5-1
FAST AND LS TTL DATA
SERIAL-IN PARALLEL-OUT
SHIFT REGISTER
The SN54/74LS164 is a high speed 8-Bit Serial-In Parallel-Out Shift Regis-
ter. Serial data is entered through a 2-Input AND gate synchronous with the
LOW to HIGH transition of the clock. The device features an asynchronous
Master Reset which clears the register setting all outputs LOW independent of
the clock. It utilizes the Schottky diode clamped process to achieve high
speeds and is fully compatible with all Motorola TTL products.
•Typical Shift Frequency of 35 MHz
•Asynchronous Master Reset
•Gated Serial Data Input
•Fully Synchronous Data Transfers
•Input Clamp Diodes Limit High Speed Termination Effects
•ESD > 3500 Volts
CONNECTION DIAGRAM DIP (TOP VIEW)
14 13 12 11 10 9
123456
8
7
VCC Q7Q6Q5Q4MR CP
A B Q0Q1Q2Q3GND
NOTE:
The Flatpak version
has the same pinouts
(Connection Diagram) as
the Dual In-Line Package.
PIN NAMES LOADING (Note a)
HIGH LOW
A, B
CP
MR
Q0–Q7
Data Inputs
Clock (Active HIGH Going Edge) Input
Master Reset (Active LOW) Input
Outputs (Note b)
0.5 U.L.
0.5 U.L.
0.5 U.L.
10 U.L.
0.25 U.L.
0.25 U.L.
0.25 U.L.
5 (2.5) U.L.
NOTES:
a) 1 TTL Unit Load (U.L.) = 40 µA HIGH/1.6 mA LOW.
b) The Output LOW drive factor is 2.5 U.L. for Military (54) and 5 U.L. for Commercial (74)
Temperature Ranges.
SN54/74LS164
SERIAL-IN PARALLEL-OUT
SHIFT REGISTER
LOW POWER SCHOTTKY
J SUFFIX
CERAMIC
CASE 632-08
N SUFFIX
PLASTIC
CASE 646-06
14 1
14
1
ORDERING INFORMATION
SN54LSXXXJ Ceramic
SN74LSXXXN Plastic
SN74LSXXXD SOIC
14 1
D SUFFIX
SOIC
CASE 751A-02
LOGIC SYMBOL
1
2
8
9 3 4 5 6 10 11 12 13
A
B
CP
LS164
8-BIT SHIFT REGISTER
MR Q0Q1Q2Q3Q4Q5Q6Q7
VCC = PIN 14
GND = PIN 7
5-2
FAST AND LS TTL DATA
SN54/74LS164
LOGIC DIAGRAM
Q6Q7
A
B
Q0Q1Q3
Q2Q5
Q4
MR
CP
D Q
CD
D Q
CD
D Q
CD
D Q
CD
D Q
CD
D Q
CD
D Q
CD
D Q
CD
63 4 5 11 1210 13
VCC = PIN 14
GND = PIN 7
= PIN NUMBERS
1
2
8
9
FUNCTIONAL DESCRIPTION
The LS164 is an edge-triggered 8-bit shift register with seri-
al data entry and an output from each of the eight stages. Data
is entered serially through one of two inputs (A or B); either of
these inputs can be used as an active HIGH Enable for data
entry through the other input. An unused input must be tied
HIGH, or both inputs connected together.
Each LOW-to-HIGH transition on the Clock (CP) input shifts
data one place to the right and enters into Q0 the logical AND
of the two data inputs (A•B) that existed before the rising clock
edge. A LOW level on the Master Reset (MR) input overrides
all other inputs and clears the register asynchronously , forcing
all Q outputs LOW.
MODE SELECT — TRUTH TABLE
OPERATING
MODE
INPUTS OUTPUTS
MODE
MR A B Q0Q1–Q7
Reset (Clear) L X X L L – L
H I I L q0– q6
Shift H I h L q0– q6
H h I L q0– q6
H h h H q0– q6
L (l) = LOW Voltage Levels
H (h) = HIGH Voltage Levels
X = Don’t Care
qn = Lower case letters indicate the state of the referenced input or output one
qn = set-up time prior to the LOW to HIGH clock transition.
GUARANTEED OPERATING RANGES
Symbol Parameter Min Typ Max Unit
VCC Supply Voltage 54
74 4.5
4.75 5.0
5.0 5.5
5.25 V
TAOperating Ambient Temperature Range 54
74 –55
025
25 125
70 °C
IOH Output Current — High 54, 74 –0.4 mA
IOL Output Current — Low 54
74 4.0
8.0 mA
5-3
FAST AND LS TTL DATA
SN54/74LS164
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)
Symbol
Parameter
Limits
Unit
Test Conditions
Symbol
Parameter
Min Typ Max
Unit
Test Conditions
VIH Input HIGH Voltage 2.0 V Guaranteed Input HIGH Voltage for
All Inputs
VIL
Input LOW Voltage
54 0.7
V
Guaranteed Input LOW Voltage for
All Inputs
VIL
Input LOW Voltage
74 0.8
V
Guaranteed Input LOW Voltage for
All Inputs
VIK Input Clamp Diode Voltage –0.65 –1.5 V VCC = MIN, IIN = –18 mA
VOH
Output HIGH Voltage
54 2.5 3.5
V
V
CC = MIN, IOH = MAX, VIN = VIH
or VIL per Truth Table
VOH
Output HIGH Voltage
74 2.7 3.5
V
VCC = MIN, IOH = MAX, VIN = VIH
or VIL per Truth Table
VOL
Output LOW Voltage
54, 74 0.25 0.4 V IOL = 4.0 mA
VCC = VCC MIN,
VIN = VIH or VIL
per Truth Table
VOL
Output LOW Voltage
74 0.35 0.5 V IOL = 8.0 mA
VIN = VIH or VIL
per Truth Table
IIH
Input HIGH Current
20 µA VCC = MAX, VIN = 2.7 V
IIH
Input HIGH Current
0.1 mA VCC = MAX, VIN = 7.0 V
IIL Input LOW Current –0.4 mA VCC = MAX, VIN = 0.4 V
IOS Short Circuit Current (Note 1) –20 –100 mA VCC = MAX
ICC Power Supply Current 27 mA VCC = MAX
Note 1: Not more than one output should be shorted at a time, nor for more than 1 second.
AC CHARACTERISTICS (TA = 25°C)
Symbol
Parameter
Limits
Unit
Test Conditions
Symbol
Parameter
Min Typ Max
Unit
Test Conditions
fMAX Maximum Clock Frequency 25 36 MHz
VCC = 5.0 V
CL = 15 pF
tPHL Propagation Delay
MR to Output Q 24 36 ns
VCC = 5.0 V
CL = 15 pF
tPLH
tPHL Propagation Delay
Clock to Output Q 17
21 27
32 ns
CL = 15 pF
AC SETUP REQUIREMENTS (TA = 25°C)
Symbol
Parameter
Limits
Unit
Test Conditions
Symbol
Parameter
Min Typ Max
Unit
Test Conditions
tWCP, MR Pulse Width 20 ns
VCC = 5.0 V
tsData Setup Time 15 ns
VCC = 5.0 V
thData Hold Time 5.0 ns
VCC = 5.0 V
trec MR to Clock Recovery Time 20 ns
5-4
FAST AND LS TTL DATA
SN54/74LS164
AC WAVEFORMS
*The shaded areas indicate when the input is permitted to change for predictable output performance.
Figure 1. Clock to Output Delays
and Clock Pulse Width Figure 2. Master Reset Pulse Width,
Master Reset to Output Delay and
Master Reset to Clock Recovery Time
Figure 3. Data Setup and Hold Times
CONDITIONS: MR = H
1.3 V
1.3 V 1.3 V 1.3 V
1.3 V
1.3 V 1.3 V
1.3 V
1.3 V
tPHL tPLH
CP
QCP
Q
MR
trec
tW
tPHL
tW
I/fmax
1.3 V
1.3 V 1.3 V
1.3 V 1.3 V 1.3 V 1.3 V
CP
D
Q
ts(H) th(H) ts(L) th(L)
tW
1/fmax
1.3 V 1.3 V* 1.3V
