4-150
FAST AND LS TTL DATA
8-INPUT SHIFT/STORAGE
REGISTER WITH SYNCHRONOUS
RESET AND COMMON I/O PINS
The MC74F323 is an 8-Bit Universal Shift/Storage Register with 3-state
outputs. Its function is similar to the F299 with the exception of Synchronous
Reset.
The parallel load inputs and flip-flop outputs are multiplexed to reduce the
total number of package pins. Separate outputs are provided for flip-flops Q0
and Q7 to allow easy cascading. A separate active LOW Master Reset is used
to reset the register.
Four modes of operation are possible: hold (store), shift left, shift right and
parallel load. All modes are activated on the LOW-to-HIGH transition of the
clock.
•
Common I/O For Reduced Pin Count
•
Four Operation Modes: Shift Left, Shift Right, Parallel Load and Store
•
Separate Continuous Inputs and Outputs from Q0 and Q7 Allow Easy
Cascading
•
Fully Synchronous Reset
•
3-State Outputs for Bus Oriented Applications
•
Input Clamp Diodes Limit High-Speed Termination Effects
CONNECTION DIAGRAM
18
17
16
15
14
13
1
2
3
4
5
6
7
20
19
8
VCC
S0
S1 DS7 Q7 I/O7
I/O3
I/O5
I/O1
OE1 OE2 I/O6 I/O4 I/O2 I/O0 Q0
9
10
SR
GND
12
11
CP
DS0
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
VCC
Supply Voltage
74
4.5
5.0
5.5
V
TA
Operating Ambient Temperature Range
74
0
25
70
°
C
IOH
Output Current — High
74
–1.0/– 3.0
mA
IOL
Output Current — Low
74
20/24
mA
MC74F323
8-INPUT SHIFT/STORAGE
REGISTER WITH SYNCHRONOUS
RESET AND COMMON I/O PINS
FAST
™
SCHOTTKY TTL
ORDERING INFORMATION
MC74FXXXJ
Ceramic
MC74FXXXN
Plastic
MC74FXXXDW SOIC
20
1
J SUFFIX
CERAMIC
CASE 732-03
20
1
N SUFFIX
PLASTIC
CASE 738-03
20
1
DW SUFFIX
SOIC
CASE 751D-03
4-151
FAST AND LS TTL DATA
MC74F323
FUNCTION TABLE
Inputs
SR
S1
S0
CP
Response
L
X
X
↑
Synchronous Reset: Q0–Q7 = LOW
H
H
H
↑
Parallel Load: I/On Qn
H
L
H
↑
Shift Right: DS0 Q0, Q0 Q1, etc.
H
H
L
↑
Shift Left: DS7 Q7, Q7 Q6, etc.
H
L
L
X
Hold
H = HIGH Voltage Level
L = LOW Voltage Level
X = Don’t Care
↑
= LOW-to-HIGH clock transition.
FUNCTIONAL DESCRIPTION
The MC74F323 contains eight edge-triggered D-type
flips-flops and the interstage logic necessary to perform
synchronous reset, shift left, shift right, parallel load and hold
operations. The type of operation is determined by S0 and S1,
as shown in the Function Table. All flip-flop outputs are
brought out through 3-state buffers to separate I/O pins that
also serve as data inputs in the parallel load mode. Q0 and Q7
are also brought out on other pins for expansion in serial
shifting of longer words.
A LOW signal on SR overrides the Select inputs and allows
the flip-flops to be reset by the next rising edge of CP. All other
state changes are initiated by the LOW-to-HIGH CP transition.
Inputs can change when the clock is in either state provided
only that the recommended set-up and hold times, relative to
the rising edge of CP, are observed.
A HIGH signal on either OE1 or OE2 disables the 3-state
buffers and puts the I/O pins in the high impedance state. In
this condition the shift, hold, load and reset operations can still
occur. The 3-state buffers are also disabled by HIGH signals
on both S0 and S1 in preparation for a parallel load operation.
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
VIL
Input LOW Voltage
0.8
V
Guaranteed Input LOW Voltage
VIK
Input Clamp Diode Voltage
–1.2
V
VCC = MIN, IIN = –18 mA
VOH
Output HIGH Voltage
Q0/Q7
74
2.5
V
IOH = –1.0 mA
VCC = 4.5 V
VOH
Output HIGH Voltage
Q0/Q7
74
2.7
V
IOH = –1.0 mA
VCC = 4.75 V
VOH
Output HIGH Voltage
I/O
74
2.7
3.4
V
IOH = – 3.0 mA
VCC = 4.75 V
I/O
74
2.4
V
IOH = – 3.0 mA
VCC = 4.5 V
VOL
Output LOW Voltage
Q0/Q7
0.5
V
IOL = 20 mA
VCC = MIN
VOL
Output LOW Voltage
I/O
0.5
V
IOL = 24 mA
VCC = MIN
IIH
Input HIGH Current
Q0/Q7
20
µ
A
VCC = MAX, VIN = 2.7 V
IIH
Input HIGH Current
I/O
70
µ
A
VCC = MAX, VIN = 2.7 V
IIH
Input HIGH Current
Q0/Q7
0.1
mA
VCC = MAX
VIN = 7.0 V
I/O
1.0
mA
VCC = MAX
VIN = 5.5 V
IIL
Input LOW Current
S0, S1
–1.2
mA
VCC = MAX, VIN = 0.5 V
IIL
Input LOW Current
Other Inputs
– 0.6
mA
VCC = MAX, VIN = 0.5 V
IOZH
Off-State Output Current,
70
µ
A
VCC = MAX
VOUT = 2.7 V
IOZH
Off-State Output Current,
High-Level Voltage Applied
1.0
mA
VCC = MAX
VOUT = 5.5 V
IOZL
Off-State Output Current,
Low-Level Voltage Applied
– 0.6
mA
VCC = MAX, VOUT = 0.5 V
IOS
Output Short Circuit Current (Note 2)
– 60
–150
mA
VCC = MAX
VOUT = 0 V
ICC
Total Supply Current
95
mA
VCC = MAX
Outputs Disabled
NOTES:
1. For conditions shown as MIN or MAX, use appropriate value specified under recommended operating conditions for the applicable device type.
2. Not more than one output should be shorted at a time, nor for more than 1 second.
