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74ABT273
Octal D-Type Flip-Flop
74ABT273 Octal D-Type Flip-Flop
January 1993
Revised November 1999
General Description
The ABT273 has eight edge-triggered D-type flip-flops with
individual D inputs and Q outp uts. The common buffered
Clock (CP) and Master Reset (MR
(clear) all flip-flops simultaneously.
The register is fully edge-t riggered. The state of each D
input, one setup time before the LOW-to-HIGH clock transition, is transferred to the corresponding flip-flop’s Q output.
All outputs will be forced LOW indepe ndently of Clock or
Data inputs by a LOW voltage level on the MR
device is useful for a pplic ations where the true outpu t only
is required and the Clock and Master Reset are common to
all storage elements.
) inputs load and reset
input. The
Features
■ Eight edge-triggered D-typ e flip-fl o ps
■ Buffered common clock
■ Buffered, asynchronous Master Reset
■ See ABT377 for clock enable version
■ See ABT373 for transparent latch version
■ See ABT374 for 3-STATE version
■ Output sink capability of 64 mA, source capability of
32 mA
■ Guaranteed latchup protection
■ High impedance glitch free bus loading during entire
power up and power down cycle
■ Non-destructive hot insertion capability
■ Disable time less than ena ble time to avoi d bus conten-
tion
Ordering Code:
Order Number Package Number Package Description
74ABT273CSC M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300” Wide Body
74ABT273CSJ M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
74ABT273CMSA MSA20 20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide
74ABT273CMTC MTC20 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering co de.
Connection Diagram Pin Descriptions
Pin Names Description
D
0–D7
MR
CP Clock Pulse Input (Active Rising Edge)
Q
0–Q7
Data Inputs
Master Reset (Active LOW)
Data Outputs
© 1999 Fairchild Semiconductor Corporation DS011549 www.fairchildsemi.com
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Truth Table
74ABT273
Operating Mode Inputs Output
MR
CP D
Q
n
n
Reset (Clear) L X X L
Load “1” H
Load “0” H
H = HIGH Voltage Level stead y stat e
h = HIGH Voltage Level one setup time prior to the LOW-to-HIGH clock transition
L = LOW Voltage Level steady sta te
I = LOW Voltage Level one setup time prior to the LOW-to-HIGH clock transition
X = Immaterial
= LOW-to-HIGH clock transition
hH
lL
Logic Diagram
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
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Absolute Maximum Ratings(Note 1) Recommended Operating
Storage Temperature −65°C to +150°C
Ambient Temperature under Bias −55°C to +125°C
Junction Temperature under Bias −55°C to +150°C
V
Pin Potential to Ground Pin −0.5V to +7.0V
CC
Input Voltage (Note 2) −0.5V to +7.0V
Input Current (Note 2) −30 mA to +5.0 mA
Voltage Applied to Any Output
in the Disabled or
Power-Off State −0.5V to +4.75V
in the HIGH State −0.5V to V
Current Applied to Output
in LOW State (Max) twice the rated I
OL
DC Latchup Source Current −500 mA
(Across Comm Operating Range)
Over Voltage Latchup V
CC
Conditions
Free Air Ambient Temperature −40°C to +85°C
Supply Voltage +4.5V to +5.5V
Minimum Input Edge Rate (∆V/∆t)
Data Input 50 mV/ns
Enable Input 20 mV/ns
CC
(mA)
Note 1: Absolute maximum ratings are values beyond which the device
may be damaged or have its useful life impaired . Functional operation
under these conditions is not implied.
Note 2: Either voltage lim it or c urrent limit is sufficient to protect inputs.
+ 4.5V
DC Electrical Characteristics
74ABT273
Symbol Parameter Min Typ Max Units
V
IH
V
IL
V
CD
V
OH
V
OL
I
IH
I
BVI
I
IL
V
ID
I
OS
I
CEX
I
CCH
I
CCL
I
CCT
I
CCD
Note 3: Guaranteed but not tested.
Note 4: For 8 bits toggling, I
Input HIGH Voltage 2.0 V Recognized HIGH Signal
Input LOW Voltage 0.8 V Recognized LOW Signal
Input Clamp Diode Voltage −1.2 V Min IIN = −18 mA
Output HIGH Voltage 2.5
Output LOW Voltage 0.55 V Min IOL = 64 mA
Input HIGH Current 1
Input HIGH Current
Breakdown Test
Input LOW Current −1
Input Leakage Test 4.75 V 0.0 IID = 1.9 µA
Output Short-Circuit Current −100 −275 mA Max V
Output HIGH Leakage Current 50 µAMaxV
Power Supply Current 50 µA Max All Outputs HIGH
Power Supply Current 30 mA Max All Outputs LOW
Maximum ICC/Input Outputs Enabled 1.5 mA Max VI = VCC − 2.1V
Dynamic I
CC
No Load 0.3 mA/
< 0.5 mA/MHz.
CCD
2.0 IOH = −32 mA
1V
7 µAMaxVIN = 7.0V
−1V
V
CC
VMin
µAMax
µAMax
MHz One Bit Toggling, 50% Duty Cycle
Max
Conditions
IOH = −3 mA
VIN = 2.7V (Note 3)
= V
IN
CC
VIN = 0.5V (Note 3)
= 0.0V
IN
All Other Pins Grounded
= 0.0V
OUT
= V
OUT
CC
Data Input VI = VCC − 2.1V
All Others at VCC or GND
Outputs Open (Note 4)
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