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Texas Instruments SN75493 aka SN27422, SN27915

Features

The SN75493 provides the same basic function as the SN75491 but with some key differences:

* Operates from lower Vcc voltages, as low as 3.2V
* An enable input is provided to allow display blanking

The SN75493 is preferred on designs running on 3 batteries and is typically found in early designs with additional segment drivers (TMS0120).

Usage

SR-10 and other early LED calculators

Technical Specification

Item Min Typ Max Unit Comments
VCC 3.2 7.2 8.8 V  
VSS 6.5 7.2 8.8 V  
IL  -8 -13   mA VI=6.5 V, VO=2.2 V, RL =50 Ohm
IL     -0.1 mA  
VI-VD     10 V  

Housing

The SN75493 uses a standard DIP-16 package.

Pin Description

Pin IO Function Pin IO Function
1 V VSS 16 V VCC
2 I Current set 1 15 I Current set 4
3 O Segment output 1 14 O Segment output 4
4 I Segment input 1 13 I Segment input 4
5 I Segment input 2 12 I Segment input 3
6 O Segment output 2 11 O Segment output 3
7 I Current set 2 10 I Current set 3
8 V GND 9 I Enable drivers

 

If you have additions to the above datasheet please email: joerg@datamath.org.

Joerg Woerner, May 23, 2002. No reprints without written permission.