SN54ALS874B, SN74ALS874B, SN74ALS876A
SN74AS874, SN74AS876
DUAL 4-BIT D-TYPE EDGE-TRIGGERED FLIP-FLOPS
SDAS061C APRIL 1982 REVISED JANUARY 1995
Copyright
1995, Texas Instruments Incorporated
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
3-State Buffer-Type Outputs Drive Bus
Lines Directly
Bus-Structured Pinout
Choice of True or Inverting Logic
SN54ALS874B, SN74ALS874B,
SN74AS874 Have True Outputs
SN74ALS876A, SN74AS876 Have
Inverting Outputs
Asynchronous Clear
Package Options Include Plastic
Small-Outline (DW) Packages, Plastic (FN)
and Ceramic (FK) Chip Carriers, and
Standard Plastic (NT) and Ceramic (JT)
300-mil DIPs
description
These dual 4-bit D-type edge-triggered flip-flops
feature 3-state outputs designed specifically as
bus drivers. They are particularly suitable for
implementing buffer registers, I/O ports,
bidirectional bus drivers, and working registers.
The edge-triggered flip-flops enter data on the
low-to-high transition of the clock (CLK) input.
The SN54ALS874B, SN74ALS874B, and
SN74AS874 have clear (CLR) inputs and
noninverting Q outputs. The SN74ALS876A and
SN74AS876 have preset (PRE) inputs and
inverting Q outputs; taking PRE low causes the
four Q or Q outputs to go low independently of the
clock.
The SN54ALS874B is characterized for operation
over the full military temperature range of 55
C
to 125
C. The SN74ALS874B, SN74ALS876A,
SN74AS874, and SN74AS876 devices are
characterized for operation from 0
C to 70
C.
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
1CLR
1OE
1D1
1D2
1D3
1D4
2D1
2D2
2D3
2D4
2OE
GND
V
CC
1CLK
1Q1
1Q2
1Q3
1Q4
2Q1
2Q2
2Q3
2Q4
2CLK
2CLR
SN54ALS874B . . . JT PACKAGE
SN74ALS874B, SN74AS874 . . . DW OR NT PACKAGE
(TOP VIEW)
3 2
1
13 14
5
6
7
8
9
10
11
1Q2
1Q3
1Q4
NC
2Q1
2Q2
2Q3
1D2
1D3
1D4
NC
2D1
2D2
2D3
4
15 16 17 18
2OE
GND
NC
2CLR
2CLK
2Q4
1D1
1OE
1CLR
NC
SN54ALS874B . . . FK PACKAGE
(TOP VIEW)
28 27 26
25
24
23
22
21
20
19
12
2D4
1CLK
1Q1
CC
V
NC No internal connection
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
1PRE
1OE
1D1
1D2
1D3
1D4
2D1
2D2
2D3
2D4
2OE
GND
V
CC
1CLK
1Q1
1Q2
1Q3
1Q4
2Q1
2Q2
2Q3
2Q4
2CLK
2PRE
SN74ALS876A, SN74AS876 . . . DW OR NT PACKAGE
(TOP VIEW)
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
SN54ALS874B, SN74ALS874B, SN74ALS876A
SN74AS874, SN74AS876
DUAL 4-BIT D-TYPE EDGE-TRIGGERED FLIP-FLOPS
SDAS061C APRIL 1982 REVISED JANUARY 1995
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
Function Tables
SN54ALS874B, SN74ALS874B, SN74AS874
(each flip-flop)
INPUTS
OUTPUT
OE
CLR
CLK
D
Q
L
L
X
X
L
L
H
H
H
L
H
L
L
L
H
L
X
Q0
H
X
X
X
Z
SN74ALS876A, SN74AS876
(each flip-flop)
INPUTS
OUTPUT
OE
PRE
CLK
D
Q
L
L
X
X
L
L
H
H
L
L
H
L
H
L
H
L
X
Q0
H
X
X
X
Z
logic symbols
1OE
23
1CLK
EN
2
C1
SN54ALS874B, SN74ALS874B, SN74AS874
1CLR
R
1
1D
3
1D1
4
1D2
5
1D3
6
1D4
1Q1
22
1Q2
21
1Q3
20
1Q4
19
2OE
14
2CLK
EN
11
C1
2CLR
R
13
1D
7
2D1
8
2D2
9
2D3
10
2D4
2Q1
18
2Q2
17
2Q3
16
2Q4
15
1OE
23
1CLK
EN
2
C1
SN74ALS876A, SN74AS876
1PRE
S
1
1D
3
1D1
4
1D2
5
1D3
6
1D4
22
21
20
19
2OE
14
2CLK
EN
11
C1
2PRE
S
13
1D
7
2D1
8
2D2
9
2D3
10
2D4
18
17
16
15
1Q1
1Q2
1Q3
1Q4
2Q1
2Q2
2Q3
2Q4
These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
Pin numbers shown are for the DW, JT, and NT packages.
SN54ALS874B, SN74ALS874B, SN74ALS876A
SN74AS874, SN74AS876
DUAL 4-BIT D-TYPE EDGE-TRIGGERED FLIP-FLOPS
SDAS061C APRIL 1982 REVISED JANUARY 1995
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic diagrams (positive logic)
R
C1
1D
D1
Q1
R
C1
1D
D2
Q2
R
C1
1D
D3
Q3
R
C1
1D
D4
Q4
OE
CLK
CLR
SN54ALS874B, SN74ALS874B, SN74AS874
(each quad flip-flop)
S
C1
1D
D1
Q1
S
C1
1D
D2
Q2
S
C1
1D
D3
Q3
S
C1
1D
D4
Q4
OE
CLK
PRE
SN74ALS876A, SN74AS876
(each quad flip-flop)
Pin numbers shown are for the DW, JT, and NT packages.
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
CC
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage, V
I
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage applied to a disabled 3-state output
5.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, T
A
: SN54ALS874B
55
C to 125
C
. . . . . . . . . . . . . . . . . . . . . . . . . . .
SN74ALS874B, SN74ALS876A
0
C to 70
C
. . . . . . . . . . . . . . . . .
Storage temperature range
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
SN54ALS874B, SN74ALS874B, SN74ALS876A
SN74AS874, SN74AS876
DUAL 4-BIT D-TYPE EDGE-TRIGGERED FLIP-FLOPS
SDAS061C APRIL 1982 REVISED JANUARY 1995
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
recommended operating conditions
SN54ALS874B
SN74ALS874B
SN74ALS876A
UNIT
MIN
NOM
MAX
MIN
NOM
MAX
VCC
Supply voltage
4.5
5
5.5
4.5
5
5.5
V
VIH
High-level input voltage
2
2
V
VIL
Low-level input voltage
0.7
0.8
V
IOH
High-level output current
1
2.6
mA
IOL
Low-level output current
12
24
mA
fclock
Clock frequency
0
25
0
30
MHz
PRE or CLR low
15
10
tw
Pulse duration
CLK high
20
16.5
ns
CLK low
20
16.5
t
Set p time before CLK
Data
15
15
ns
tsu
Setup time before CLK
PRE or CLR inactive
15
10
ns
th
Hold time, data after CLK
4
0
ns
TA
Operating free-air temperature
55
125
0
70
C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
SN54ALS874B
SN74ALS874B
SN74ALS876A
UNIT
MIN
TYP
MAX
MIN
TYP
MAX
VIK
VCC = 4.5 V,
II = 18 mA
1.2
1.2
V
VCC = 4.5 V to 5.5 V,
IOH = 0.4 mA
VCC 2
VCC 2
VOH
VCC = 4 5 V
IOH = 1 mA
2.4
3.3
V
VCC = 4.5 V
IOH = 2.6 mA
2.4
3.2
VOL
VCC = 4 5 V
IOL = 12 mA
0.25
0.4
0.25
0.4
V
VOL
VCC = 4.5 V
IOL = 24 mA
0.35
0.5
V
IOZH
VCC = 5.5 V,
VO = 2.7 V
20
20
A
IOZL
VCC = 5.5 V,
VO = 0.4 V
20
20
A
II
VCC = 5.5 V,
VI = 7 V
0.1
0.1
mA
IIH
VCC = 5.5 V,
VI = 2.7 V
20
20
A
IIL
VCC = 5.5 V,
VI = 0.4 V
0.2
0.2
mA
IO
VCC = 5.5 V,
VO = 2.25 V
20
112
30
112
mA
Outputs high
14
21
14
21
ALS874B
VCC = 5.5 V
Outputs low
19
30
19
30
ICC
Outputs disabled
20
32
20
32
mA
ICC
Outputs high
14
21
mA
SN74ALS876A
VCC = 5.5 V
Outputs low
18
29
Outputs disabled
20
31
All typical values are at VCC = 5 V, TA = 25
C.
The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
SN54ALS874B, SN74ALS874B, SN74ALS876A
SN74AS874, SN74AS876
DUAL 4-BIT D-TYPE EDGE-TRIGGERED FLIP-FLOPS
SDAS061C APRIL 1982 REVISED JANUARY 1995
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500
,
R2 = 500
,
TA = MIN to MAX
UNIT
SN54ALS874B
SN74ALS874B
MIN
MAX
MIN
MAX
fmax
25
30
MHz
tPLH
CLK
An Q
4
18
4
14
ns
tPHL
CLK
Any Q
4
16
4
14
ns
tPHL
CLR
Any Q
5
23
5
17
ns
tPZH
OE
An Q
4
24
4
18
ns
tPZL
OE
Any Q
4
21
4
18
ns
tPHZ
OE
Any Q
2
15
2
10
ns
tPLZ
OE
Any Q
3
22
3
12
ns
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500
,
R2 = 500
,
TA = MIN to MAX
UNIT
SN74ALS876A
MIN
MAX
fmax
30
MHz
tPLH
CLK
An Q
4
14
ns
tPHL
CLK
Any Q
4
14
ns
tPHL
PRE
Any Q
6
19
ns
tPZH
OE
An Q
4
18
ns
tPZL
OE
Any Q
4
18
ns
tPHZ
OE
Any Q
2
10
ns
tPLZ
OE
Any Q
3
13
ns
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
CC
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage, V
I
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, T
A
: SN74AS874, SN74AS876
0
C to 70
C
. . . . . . . . . . . . . . . . . . . . . .
Storage temperature range
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
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