UTC LM317L LINEAR INTEGRATED CIRCUIT

4

QW-R101-008,A

APPLICATION INFORMATION

The UTC LM317L provides an internal reference voltage of 1.25V between the output and adjustments terminals.

This is used to set a constant current flow across an external resistor divider, giving an output voltage VO of:

µA max) and to maintain it very constant with line and load

changes. Usually, the error term IADJ. R2 can be neglected. To obtain the previous requirement, all the regulator

quiescent current is returned to the output terminal, imposing a minimum load current condition. If the load is

insufficient, the output voltage will rise. The UTC LM317L is a floating regulator, input-output differential voltage,

supplies of very high voltage with respect to ground can be regulated as long as the maximum input-output differential

is not exceeded. Furthermore, programmable regulators are easily obtainable and, by connecting a fixed resistor

between the adjustment and output, the device can be used as a precision current regulator.

LM317L

Vi

Vo

3

2

1

Vref

R1

R2

Iadj

I1

BASIC ADJUSTABLE REGULATOR