DS7880_11 Datasheet, PDF (2/8 Pages) Texas Instruments – High Voltage 7-Segment Decoder/Driver

March 1988
DS7880 DS8880 High Voltage 7-Segment Decoder Driver
General Description
The DS7880 DS8880 is custom designed to decode four gram resistor (R_P) from V_CC to the Program input in accord-
lines of BCD and drive a gas-filled seven-segment display ance with the programming curve The circuit design pro-
tube
vides a one-to-one correlation between program input cur-
Each output constitutes a switchable adjustable current ^{rent and b-segment output current}
sink which provides constant current to the tube segment The Blanking Input provides unconditional blanking of any
even with high tube anode supply tolerance or fluctuation output display while the Ripple Blanking pins allow simple
These current sinks have a voltage compliance from 3V to leading- or trailing-zero blanking
at least 80V typically the output current varies 1% for out-
put voltage changes of 3 to 50V Each bit line of the decod-
er switches a current sink on or off as prescribed by the
input code Each current sink is ratioed to the b-output cur-
rent as required for even illumination of all segments
Output currents may be varied over the 0 2 to 1 5 mA range
for driving various tube types or multiplex operation The
output current is adjusted by connecting an external pro-
Features
Y _{Current sink outputs}
Y _{Adjustable output current 0 2 to 1 5 mA}
Y _{High output breakdown voltage 110V typ}
Y _{Suitable for multiplex operation}
Y _{Blanking and Ripple Blanking provisions}
Y _{Low fan-in and low power}
Obsolete ^LogicDiagram
TL F 5845 – 1
C1995 National Semiconductor Corporation TL F 5845
RRD-B30M105 Printed in U S A