mc74hc238a ON Semiconductor, mc74hc238a Datasheet - Page 5

• Manufacturer Part Number: mc74hc238a
• Description: 1-of-8 Decoder/ Demultiplexer
• Manufacturer: ON Semiconductor

ADDRESS INPUTS
A0, A1, A2 (Pins 1, 2, 3)
determine which of the eight outputs is active−low.
CONTROL INPUTS
CS1, CS2, CS3 (Pins 6, 4, 5)
at a low level, the chip is selected and the outputs follow the
Address inputs. These inputs, when the chip is selected,
Chip select inputs. For CS1 at a high level and CS2, CS3
OUTPUT Y
OUTPUT Y
CS2, CS3
INPUT A
INPUT
t
PLH
90%
50%
10%
50%
50%
VALID
90%
50%
t
10%
f
Figure 3.
Figure 5.
t
PHL
t
THL
VALID
t
PHL
t
r
t
PLH
SWITCHING WAVEFORMS
t
TLH
PIN DESCRIPTIONS
http://onsemi.com
V
GND
V
GND
CC
CC
5
INPUT CS1
Address inputs. For any other combination of CS1, CS2, and
CS3, the outputs are at a logic high.
OUTPUTS
Y0 − Y7 (Pins 15, 14, 13, 12, 11, 10, 9, 7)
high level when addressed and the chip is selected. These
outputs remain low when not addressed or the chip is not
selected.
OUTPUT Y
Active−high Decoded outputs. These outputs assume a
t
PHL
*Includes all probe and jig capacitance
t
THL
10%
DEVICE
UNDER
Figure 6. Test Circuit
50%
TEST
90%
90%
50%
t
10%
r
Figure 4.
OUTPUT
TEST POINT
t
f
C
L
t
PLH
*
t
TLH
V
GND
CC