m74hc161 STMicroelectronics, m74hc161 Datasheet - Page 2

• Manufacturer Part Number: m74hc161
• Description: Synchronous Presettable 4-bit Counter
• Manufacturer: STMicroelectronics

M74HC161
INPUT AND OUTPUT EQUIVALENT CIRCUIT
TRUTH TABLE
X : Don’t Care
A, B, C, D : Logic level of data inputs
Carry : CARRY = TE·Q
LOGIC DIAGRAM
This logic diagram has not be used to estimate propagation delays
2/12
CLEAR
H
H
H
H
H
L
LOAD
X
H
H
H
X
L
A
INPUTS
·Q
PE
B
X
X
X
H
X
L
·Q
C
·Q
D
TE
X
X
X
H
X
L
CLOCK
X
QA
A
L
NO CHANGE
NO CHANGE
NO CHANGE
QB
PIN DESCRIPTION
COUNT UP
B
OUTPUTS
L
14, 13, 12,
3, 4, 5, 6
PIN No
10
11
15
16
1
2
7
9
8
QC
C
L
A, B, C, D
QA to QD
SYMBOL
CLOCK
CARRY
CLEAR
LOAD
QD
GND
D
Vcc
L
PE
TE
Asynchronous Master
Reset
Clock Input (LOW to
HIGH, Edge-triggered)
Data Inputs
Count Enable Input
Count Enable Carry Input
Parallel Enable Input
Flip Flop Outputs
Terminal Count Output
Ground (0V)
Positive Supply Voltage
NAME AND FUNCTION
PRESET DATA
RESET TO "0"
NO COUNT
NO COUNT
NO COUNT
FUNCTION
COUNT