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2

Function Table

H

= HIGH level,

L

= LOW level,

X

= Don’t Care

Note 1: BI/RBO is a wire-AND logic serving as blanking input (BI) and/or ripple-blanking output (RBO).

Note 2: The blanking input (BI) must be OPEN or held at a HIGH logic level when output functions 0 through 15 are desired. The ripple-blanking input (RBI)

must be OPEN or HIGH if blanking of a decimal zero is not desired.

Note 3: When a LOW logic level is applied directly to the blanking input (BI), all segment outputs are HIGH regardless of the level of any other input.

Note 4: When ripple-blanking input (RBI) and inputs A, B, C, and D are at a LOW level with the lamp test input HIGH, all segment outputs go H and the rip-

ple-blanking output (RBO) goes to a LOW level (response condition).

Note 5: When the blanking input/ripple-blanking output (BI/RBO) is OPEN or held HIGH and a LOW is applied to the lamp-test input, all segment outputs are

L.

Logic Diagram

Decimal or

Inputs

BI/RBO

Outputs

Note

Function

LT

RBI

D

C

B

A

(Note 1)

a

b

c

d

e

f

g

0

H

H

LLL

L

H

LLL

LLL

H

1

H

X

LLL

H

H

H

L

L

H

H

H

H

2

H

X

L

LH

L

H

L

L

H

L

LH

L

3

H

X

L

LH

H

H

L

L

L

LH

H

L

4

H

X

L

HL

L

H

H

L

L

H

HL

L

5

H

X

L

HL

H

H

L

H

L

L

HL

L

6

H

X

L

H

H

L

H

H

H

L

LLL

L

7

H

X

L

HHH

H

L

L

L

H

HHH

(Note 2)

8

H

X

H

LL

L

H

LLL

LLL

L

9

H

X

H

LL

H

H

LLL

H

H

L

L

10

H

X

HL

HL

H

H

H

H

L

L

HL

11

H

X

HL

H

H

H

H

H

L

L

H

HL

12

H

X

HH

L

L

H

H

L

H

HH

L

L

13

H

X

H

H

LH

H

L

H

H

LH

L

L

14

H

X

H

H

H

L

H

H

H

H

LLL

L

15

H

X

H

HHH

H

H

HHH

HHH

BI

X

X

X

X

X

X

L

H

HHH

HHH

(Note 3)

RBI

H

L

L

L

L

L

L

H

HHH

HHH

(Note 4)

LT

L

X

X

X

X

X

H

LLL

LLL

L

(Note 5)