2000 Fairchild Semiconductor Corporation
DS009827
www.fairchildsemi.com
October 1988
Revised March 2000
DM74LS299
8-
Input
Uni
ver
sal
Shif
t/
Stor
age
Regist
er
wit
h
Comm
o
n
Par
a
ll
el
I/
O Pi
ns
DM74LS299
8-Input Universal Shift/Storage Register with
Common Parallel I/O Pins
General Description
The DM74LS299 is an 8-bit universal shift/storage register
with 3-STATE outputs. Four modes of operation are possi-
ble: hold (store), shift left, shift right and load data. The par-
allel load inputs and flip-flop outputs are multiplexed to
reduce the total number of package pins. Separate outputs
are provided for flip-flops Q0 and Q7 to allow easy cascad-
ing. A separate active LOW Master Reset is used to reset
the register.
Features
s
Common I/O for reduced pin count
s
Four operation modes: shift left, shift right, load and
store
s
Separate shift right serial input and shift left serial input
for easy cascading
s
3-STATE outputs for bus oriented applications
Ordering Code:
Devices also available in Tape and Reel. Specify by appending the suffix letter "X" to the ordering code.
Logic Symbol
V
CC
=
Pin 20
GND
=
Pin 10
Pin Descriptions
Connection Diagram
Order Number
Package Number
Package Description
DM74LS299WM
M20B
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74LS299N
N20A
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Pin
Names
Description
CP
Clock Pulse Input (Active Rising Edge)
D
S0
Serial Data Input for Right Shift
D
S7
Serial Data Input for Left Shift
S0, S1
Mode Select Inputs
MR
Asynchronous Master Reset Input (Active LOW)
OE1, OE2 3-STATE Output Enable Inputs (Active LOW)
I/O0I/O7 Parallel Data Inputs or 3-STATE Parallel Outputs
Q0Q7
Serial Outputs
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2
DM74LS299
Functional Description
The DM74LS299 contains eight edge-triggered D-type flip-
flops and the interstage logic necessary to perform syn-
chronous shift left, shift right, parallel load and hold opera-
tions. The type of operation is determined by the S0 and
S1, as shown in the Mode Select Table. All flip-flop outputs
are brought out through 3-STATE buffers to separate I/O
pins that also serve as data inputs in the parallel load
mode. Q0 and Q7 are also brought out on other pins for
expansion in serial shifting of longer words.
A LOW signal on MR overrides the Select and CP inputs
and resets the flip-flops. All other state changes are initi-
ated by the rising edge of the clock. Inputs can change
when the clock is in either state provided only that the rec-
ommended setup and hold times, relative to the rising edge
of CP, are observed.
A HIGH signal on either OE1 or OE2 disables the 3-STATE
buffers and puts the I/O pins in the high impedance state.
In this condition the shift, hold, load and reset operations
can still occur. The 3-STATE buffers are also disabled by
HIGH signals on both S0 and S1 in preparation for a paral-
lel load operation.
Mode Select Table
H
=
HIGH Voltage Level
L
=
LOW Voltage Level
X
=
Immaterial
=
LOW-to-HIGH Clock (CP) Transition
Logic Diagram
Inputs
Response
MR
S1 S0 CP
L
X
X
X
Asynchronous Reset; Q0Q7
=
LOW
H
H
H
Parallel Load; I/O
n
Q
n
H
L
H
Shift Right; D
S0
Q0, Q0
Q1, etc.
H
H
L
Shift Left; D
S7
Q7, Q7
Q6, etc.
H
L
L
X
Hold
3
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DM74LS299
Absolute Maximum Ratings
(Note 1)
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.
Recommended Operating Conditions
Supply Voltage
7V
Input Voltage
7V
Operating Free Air Temperature Range
0
C to
+
70
C
Storage Temperature Range
-
65
C to
+
150
C
Symbol
Parameter
Min
Nom
Max
Units
V
CC
Supply Voltage
4.75
5
5.25
V
V
IH
HIGH Level Input Voltage
2
V
V
IL
LOW Level Input Voltage
0.8
V
I
OH
HIGH Level Output Current
Q0, Q7
-
0.4
mA
I/O0I/O7
-
2.6
mA
I
OL
LOW Level Output Current
Q0, Q7
8
mA
I/O0I/O7
24
mA
T
A
Free Air Operating Temperature
0
70
C
t
S
(H)
Setup Time HIGH or LOW
24
ns
t
S
(L)
S0 or S1 to CP
24
t
H
(H)
Hold Time HIGH or LOW
0
ns
t
H
(L)
S0 or S1 to CP
0
t
S
(H)
Setup Time HIGH or LOW
10
ns
t
S
(L)
I/O
n
, D
S0
, D
S7
to CP
10
t
H
(H)
Hold Time HIGH or LOW
0
ns
t
H
(L)
I/O
n
, D
S0
, D
S7
to CP
0
t
W
(H)
CP Pulse Width HIGH or LOW
15
ns
t
W
(L)
15
t
W
(L)
MR Pulse Width LOW
15
ns
t
REC
Recovery Time
10
ns
MR to CP
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4
DM74LS299
Electrical Characteristics
Over recommended operating free air temperature range (unless otherwise noted)
Note 2: All typicals are at V
CC
=
5V, T
A
=
25
C.
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Switching Characteristics
V
CC
=
+
5.0V, T
A
=
+
25
C
Symbol
Parameter
Conditions
Min
Typ
Max
Units
(Note 2)
V
I
Input Clamp Voltage
V
CC
=
Min, I
I
=
-
18 mA
-
1.5
V
V
OH
HIGH Level
V
CC
=
Min, I
OH
=
Max
Q0, Q7
2.7
3.4
V
Output Voltage
V
IL
=
Max
I/O0I/O7
2.4
V
OL
LOW
Level V
CC
=
Min, I
OL
=
Max
0.35
0.5
Output Voltage
V
IH
=
Min
V
I
OL
=
4 mA, V
CC
=
Min
0.25
0.4
I
I
Input Current @ Max
V
CC
=
Max
Inputs
0.1
mA
Input Voltage
V
I
=
7V
Sn
0.2
mA
I
IH
HIGH Level
V
CC
=
Max, V
I
=
2.7V
Sn
40
A
Input Current
Inputs
20
A
I
IL
LOW
Level V
CC
=
Max, V
I
=
0.4V
Sn
-
0.8
mA
Input Current
Inputs
-
0.4
mA
I
OS
Short Circuit
V
CC
=
Max
Q
0
, Q
7
-
20
-
100
mA
Output Current
(Note 3)
I/O
0
I/O
7
-
30
-
130
I
CC
Supply Current
V
CC
=
Max, OE
=
4.5V
60
mA
I
OZH
3-STATE Output Off
V
CC
=
Max
40
A
Current HIGH
V
O
=
2.7V
I
OZL
3-STATE Output Off
V
CC
=
Max
-
400
A
Current Low
V
O
=
0.4V
Symbol
Parameter
R
L
=
2 k
Units
C
L
=
15 pF
Min
Max
f
MAX
Maximum Input Frequency
35
MHz
t
PLH
Propagation Delay
26
ns
t
PHL
CP to Q0 or Q7
28
t
PLH
Propagation Delay
25
ns
t
PHL
CP to I/O
n
35
t
PHL
Propagation Delay
28
ns
MR to Q0 or Q7
t
PHL
Propagation Delay
35
ns
MR to I/O
n
t
PZH
Output Enable Time
18
ns
t
PZL
25
t
PHZ
Output Disable Time
15
ns
t
PLZ
20
5
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DM74LS299
Physical Dimensions
inches (millimeters) unless otherwise noted
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Package Number M20B
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