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M74HC161
SYNCHRONOUS PRESETTABLE 4-BIT COUNTER
■ HIGH SPEED :
f
= 62 MHz (TYP.) at VCC = 6V
MAX
■ LOW POWER DISSIPATION:
I
=4µA(MAX.) at TA=25°C
CC
■ HIGH NOISE IMMUNITY:
V
= V
NIH
■ SYMMETRICAL OUTPUT IMPEDANCE:
|I
| = IOL = 4mA (MIN)
OH
■ BALANCED PROPAGATION DELAYS:
t
≅ t
PLH
■ WIDE OPERATING VOLTAGE RANGE:
V
(OPR) = 2V to 6V
CC
■ PIN AND FUNCTION COMPATIBLE WITH
= 28 % VCC (MIN.)
NIL
PHL
74 SERIES 161
DESCRIPTION
The M74HC161 is an high speed CMOS
SYNCHRONOUS 4-BIT BINARY
PRESETTABLE COU NTER fa bri cated wit h si licon
gate C
2
MOS technology.
The CLOCK input is active on the rising edge.
Both LOAD
and CLEAR input s are active LOW.
Presetting is synchronous on the rising edge of
the clock, the function is cleared asynchronously.
TSSOPDIP SOP
ORDER CODES
PACKAGE TUBE T & R
DIP M74HC161B1R
SOP M74HC161M1R M74HC161RM13TR
TSSOP M74HC161TTR
Two enable inputs (TE and PE) and CARRY
output are provided to enable easy cascading of
counters, which f acilities easy imp lementation of
N-bit counters without using external gates.
All inputs are equipped with protection circuits
against static discharge and transient excess
voltage.
PIN CONNECTION AND IEC LOGIC SYMBOLS
1/12July 2001
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M74HC161
INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
PIN No SYMBOL NAME AND FUNCTION
1 CLEAR
2 CLOCK
3, 4, 5, 6 A, B, C, D Data Inputs
7 PE Count Enable Input
10 TE Count Enable Carry Input
9LOAD
14, 13, 12,
11
15 CARRY Terminal Count Output
8 GND Ground (0V)
16 Vcc Positive Supply Voltage
TRUTH TABLE
QA to QD Flip Flop Outputs
Asynchronous Master
Reset
Clock Input (LOW to
HIGH, Edge-trigge red)
Parallel Enable Input
INPUTS OUTPUTS
FUNCTION
CLEAR
LOAD PE TE CLOCK QA QB QC QD
L X X X X L L L L RESET TO "0"
H L X X A B C D PRESET DATA
H H X L NO CHANGE NO COUNT
H H L X NO CHANGE NO COUNT
H H H H COUNT UP COUNT
H X X X NO CHANGE NO COUNT
X : Don’t Care
A, B, C, D : Logic level of data inputs
Carry : CARRY = TE·Q
A·QB·QC·QD
LOGIC DIAGRAM
This log i c diagram has not be used to est i m at e propagation delays
2/12
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TIMING CHART
M74HC161
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
V
V
V
I
I
OK
I
I
or I
CC
P
T
T
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied
(*) 500mW at 65
Supply Voltage
CC
DC Input Voltage -0.5 to VCC + 0.5
I
DC Output Voltage -0.5 to VCC + 0.5
O
DC Input Diode Current
IK
DC Output Diode Current
DC Output Current
O
DC VCC or Ground Current
GND
Power Dissipation
D
Storage Temperature
stg
Lead Temperature (10 sec)
L
°C; derate to 300mW by 10mW/°C from 65°C to 85°C
-0.5 to +7 V
V
V
± 20 mA
± 20 mA
± 25 mA
± 50 mA
500(*) mW
-65 to +150 °C
300 °C
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M74HC161
RECOMMENDED OPERATING CONDITIONS
Symbol Parameter Value Unit
V
V
V
T
t
r
DC SPECIFICATIONS
Symbol Parameter
V
IH
V
IL
V
OH
V
OL
I
I
I
CC
Supply Voltage
CC
Input Voltage 0 to V
I
Output Voltage 0 to V
O
Operating Temperature
op
Input Rise and Fall Time VCC = 2.0V
, t
f
V
V
CC
CC
= 4.5V
= 6.0V
Test Condition Value
= 25°C
T
A
Min. Typ. Max. Min. Max. Min. Max.
High Level Input
V
CC
(V)
2.0 1.5 1.5 1.5
Voltage
6.0 4.2 4.2 4.2
Low Level Input
2.0 0.5 0.5 0.5
Voltage
6.0 1.8 1.8 1.8
High Level Output
Voltage
Low Level Output
Voltage
Input Leakage
Current
Quiescent Supply
Current
2.0
4.5
6.0
4.5
6.0
2.0
4.5
6.0
4.5
6.0
6.0
6.0
IO=-20 µA
I
=-20 µA
O
I
=-20 µA
O
I
=-4.0 mA
O
I
=-5.2 mA
O
IO=20 µA
I
=20 µA
O
I
=20 µA
O
I
=4.0 mA
O
I
=5.2 mA
O
= VCC or GND
V
I
= VCC or GND
V
I
1.9 2.0 1.9 1.9
4.4 4.5 4.4 4.4
5.9 6.0 5.9 5.9
4.18 4.31 4.13 4.10
5.68 5.8 5.63 5.60
0.0 0.1 0.1 0.1
0.0 0.1 0.1 0.1
0.0 0.1 0.1 0.1
0.17 0.26 0.33 0.40
0.18 0.26 0.33 0.40
± 0.1 ± 1 ± 1 µA
44080µA
2 to 6 V
CC
CC
-55 to 125 °C
0 to 1000 ns
0 to 500 ns
0 to 400 ns
-40 to 85°C -55 to 125°C
V
V
Unit
V4.5 3.15 3.15 3.15
V4.5 1.35 1.35 1.35
V
V
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