TLF5851

May 1986

DS8973 9-Digit LED Driver

General Description

The DS8973 is a 9-digit driver designed to operate from

3-cell battery supplies Each driver will sink 100 mA to less

than 07V when driven by only 01 mA Each input is blocked

by diodes so that the input can be driven below ground with

virtually no current drain This is especially important in cal-

culator systems employing a DC-to-DC converter on the

negative side of the battery If the converter were on the

positive side of the battery the converter would have to

handle all of the display current as well as the MOS calcula-

tor chip current But if it is on the negative side it only has

to handle the MOS current The DS8973 is designed for the

more efficient operating mode

Features

Y

Nine complete digit drivers

Y

Built-in low battery indicator

Y

High current outputs100 mA

Y

Straight through pin out for easy board layout

Equivalent Circuit Diagrams

Typical Driver Circuit

TLF5851 – 1

Typical DP Out Circuit

TLF5851 – 2

Connection Diagram

Dual-In-Line Package

TLF5851 – 3

Top View

Order Number DS8973N

See NS Package Number N22A

C1995 National Semiconductor Corporation

RRD-B30M105Printed in U S A