Fairchild DM74LS169AM Synchronous 4-bit up/down binary counter Datasheet

DM74LS169A
Synchronous 4-Bit Up/Down Binary Counter
General Description
This synchronous presettable counter features an internal
carry look-ahead for cascading in high-speed counting applications. Synchronous operation is provided by having all
flip-flops clocked simultaneously, so that the outputs all
change at the same time when so instructed by the
count-enable inputs and internal gating. This mode of operation helps eliminate the output counting spikes that are normally associated with asynchronous (ripple clock) counters.
A buffered clock input triggers the four master-slave flip-flops
on the rising edge of the clock waveform.
This counter is fully programmable; that is, the outputs may
each be preset either high or low. The load input circuitry allows loading with the carry-enable output of cascaded
counters. As loading is synchronous, setting up a low level at
the load input disables the counter and causes the outputs to
agree with the data inputs after the next clock pulse.
The carry look-ahead circuitry permits cascading counters
for n-bit synchronous applications without additional gating.
Both count-enable inputs (P and T) must be low to count.
The direction of the count is determined by the level of the
up/down input. When the input is high, the counter counts
up; when low, it counts down. Input T is fed forward to enable
the carry outputs. The carry output thus enabled will produce
a low-level output pulse with a duration approximately equal
to the high portion of the QA output when counting up, and
approximately equal to the low portion of the QA output when
counting down. This low-level overflow carry pulse can be
used to enable successively cascaded stages. Transitions at
the enable P or T inputs are allowed regardless of the level
of the clock input. All inputs are diode clamped to minimize
transmission-line effects, thereby simplifying system design.
This counter features a fully independent clock circuit.
Changes at control inputs (enable P, enable T, load, up/
down), which modify the operating mode, have no effect until
clocking occurs. The function of the counter (whether enabled, disabled, loading, or counting) will be dictated solely
by the conditions meeting the stable setup and hold times.
Features
n Fully synchronous operation for counting and
programming.
n Internal look-ahead for fast counting.
n Carry output for n-bit cascading.
n Fully independent clock circuit
Connection Diagram
Dual-In-Line Package
DS006401-1
Order Number 54LS169DMQB, 54LS169FMQB, 54LS169LMQB,
DM54LS169AJ, DM54LS169AW, DM74LS169AM or DM74LS169AN
See Package Number E20A, J16A, M16A, N16E or W16A
© 1998 Fairchild Semiconductor Corporation
DS006401
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DM74LS169A Synchronous 4-Bit Up/Down Binary Counter
April 1998
Absolute Maximum Ratings (Note 1)
Supply Voltage
Input Voltage
Operating Free Air Temperature Range
DM54LS and 54LS
DM74LS
Storage Temperature Range
7V
7V
−55˚C to +125˚C
0˚C to +70˚C
−65˚C to +150˚C
Recommended Operating Conditions
Symbol
Parameter
DM54LS169A
DM74LS169A
Units
Min
Nom
Max
Min
Nom
Max
4.5
5
5.5
4.75
5
5.25
VCC
Supply Voltage
VIH
High Level Input Voltage
VIL
Low Level Input Voltage
0.7
0.8
V
IOH
High Level Output Current
−0.4
−0.4
mA
IOL
Low Level Output Current
fCLK
Clock Frequency (Note 2)
2
2
4
0
25
20
8
mA
0
25
MHz
0
20
MHz
Clock Frequency (Note 3)
0
tW
Clock Pulse Width (Note 4)
25
25
tSU
Setup Time
Data
20
20
Enable
20
20
Load
25
25
U/D
30
30
(Note 4)
ns
T or P
tH
Hold Time (Note 4)
TA
Free Air Operating Temperature
V
V
ns
0
0
−55
125
ns
0
70
˚C
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” table are not guaranteed at the absolute maximum ratings. The “Recommended Operating
Conditions” table will define the conditions for actual device operation.
Note 2: CL = 15 pF, RL = 2 kΩ, TA = 25˚C and VCC = 5V.
Note 3: CL = 50 pF, RL = 2 kΩ, TA = 25˚C and VCC = 5V.
Note 4: TA = 25˚C and VCC = 5V.
Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
(Note 5)
VI
Input Clamp Voltage
VOH
High Level Output
Voltage
VOL
Low Level Output
Voltage
Input Current @ Max
II
Input Voltage
IIH
High Level Input
Current
IIL
Low Level Input
Current
IOS
Short Circuit
Output Current
ICC
Supply Current
VCC = Min, II = −18 mA
VCC = Min, IOH = Max
VIL = Max, VIH = Min
VCC = Min, IOL = Max
VIL = Max, VIH = Min
IOL = 4 mA, VCC = Min
VCC = Max
VI = 7V
VCC = Max
−1.5
DM54
2.5
DM74
2.7
3.4
3.4
DM54
0.25
DM74
0.35
0.4
0.5
DM74
0.25
0.4
Enable T
0.2
Others
0.1
Enable T
40
VI = 2.7V
VCC = Max
Others
20
Enable T
−0.8
VI = 0.4V
VCC = Max
Others
−0.4
DM54
−20
−100
(Note 6)
VCC = Max(Note 7)
DM74
−20
−100
20
34
Note 5: All typicals are at VCC = 5V and TA = 25˚C.
Note 6: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 7: ICC is measured after a momentary 4.5V, then ground, is applied to the CLOCK with all other inputs grounded and all the outputs open.
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2
V
V
V
mA
µA
mA
mA
mA
Switching Characteristic
at VCC = 5V and TA = 25˚C (for Test Waveforms and Output Load)
RL = 2 kΩ
From (Input)
Symbol
Parameter
To (Output)
CL = 15 pF
Min
fMAX
Maximum Clock
Max
25
CL = 50 pF
Min
Units
Max
20
MHz
Frequency
tPLH
Propagation Delay Time
Low to High Level Output
tPHL
Propagation Delay Time
High to Low Level Output
tPLH
Propagation Delay Time
Low to High Level Output
tPHL
Propagation Delay Time
High to Low Level Output
tPLH
tPHL
tPLH
Clock to
Clock to
Clock to
Enable T to
Propagation Delay Time
Enable T to
High to Low Level Output
Ripple Carry
High to Low Level Output
ns
35
44
ns
20
24
ns
23
32
ns
18
24
ns
18
28
ns
25
30
ns
29
38
ns
Any Q
Ripple Carry
Propagation Delay Time
39
Any Q
Propagation Delay Time
Propagation Delay Time
35
Ripple Carry
Low to High Level Output
Low to High Level Output
tPHL
Clock to
Ripple Carry
Up/Down to
Ripple Carry (Note 8)
Up/Down to
Ripple Carry (Note 8)
Note 8: The propagation delay from UP/DOWN to RIPPLE CARRY must be measured with the counter at either a minimum or a maximum count. As the logic level
of the up/down input is changed, the ripple carry output will follow. If the count is minimum, the ripple carry output transition will be in phase. If the count is maximum,
the ripple carry output will be out of phase.
3
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Logic Diagram
LS169A Binary Counter
DS006401-2
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4
Timing Diagram
LS169A Binary Counters
Typical Load, Count, and Inhibit Sequences
DS006401-3
5
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Physical Dimensions
inches (millimeters) unless otherwise noted
Ceramic Leadless Chip Carrier Package (E)
Order Number 54LS169LMQB
Package Number E20A
16-Lead Ceramic Dual-In-Line Package (J)
Order Number 54LS169DMQB or DM54LS169AJ
Package Number J16A
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6
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
16-Lead Small Outline Molded Package (M)
Order Number DM74LS169AM
Package Number M16A
16-Lead Molded Dual-In-Line Package (N)
Order Number DM74LS169AN
Package Number N16E
7
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DM74LS169A Synchronous 4-Bit Up/Down Binary Counter
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
16-Lead Ceramic Flat Package (W)
Order Number 54LS169FMQB or DM54LS169AW
Package Number W16A
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2. A critical component in any component of a life support
1. Life support devices or systems are devices or sysdevice or system whose failure to perform can be reatems which, (a) are intended for surgical implant into
sonably expected to cause the failure of the life support
the body, or (b) support or sustain life, and (c) whose
device or system, or to affect its safety or effectiveness.
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.
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