NSC 74AC843

74AC843 # 74ACT843
9-Bit Transparent Latch
General Description
Features
The ’AC/’ACT843 bus interface latch is designed to eliminate the extra packages required to buffer existing latches
and provide extra data width for wider address/data paths.
The ’AC/’ACT843 is functionally and pin compatible with
AMD’s Am29843.
Y
Logic Symbols
Y
’ACT843 has TTL-compatible inputs
TRI-STATEÉ outputs for bus interfacing
Connection Diagram
Pin Assignment
for DIP and SOIC
TL/F/9800 – 1
IEEE/IEC
TL/F/9800 – 2
TL/F/9800 – 3
Pin Names
D0 – D8
O0 – O8
OE
LE
CLR
PRE
Description
Data Inputs
Data Outputs
Output Enable
Latch Enable
Clear
Preset
TRI-STATEÉ is a registered trademark of National Semiconductor Corporation
FACTTM is a trademark of National Semiconductor Corporation
C1995 National Semiconductor Corporation
TL/F/9800
RRD-B30M75/Printed in U. S. A.
74AC843 # 74ACT843 9-Bit Transparent Latch
April 1993
Functional Description
addition to the LE and OE pins, the ’AC/’ACT843 has a
Clear (CLR) pin and a Preset (PRE) pin. These pins are ideal
for parity bus interfacing in high performance systems.
When CLR is LOW, the outputs are LOW if OE is LOW.
When CLR is HIGH, data can be entered into the latch.
When PRE is LOW, the outputs are HIGH if OE is LOW.
Preset overrides CLR.
The ’AC/’ACT843 consists of nine D-type latches with
TRI-STATE outputs. The flip-flops appear transparent to the
data when Latch Enable (LE) is HIGH. This allows asynchronous operation, as the output transition follows the data
in transition. On the LE HIGH-to-LOW transition, the data
that meets the setup times is latched. Data appears on the
bus when the Output Enable (OE) is LOW. When OE is
HIGH, the bus output is in the high impedance state. In
Function Tables
Internal
Outputs
CLR
PRE
Inputs
OE
LE
D
Q
O
H
H
H
H
H
H
H
L
L
L
H
H
H
H
H
H
H
L
H
L
H
L
H
H
H
L
L
L
L
L
L
H
H
H
H
L
H
H
L
X
X
X
L
L
L
H
X
L
H
X
X
X
X
X
X
L
H
NC
L
H
NC
H
L
H
L
H
Z
Z
Z
L
H
NC
H
L
H
Z
Z
Function
High Z
High Z
Latched
Transparent
Transparent
Latched
Preset
Clear
Preset
Clear/High Z
Preset/High Z
H e HIGH Voltage Level
L e LOW Voltage Level
X e Immaterial
Z e High Impedance
NC e No Change
Logic Diagram
TL/F/9800 – 5
2
Absolute Maximum Ratings (Note 1)
Recommended Operating
Conditions
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage (VCC)
DC Input Diode Current (IIK)
VI e b0.5V
VI e VCC a 0.5V
DC Input Voltage (VI)
DC Output Diode Current (IOK)
VO e b0.5V
VO e VCC a 0.5V
DC Output Voltage (VO)
DC Output Source
or Sink Current (IO)
DC VCC or Ground Current
per Output Pin (ICC or IGND)
Storage Temperature (TSTG)
Junction Temperature (TJ)
PDIP
Supply Voltage (VCC)
’AC
’ACT
Input Voltage (VI)
b 0.5V to a 7.0V
b 20 mA
a 20 mA
2.0V to 6.0V
4.5V to 5.5V
0V to VCC
0V to VCC
Output Voltage (VO)
Operating Temperature (TA)
74AC/ACT
b 0.5V to VCC a 0.5V
b 40§ C to a 85§ C
Minimum Input Edge Rate (DV/Dt)
’AC Devices
VIN from 30% to 70% of VCC
VCC @ 3.3V, 4.5V, 5.5V
Minimum Input Edge Rate (DV/Dt)
’ACT Devices
VIN from 0.8V to 2.0V
VCC @ 4.5V, 5.5V
b 20 mA
a 20 mA
b 0.5V to VCC a 0.5V
g 50 mA
g 50 mA
125 mV/ns
125 mV/ns
b 65§ C to a 150§ C
140§ C
Note 1: Absolute maximum ratings are those values beyond which damage
to the device may occur. The databook specifications should be met, without
exception, to ensure that the system design is reliable over its power supply,
temperature, and output/input loading variables. National does not recommend operation of FACT TM circuits outside databook specifications.
DC Electrical Characteristics for ’AC Family Devices
Symbol
Parameter
VCC
(V)
74AC
74AC
TA e a 25§ C
TA e
b 40§ C to a 85§ C
Typ
VIH
VIL
VOH
IIN
Conditions
Guaranteed Limits
Minimum High Level
Input Voltage
3.0
4.5
5.5
1.5
2.25
2.75
2.1
3.15
3.85
2.1
3.15
3.85
V
VOUT e 0.1V
or VCC b 0.1V
Maximum Low Level
Input Voltage
3.0
4.5
5.5
1.5
2.25
2.75
0.9
1.35
1.65
0.9
1.35
1.65
V
VOUT e 0.1V
or VCC b 0.1V
Minimum High Level
Output Voltage
3.0
4.5
5.5
2.99
4.49
5.49
2.9
4.4
5.4
2.9
4.4
5.4
V
2.56
3.86
4.86
2.46
3.76
4.76
V
0.1
0.1
0.1
0.1
0.1
0.1
V
3.0
4.5
5.5
0.36
0.36
0.36
0.44
0.44
0.44
V
5.5
g 0.1
g 1.0
mA
3.0
4.5
5.5
VOL
Units
Maximum Low Level
Output Voltage
Maximum Input
Leakage Current
3.0
4.5
5.5
0.002
0.001
0.001
*All outputs loaded; thresholds on input associated with output under test.
3
IOUT e b50 mA
*VIN e VIL or VIH
b 12 mA
b 24 mA
IOH
b 24 mA
IOUT e 50 mA
*VIN e VIL or VIH
12 mA
24 mA
IOL
24 mA
VI e VCC, GND
DC Electrical Characteristics for ’AC Family Devices (Continued)
Symbol
Parameter
VCC
(V)
74AC
74AC
TA e a 25§ C
TA e
b 40§ C to a 85§ C
Units
Conditions
g 5.0
mA
VI (OE) e VIL, VIH
VI e VCC, GND
VO e VCC, GND
5.5
75
mA
VOLD e 1.65V Max
5.5
b 75
mA
VOHD e 3.85V Min
80.0
mA
VIN e VCC
or GND
Typ
IOZ
IOLD
IOHD
ICC
Maximum TRI-STATE
Leakage Current
² Minimum Dynamic
Output Current
Maximum Quiescent
Supply Current
Guaranteed Limits
5.5
g 0.5
5.5
8.0
² Maximum test duration 2.0 ms, one output loaded at a time.
Note: IIN and ICC
@
3.0V are guaranteed to be less than or equal to the respective limit
@
5.5V VCC.
DC Electrical Characteristics for ’ACT Family Devices
Symbol
Parameter
VCC
(V)
74ACT
74ACT
TA e a 25§ C
TA e
b 40§ C to a 85§ C
Typ
Units
Conditions
Guaranteed Limits
VIH
Minimum High Level
Input Voltage
4.5
5.5
1.5
1.5
2.0
2.0
2.0
2.0
V
VOUT e 0.1V
or VCC b 0.1V
VIL
Maximum Low Level
Input Voltage
4.5
5.5
1.5
1.5
0.8
0.8
0.8
0.8
V
VOUT e 0.1V
or VCC b 0.1V
VOH
Minimum High Level
Output Voltage
4.5
5.5
4.49
5.49
4.4
5.4
4.4
5.4
V
3.86
4.86
3.76
4.76
V
0.1
0.1
0.1
0.1
V
4.5
5.5
0.36
0.36
0.44
0.44
V
4.5
5.5
VOL
Maximum Low Level
Output Voltage
4.5
5.5
0.001
0.001
IIN
Maximum Input
Leakage Current
5.5
g 0.1
g 1.0
mA
IOZ
Maximum TRI-STATE
Leakage Current
5.5
g 0.5
g 5.0
mA
ICCT
Maximum
ICC/Input
5.5
1.5
mA
IOLD
² Minimum Dynamic
Output Current
IOHD
ICC
Maximum Quiescent
Supply Current
0.6
IOUT e b50 mA
*VIN e VIL or VIH
b 24 mA
IOH
b 24 mA
IOUT e 50 mA
*VIN e VIL or VIH
24 mA
IOL
24 mA
VI e VCC, GND
VI e VIL, VIH
VO e VCC, GND
VI e VCC b 2.1V
5.5
75
mA
VOLD e 1.65V Max
5.5
b 75
mA
VOHD e 3.85V Min
80.0
mA
VIN e VCC
or GND
5.5
8.0
*All outputs loaded; thresholds on input associated with output under test.
² Maximum test duration 2.0 ms, one output loaded at a time.
4
AC Electrical Characteristics
Symbol
Parameter
VCC*
(V)
74AC
74AC
TA e a 25§ C
CL e 50 pF
TA e b40§ C
to a 85§ C
CL e 50 pF
Units
Min
Typ
Max
Min
Max
tPLH
Propagation Delay
Dn to On
3.3
5.0
3.5
2.0
6.5
4.5
12.0
8.5
2.5
1.5
13.0
9.0
ns
tPHL
Propagation Delay
Dn to On
3.3
5.0
4.0
2.5
7.0
5.0
12.0
8.5
3.0
1.5
13.0
9.0
ns
tPLH
Propagation Delay
LE to On
3.3
5.0
3.5
2.0
6.5
4.5
12.0
8.5
13.0
1.5
2.5
9.0
ns
tPHL
Propagation Delay
LE to On
3.3
5.0
4.0
2.5
7.0
5.0
12.0
8.5
3.0
1.5
13.0
9.0
ns
tPLH
Propagation Delay
PRE to On
3.3
5.0
5.5
3.5
8.5
6.0
19.0
13.0
4.5
2.5
21.5
14.5
ns
tPHL
Propagation Delay
CLR to On
3.3
5.0
7.5
5.0
11.0
7.5
21.5
15.0
6.0
4.0
24.0
17.0
ns
tPZH
Output Enable Time
OE to On
3.3
5.0
3.5
2.0
6.0
4.5
11.0
8.0
3.0
1.5
12.0
9.0
ns
tPZL
Output Enable Time
OE to On
3.3
5.0
4.0
2.0
6.5
5.0
11.0
8.0
2.5
1.5
12.0
9.0
ns
tPHZ
Output Disable Time
OE to On
3.3
5.0
4.0
3.0
6.5
5.0
10.5
8.0
3.5
2.5
11.0
8.5
ns
tPLZ
Output Disable Time
OE to On
3.3
5.0
3.0
2.0
6.0
4.5
10.5
8.0
2.5
1.5
11.0
8.5
ns
tPHL
Propagation Delay
PRE to On
3.3
5.0
4.5
3.0
7.0
5.0
12.5
9.0
3.5
2.0
13.5
9.5
ns
tPLH
Propagation Delay
CLR to On
3.3
5.0
4.5
3.0
7.0
5.0
12.5
9.0
3.5
2.0
13.5
9.5
ns
*Voltage Range 3.3 is 3.3V g 0.3V
*Voltage Range 5.0 is 5.0V g 0.5V
5
AC Operating Requirements
74AC
74AC
TA e a 25§ C
CL e 50 pF
TA e b40§ C
to a 85§ C
CL e 50 pF
Parameter
VCC*
(V)
ts
Setup Time, HIGH or LOW
Dn to LE
3.3
5.0
0
b 0.5
3.0
1.5
3.5
2.0
ns
th
Hold Time, HIGH or LOW
Dn to LE
3.3
5.0
b 0.5
2.0
2.5
2.0
2.5
ns
tw
LE Pulse Width, HIGH
3.3
5.0
1.5
1.5
3.0
3.0
3.0
3.0
ns
tw
PRE Pulse Width, LOW
3.3
5.0
5.0
3.0
12.0
8.5
14.5
10.0
ns
tw
CLR Pulse Width, LOW
3.3
5.0
5.5
4.0
14.0
10.0
16.5
12.0
ns
trec
PRE Recovery Time
3.3
5.0
1.0
0
3.0
1.5
3.0
1.5
ns
trec
CLR Recovery Time
3.3
5.0
0
b 0.5
1.5
0.5
1.5
0.5
ns
Symbol
Typ
*Voltage Range 3.3 is 3.3V g 0.3V
*Voltage Range 5.0 is 5.0V g 0.5V
6
Units
Guaranteed Minimum
AC Electrical Characteristics
Symbol
Parameter
VCC*
(V)
74ACT
74ACT
TA e a 25§ C
CL e 50 pF
TA e b40§ C
to a 85§ C
CL e 50 pF
Units
Min
Typ
Max
Min
Max
5.0
2.5
5.5
9.5
2.0
10.0
ns
Propagation Delay
Dn to On
5.0
2.5
5.5
9.5
2.0
10.0
ns
tPLH
Propagation Delay
LE to On
5.0
2.5
5.5
9.0
2.0
10.0
ns
tPHL
Propagation Delay
LE to On
5.0
2.5
5.5
9.0
2.0
10.0
ns
tPLH
Propagation Delay
PRE to On
5.0
2.5
6.5
14.0
2.0
16.0
ns
tPHL
Propagation Delay
CLR to On
5.0
2.5
7.5
15.5
2.0
17.5
ns
tPZH
Output Enable Time
OE to On
5.0
2.5
5.5
9.5
2.0
10.5
ns
tPZL
Output Enable Time
OE to On
5.0
2.5
5.5
9.5
2.0
10.5
ns
tPHZ
Output Disable Time
OE to On
5.0
2.5
6.0
10.5
2.0
11.0
ns
tPLZ
Output Disable Time
OE to On
5.0
2.5
6.0
10.5
2.0
11.0
ns
tPHL
Propagation Delay
PRE to On
5.0
2.5
6.0
10.5
2.0
11.0
ns
tPLH
Propagation Delay
CLR to On
5.0
2.5
5.5
9.5
2.0
10.5
ns
tPLH
Propagation Delay
Dn to On
tPHL
*Voltage Range 5.0 is 5.0V g 0.5V
AC Operating Requirements
Symbol
Parameter
VCC*
(V)
Typ
74AC
74AC
TA e a 25§ C
CL e 50 pF
TA e b40§ C
to a 85§ C
CL e 50 pF
Units
Guaranteed Minimum
ts
Setup Time, HIGH or LOW
Dn to LE
5.0
b 0.5
0.5
1.0
ns
th
Hold Time, HIGH or LOW
Dn to LE
5.0
0.5
2.0
2.0
ns
tw
LE Pulse Width, HIGH
5.0
2.0
3.5
3.5
ns
tw
PRE Pulse Width, LOW
5.0
5.0
8.5
10.0
ns
tw
CLR Pulse Width, LOW
5.0
5.5
9.5
11.0
ns
trec
PRE Recovery Time
5.0
0.5
2.0
2.0
ns
trec
CLR Recovery Time
5.0
b 0.5
1.0
1.0
ns
*Voltage Range 5.0 is 5.0V g 0.5V
7
Capacitance
Typ
Units
Conditions
CIN
Symbol
Input Capacitance
Parameter
4.5
pF
VCC e OPEN
CPD
Power Dissipation Capacitance
44
pF
VCC e 5.0V
Ordering Information
The device number is used to form part of a simplified purchasing code where a package type and temperature range are
defined as follows:
74AC
843
P
Temperature Range Family
74AC e Commercial
74ACT e Commercial TTL-Compatible
C
QR
Special Variations
X e Devices shipped in
13× reels
QR e Commercial grade device
with burn-in
Device Type
Package Code
SP e Slim Plastic DIP
S e Small Outline (SOIC)
Temperature Range
C e Commercial (b40§ C to a 85§ C)
8
Physical Dimensions inches (millimeters)
24-Lead Small Outline Integrated Circuit (S)
NS Package Number M24B
9
74AC843 # 74ACT843 9-Bit Transparent Latch
Physical Dimensions inches (millimeters) (Continued)
Lit. Ý 114638
24-Lead Slim (0.300× Wide) Plastic Dual-In-Line Package (SP)
NS Package Number N24C
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL
SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and whose
failure to perform, when properly used in accordance
with instructions for use provided in the labeling, can
be reasonably expected to result in a significant injury
to the user.
National Semiconductor
Corporation
2900 Semiconductor Drive
P.O. Box 58090
Santa Clara, CA 95052-8090
Tel: 1(800) 272-9959
TWX: (910) 339-9240
National Semiconductor
GmbH
Livry-Gargan-Str. 10
D-82256 F4urstenfeldbruck
Germany
Tel: (81-41) 35-0
Telex: 527649
Fax: (81-41) 35-1
National Semiconductor
Japan Ltd.
Sumitomo Chemical
Engineering Center
Bldg. 7F
1-7-1, Nakase, Mihama-Ku
Chiba-City,
Ciba Prefecture 261
Tel: (043) 299-2300
Fax: (043) 299-2500
2. A critical component is any component of a life
support device or system whose failure to perform can
be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or
effectiveness.
National Semiconductor
Hong Kong Ltd.
13th Floor, Straight Block,
Ocean Centre, 5 Canton Rd.
Tsimshatsui, Kowloon
Hong Kong
Tel: (852) 2737-1600
Fax: (852) 2736-9960
National Semiconductores
Do Brazil Ltda.
Rue Deputado Lacorda Franco
120-3A
Sao Paulo-SP
Brazil 05418-000
Tel: (55-11) 212-5066
Telex: 391-1131931 NSBR BR
Fax: (55-11) 212-1181
National Semiconductor
(Australia) Pty, Ltd.
Building 16
Business Park Drive
Monash Business Park
Nottinghill, Melbourne
Victoria 3168 Australia
Tel: (3) 558-9999
Fax: (3) 558-9998
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.