Use as Regulator or Reference

• Needs Only 1μF for Stability

• Current and Thermal Limiting

LP4951C VERSIONS ONLY

• Error Flag Warns of Output Dropout

• Logic-controlled Electronic Shutdown

• Output Pogrammable From 1.24 to 29V

DESCRIPTION

The LP4950C and LP4951C are micropower voltage

regulators with very low quiescent current (75μA typ.)

and very low dropout voltage (typ. 40mV at light loads

and 380mV at 100mA). They are ideally suited for

use in battery-powered systems. Furthermore, the

quiescent current of the LP4950C/LP4951C increases only slightly in dropout, prolonging battery

life.

The LP4950C in the popular 3-pin TO-92 package is

pin compatible with older 5V regulators. The 8-lead

LP4951C is available in a plastic surface mount

package and offers additional system functions.

One such feature is an error flag output which warns

of a low output voltage, often due to falling batteries

on the input. It may be used for a power-on reset. A

second feature is the logic-compatible shutdown input

which enables the regulator to be switched on and

off. Also, the part may be pin-strapped for a 5V

output or programmed from 1.24V to 29V with an

external pair of resistors.

Careful design of the LP4950C/LP4951C has

minimized all contributions to the error budget. This

includes a tight initial tolerance (.5% typ.), extremely

good load and line regulation (.05% typ.) and a very

low output voltage temperature coefficient, making

the part useful as a low-power voltage reference.