Fairchild Semiconductor DM74ALS373WMX, DM74ALS373WM, DM74ALS373SJX, DM74ALS373SJ, DM74ALS373N Datasheet
© 2000 Fairchild Semiconductor Corporation DS006220 www.fairchildsemi.com
April 1984
Revised February 2000
DM74ALS373 Octal D-Type 3-STATE Transparent Latch
DM74ALS373
Octal D-Type 3-STATE Transparent Latch
General Description
These 8-bit register s feature totem-pole 3- STATE o utputs
designed specifically fo r driving highly-capacitive or relatively low-impedance loa ds. Th e hi gh -im ped ance 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 bu s-or ga nized sy stem w ith ou t n eed fo r interface or pull-up components. They are parti cularly attractive
for implementing buffer registers, I/O ports, bidirectional
bus drivers, and working registers.
The eight latches of the DM74ALS 373 are transparent Dtype latches. While the enable (G) is HIGH the Q outputs
will follow the data (D) inputs. When the enable is taken
LOW the output will be latched at the level of the data that
was set up.
A buffered output control input ca n be used to place the
eight outputs in either a normal l ogic state (HIGH or LOW
logic levels) or a high-impedance state. In the high-impedance state the outputs ne ither load nor dr ive the bus lines
significantly.
The output control does not affect the i nternal oper ation of
the latches. That is, the old data can be retained or new
data can be entered even while the outputs are OFF.
Features
■ Switching specifications at 50 pF
■ Switching specifications guaranteed over full tempera-
ture and V
CC
range
■ Advanced oxide-isolated, ion-implanted Schottky TTL
process
■ Functionally and pin for pin compatible with LS TTL
counterpart
■ Improved AC perfo rma nce ov er DM74LS373 at app roxi mately half the power
■ 3-STATE buffer-type outputs drive bus lines directly
Ordering Code:
Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering code.
Connection Diagram
Order Number Package Number Package Description
DM74ALS373WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74ALS373SJ M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74ALS373N N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
www.fairchildsemi.com 2
DM74ALS373
Function Table
L = LOW State
H = HIGH State
X = Don’t Care
Z = High Impedance State
Q
0
= Previous Condit ion of Q
Logic Diagram
Output Enable D Output
Control G Q
LHHH
LHLL
LLXQ
0
HXXZ
3 www.fairchildsemi.com
DM74ALS373
Absolute Maximum Ratings(Note 1)
Note 1: The “Absolute M aximu m R atin gs” are t hose valu es b eyo nd w hich
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 “Recommend ed O peratin g Cond itions” t able w ill defin e the condition s
for actual device operation.
Recommended Operating Conditions
Note 2: The (↓) arrow in dic ates the negative edge of the enable is used for ref erence.
Electrical Characteristics
over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C.
Supply Voltage 7V
Input Voltage 7V
Voltage Applied to Disabled Output 5.5V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range −65°C to +150°C
Typical θ
JA
N Package 57.0°C/W
M Package 76.0°C/W
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.5 5 5.5 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current −2.6 mA
I
OL
LOW Level Output Current 24 mA
t
W
Width of Enable Pulse, HIGH or LOW 10 ns
t
SU
Data Setup Time (Note 2) 10↓ ns
t
H
Data Hold Time (Note 2) 7↓ ns
T
A
Free Air Operating Temperatur e 0 70 °C
Symbol Parameter Conditions Min Typ Max Units
V
IK
Input Clamp Voltage VCC = 4.5V, II = −18 mA −1.5 V
V
OH
HIGH Level VCC = 4.5V IOH = −2.6 mA 2.4 3.3 V
Output Voltage VCC = 4.5V to 5.5V
VCC − 2V
IOH = −400 µA
V
OL
LOW Level
VCC = 4.5V IOL = 24 mA 0.35 0.5 V
Output Voltage
I
I
Input Current at Maximum VCC = 5.5V
0.1 mA
Input Voltage VIH = 7V
I
IH
HIGH Level Input Current VCC = 5.5V, VIH = 2.7V 20 µA
I
IL
LOW Level Input Current VCC = 5.5V, VIL = 0.4V −0.1 mA
I
O
Output Drive Current VCC = 5.5V VO = 2.25V −30 −112 mA
I
OZH
OFF-State Output Current VCC = 5.5V
20 µA
HIGH Level Voltage Applied VO = 2.7V
I
OZL
OFF-State Output Current VCC = 5.5V
−20 µA
LOW Level Voltage Applied VO = 0.4V
I
CC
Supply Current VCC = 5.5V Outputs HIGH 9 16 mA
Outputs OPEN Outputs LOW 16 25 mA
Outputs Disabled 17 27 mA
Loading...