TLH7754

March 1989

LM104LM204LM304 Negative Regulator

General Description

The LM104 series are precision voltage regulators which

can be programmed by a single external resistor to supply

any voltage from 40V down to zero while operating from a

single unregulated supply They can also provide 001-per-

cent regulation in circuits using a separate floating bias

supply where the output voltage is limited only by the

breakdown of external pass transistors Although designed

primarily as linear series regulators the circuits can be used

as switching regulators current regulators or in a number of

other control applications Typical performance characteris-

tics are

Y

Subsurface zener reference

Y

1 mV regulation no load to full load

Y

001%V line regulation

Y

02 mVV ripple rejection

Y

03% temperature stability over military temperature

range

The LM104 series is the complement of the LM105 positive

regulator intended for systems requiring regulated negative

voltages which have a common ground with the unregulated

supply By themselves they can deliver output currents to

25 mA but external transistors can be added to get any

desired current The output voltage is set by external resis-

tors and either constant or foldback current limiting is made

available

a

125 C military temperature range The LM204 is specified

Schematic Diagram

TLH7754 – 1

C1995 National Semiconductor Corporation

RRD-B30M115Printed in U S A