74AC299B STMICROELECTRONICS [STMicroelectronics], 74AC299B Datasheet - Page 2

• Manufacturer Part Number: 74AC299B
• Description: 8 BIT PIPO SHIFT REGISTER WITH ASYNCHRONOUS CLEAR
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

74AC299
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
TRUTH TABLE
* When one or both controls are high, the eight input/output terminals are the high impedance state: howewer sequential operation or cleaning
Z : High Impedance
Qn0 : The level of An before the indicated steady state input conditions were established.
Qnn : The level of Qn before the most recent active transition indicated by OR
a, h : The level of the steadystate inputs A, H, respectively.
X : Don’t Care
2/13
of the register is not affected.
7, 13, 6, 14, 5, 15, 4, 16
CLEAR
RIGHT
MODE
SHIFT
SHIFT
HOLD
LOAD
LEFT
Z
PIN No
1, 19
8, 17
CLEAR
2, 3
12
18
10
20
11
9
H
H
H
H
H
H
L
L
L
SELECTED
S1
FUNCTION
H
H
H
H
X
L
L
L
L
S0
H
H
H
H
X
L
L
L
L
A/QA to H/QH
INPUTS
QA’ to QH’
SYMBOL
CLOCK
CLEAR
G1, G2
S0, S1
GND
V
SR
SL
CC
G1*
CONTROL
X
X
L
L
L
L
L
L
L
OUTPUT
G2*
X
X
L
L
L
L
L
L
L
Mode Select Inputs
3-State Output Enable Inputs (Active LOW)
Parallel Data Inputs or 3-State Parallel Outputs (Bus Driver)
Serial Outputs (Standard Output)
Asynchronous Master Reset Input (Active LOW)
Serial Data Shift Right Input
Clock Input (LOW to HIGH, Edge-triggered)
Serial Data Shift Left Input
Ground (0V)
Positive Supply Voltage
CLOCK
X
X
X
X
SL
H
X
X
X
X
X
X
X
L
SERIAL
NAME AND FUNCTION
INPUTS/OUTPUTS
SR
X
X
X
X
H
X
X
X
L
A/QA
QA0
QBn
QBn
Z
H
L
L
L
a
H/QH
QH0
QGn
QGn
H
Z
L
L
L
h
QA0
QBn
QBn
QA’
OUTPUTS
H
L
L
L
L
a
QGn
QGn
QH0
QH’
H
L
L
L
L
h