HD74LS247 Datasheet, PDF (2/8 Pages) Hitachi Semiconductor – 8CD-to-Seven-Segment Decoders/Drivers(with 15V outputs)

HD74LS247
Pin Arrangement
B1
Inputs
C2
LT 3
BI/RBO 4
RBI 5
D6
Inputs
A7
GND 8
B
f
C
g
LT
a
BI/BRO b
RBI
c
D
d
A
e
16 V_CC
15 _f
14 _g
13 _a
12 _{b Outputs}
11 _c
10 _d
9e
(Top view)
Function Table
Decimal
Inputs
BI/
or
Function ^{LT RBI D}
C
B
A RBO a
b
Outputs
c
d
e
f
Note
g
0
H
H
L
L
L
L
H ON ON ON ON ON ON OFF
1
H
X
L
L
L
H
H OFF ON ON OFF OFF OFF OFF
2
H
X
L
L
H
L
H ON ON OFF ON ON OFF ON
3
H
X
L
L
HH
H ON ON ON ON OFF OFF ON
4
H
X
L
H
L
L
H OFF ON ON OFF OFF ON ON
5
H
X
L
H
L
H
H ON OFF ON ON OFF ON ON
6
H
X
L
HH
L
H ON OFF ON ON ON ON ON
7
H
X
L
HHH
H ON ON ON OFF OFF OFF OFF
1
8
H
X
H
L
L
L
H ON ON ON ON ON ON ON
9
H
X
H
L
L
H
H ON ON ON ON OFF ON ON
10
H
X
H
L
H
L
H OFF OFF OFF ON ON OFF ON
11
H
X
H
L
H
H
H OFF OFF ON ON OFF OFF ON
12
H
X
HH
L
L
H OFF ON OFF OFF OFF ON ON
13
H
X
H
H
L
H
H ON OFF OFF ON OFF ON ON
14
H
X
HHH
L
H OFF OFF OFF ON ON ON ON
15
H
X
H
H
H
H
H OFF OFF OFF OFF OFF OFF OFF
BI
X
X
XXXX
L OFF OFF OFF OFF OFF OFF OFF 2
RBI
H
L
L
L
L
L
L OFF OFF OFF OFF OFF OFF OFF 3
LT
L
X
XXXX
H ON ON ON ON ON ON ON 4
H; high level, L; low level, X; irrelevant
Notes: 1. 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.
2. When a low logic level is applied directly to the blanking input (BI), all segment outputs are off regardless of
the level of any other input.
3. When ripple-blanking input (RBI) and inputs A, B, C, and D are a low level with the lamp test input high, all
segment outputs go off and the ripple-blanking output (RBO) goes to a low level (response condition).
4. When a blanking input ripple blanking input (BI/RBO) is open or held high and a low is applied to the lamp-
test input, all segment outputs are on.
Rev.3.00, Jul.15.2005, page 2 of 7