Fairchild DM74AS374N Octal d-type edge-triggered flip-flop Datasheet

Revised March 2000
DM74AS374
Octal D-Type Edge-Triggered Flip-Flops
with 3-STATE Outputs
General Description
Features
These 8-bit registers feature totem-pole 3-STATE outputs
designed specifically for driving highly-capacitive or relatively low-impedance loads. The high-impedance state and
increased high-logic-level drive provide these registers with
the capability of being connected directly to and driving the
bus lines in a bus-organized system without need for interface or pull-up components. They are particularly attractive
for implementing buffer registers, I/O ports, bidirectional
bus drivers, and working registers.
■ Switching specifications at 50 pF
The eight flip-flops of the AS374 are edge-triggered D-type
flip-flops. On the positive transition of the clock, the Q outputs will be set to the logic states that were set up at the D
inputs.
■ Switching specifications guaranteed over full temperature and VCC range
■ Advanced oxide-isolated, ion-implanted Schottky TTL
process
■ Functionally and pin-for-pin compatible with LS and ALS
TTL counterparts
■ Improved AC performance over LS and ALS TTL counterparts
■ 3-STATE buffer-type outputs drive bus lines directly
A buffered output control input can be used to place the
eight outputs in either a normal logic state (HIGH or LOW
logic levels) or a high impedance state. In the high-impedance state the outputs neither load nor drive the bus lines
significantly.
The output control does not affect the internal operation of
the flip-flops. That is, the old data can be retained or new
data can be entered even while the outputs are off.
Ordering Code:
Order Number
Package Number
DM74AS374WM
M20B
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Package Description
DM74AS374N
N20A
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram
© 2000 Fairchild Semiconductor Corporation
DS006310
www.fairchildsemi.com
DM74AS374 Octal D-Type Edge-Triggered Flip-Flops with 3-STATE Outputs
October 1986
DM74AS374
Function Table
Output
Logic Diagram
Clock
D
L
↑
H
L
↑
L
L
L
L
X
Q0
H
X
X
Z
Control
Output
Q
H
L = LOW State
H = HIGH State
X = Don’t Care
↑ = Positive Edge Transition
Z = High Impedance State
Q0 = Previous Condition of Q
www.fairchildsemi.com
2
DM74AS374
Absolute Maximum Ratings(Note 1)
Supply Voltage
7V
Input Voltage
7V
Voltage Applied to Disabled Output
5.5V
0°C to +70°C
Operating Free Air Temperature Range
−65°C to +150°C
Storage Temperature Range
Note 1: The “Absolute Maximum Ratings” are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
Typical θJA
N Package
52.5°C/W
M Package
70.5°C/W
Recommended Operating Conditions
Symbol
Parameter
Min
Nom
Max
Units
4.5
5
5.5
V
Low Level Input Voltage
0.8
V
VCC
Supply Voltage
VIH
High Level Input Voltage
VIL
2
V
IOH
High Level Output Current
−15
mA
IOL
Low Level Output Current
48
mA
fCLK
Clock Frequency
125
MHz
tW
Width of Clock Pulse
0
HIGH
4
LOW
3
ns
tSU
Data Setup Time (Note 2)
2↑
0
tH
Data Hold Time (Note 2)
3↑
0
TA
Operating Free Air Temperature
0
ns
ns
°C
70
Note 2: The (↑) arrow indicates the positive edge of the Clock is used for reference.
Electrical Characteristics
over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C.
Symbol
Parameter
Conditions
VIK
Input Clamp Voltage
VCC = 4.5V, II = −18 mA
VOH
HIGH Level
VCC = 4.5V, IOH = Max
Output Voltage
IOH = −2 mA, VCC = 4.5V to 5.5V
VOL
LOW Level
Output Voltage
Min
2.4
Input Current @ Max Input Voltage
VCC = 5.5V, VIH = 7V
Max
Units
−1.2
V
3.2
V
VCC − 2
VCC = 4.5V, IOL = Max
II
Typ
0.35
0.5
V
0.1
mA
IIH
HIGH Level Input Current
VCC = 5.5V, VIH = 2.7V
20
µA
IIL
LOW Level Input Current
VCC = 5.5V, VIL = 0.4V
−0.5
mA
IO
Output Drive Current
VCC = 5.5V, VO = 2.25V
−112
mA
IOZH
OFF-State Output Current,
VCC = 5.5V, VO = 2.7V
50
µA
VCC = 5.5V, VO = 0.4V
−50
µA
−30
HIGH Level Voltage Applied
IOZL
OFF-State Output Current,
LOW Level Voltage Applied
ICC
Supply Current
VCC = 5.5V
Outputs HIGH
77
Outputs Open
Outputs LOW
84
128
Outputs Disabled
84
128
3
120
mA
www.fairchildsemi.com
DM74AS374
Switching Characteristics
over recommended operating free air temperature range
Symbol
Parameter
Conditions
fMAX
Maximum Clock Frequency
VCC = 4.5V to 5.5V
tPLH
Propagation Delay Time
RL = 500Ω
LOW-to-HIGH Level Output
CL = 50 pF
tPHL
From
Propagation Delay Time
Output Enable Time
to HIGH Level Output
tPZL
Output Enable Time
to LOW Level Output
tPHZ
Output Disable Time
from HIGH Level Output
tPLZ
Output Disable Time
from LOW Level Output
www.fairchildsemi.com
Min
Max
125
HIGH-to-LOW Level Output
tPZH
To
4
Units
MHz
Clock
Any Q
3
8
ns
Clock
Any Q
4
9
ns
Output Control
Any Q
2
6
ns
Output Control
Any Q
3
10
ns
Output Control
Any Q
2
6
ns
Output Control
Any Q
2
6
ns
DM74AS374
Physical Dimensions inches (millimeters) unless otherwise noted
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Package Number M20B
5
www.fairchildsemi.com
DM74AS374 Octal D-Type Edge-Triggered Flip-Flops with 3-STATE Outputs
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Package Number N20A
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
LIFE SUPPORT POLICY
FAIRCHILD’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 FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in 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.
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 (c) 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.
www.fairchildsemi.com
www.fairchildsemi.com
6
Similar pages