SN74AS869 [TI]
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS; 同步8位加/减计数器型号: | SN74AS869 |
厂家: | TEXAS INSTRUMENTS |
描述: | SYNCHRONOUS 8-BIT UP/DOWN COUNTERS |
文件: | 总17页 (文件大小:288K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
SN54AS867, SN54AS869 . . . JT PACKAGE
• Fully Programmable With Synchronous
SN74ALS867A, SN74ALS869, SN74AS867,
SN74AS869 . . . DW OR NT PACKAGE
(TOP VIEW)
Counting and Loading
• SN74ALS867A and ′AS867 Have
Asynchronous Clear; SN74ALS869 and
′AS869 Have Synchronous Clear
S0
S1
A
B
C
D
E
F
G
V
CC
ENP
1
24
23
22
21
20
19
18
17
16
15
14
13
2
• Fully Independent Clock Circuit
Q
3
Simplifies Use
A
Q
B
4
• Ripple-Carry Output for n-Bit Cascading
Q
5
C
• Package Options Include Plastic
Small-Outline (DW) Packages, Ceramic
Chip Carriers (FK), and Standard Plastic
(NT) and Ceramic (JT) 300-mil DIPs
Q
D
6
Q
7
E
Q
F
8
Q
9
G
H
ENT
GND
Q
H
CLK
10
11
12
description
RCO
These synchronous, presettable, 8-bit up/down
counters feature internal-carry look-ahead
circuitry for cascading in high-speed counting
applications. Synchronous operation is provided
by having all flip-flops clocked simultaneously so
that the outputs change coincidentally with each
other when so instructed by the count-enable
(ENP, ENT) inputs and internal gating. This mode
of operation eliminates the output counting spikes
normally associated with asynchronous (ripple-
clock) counters. A buffered clock (CLK) input
triggers the eight flip-flops on the rising (positive-
going) edge of the clock waveform.
SN54AS867, SN54AS869 . . . FK PACKAGE
(TOP VIEW)
4
3
2
1 28 27 26
25
B
C
Q
Q
Q
5
B
C
D
24
23
22
21
20
19
6
D
7
NC
E
NC
8
Q
9
E
F
10
11
Q
Q
F
These counters are fully programmable; they may
be preset to any number between 0 and 255. The
load-input circuitry allows parallel loading of the
cascaded counters. Because loading is
synchronous, selecting the load mode disables
the counter and causes the outputs to agree with
the data inputs after the next clock pulse.
G
G
12 13 14 15 16 17 18
NC – No internal connection
The carry look-ahead circuitry provides for cascading counters for n-bit synchronous applications without
additional gating. Two count-enable (ENP and ENT) inputs and a ripple-carry (RCO) output are instrumental
in accomplishing this function. Both ENP and ENT must be low to count. The direction of the count is determined
by the levels of the select (S0, S1) inputs as shown in the function table. ENT is fed forward to enable RCO. RCO
thus enabled produces a low-level pulse while the count is zero (all outputs low) counting down or 255 counting
up (all outputs high). This low-level overflow-carry pulse can be used to enable successive cascaded stages.
Transitions at ENP and ENT are allowed regardless of the level of CLK. All inputs are diode clamped to minimize
transmission-line effects, thereby simplifying system design.
These counters feature a fully independent clock circuit. With the exception of the asynchronous clear on the
SN74ALS867A and ′AS867, changes at S0 and S1 that modify the operating mode have no effect on the Q
outputs until clocking occurs. For the ′AS867 and ′AS869, any time ENP and/or ENT is taken high, RCO either
goes or remains high. For the SN74ALS867A and SN74ALS869, any time ENT is taken high, RCO either goes
or remains high. The function of the counter (whether enabled, disabled, loading, or counting) is dictated solely
by the conditions meeting the stable setup and hold times.
Copyright 1995, Texas Instruments Incorporated
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.
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
description (continued)
The SN54AS867 and SN54AS869 are characterized for operation over the full military temperature range of
–55°C to 125°C. The SN74ALS867A, SN74ALS869, SN74AS867, and SN74AS869 are characterized for
operation from 0°C to 70°C.
FUNCTION TABLE
S1
L
S0
L
FUNCTION
Clear
L
H
L
Count down
Load
H
H
H
Count up
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
†
logic symbols
SN74ALS867A
CTRDIV 256
1
S0
S1
0
0
3
2
M
1
13
11
RCO
1,4CT=0
ENT
G4
23
14
3,4CT=255
ENP
CLK
G5
C6/1,4,5–/3,4,5+
0R
3
22
21
20
19
18
17
16
15
Q
A
A
B
C
D
E
F
2,6D
4
Q
B
5
Q
C
6
Q
D
7
Q
E
8
Q
F
9
Q
G
G
H
10
Q
H
SN74ALS869
CTRDIV 256
0
3
1
S0
S1
0
2
M
1
13
11
RCO
ENT
1,4CT=0
G4
23
14
3,4CT=255
ENP
CLK
G5
C6/1,4,5–/3,4,5+
0,6R
3
22
21
20
19
18
17
16
15
Q
A
A
B
C
D
E
F
2,6D
4
Q
B
5
Q
C
6
Q
D
7
Q
E
8
Q
F
9
Q
G
G
H
10
Q
H
†
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.
3
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
†
logic symbols (continued)
′AS867
CTRDIV 256
0
3
1
S0
S1
0
2
M
1
13
11
RCO
1,4,5CT=0
3,4,5CT=255
ENT
G4
23
14
ENP
CLK
G5
C6/1,4,5–/3,4,5+
0R
3
22
21
20
19
18
17
16
15
Q
A
A
B
C
D
E
F
2,6D
4
Q
B
5
Q
C
6
Q
D
7
Q
E
8
Q
F
9
Q
G
G
H
10
Q
H
′AS869
CTRDIV 256
0
3
1
S0
S1
0
2
M
1
13
11
RCO
1,4,5CT=0
3,4,5CT=255
ENT
G4
23
14
ENP
CLK
G5
C6/1,4,5–/3,4,5+
0,6R
3
22
21
20
19
18
17
16
15
Q
A
A
B
C
D
E
F
2,6D
4
Q
B
5
Q
C
6
Q
D
7
Q
E
8
Q
F
9
Q
G
G
H
10
Q
H
†
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.
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
logic diagram (positive logic)
SN74ALS867A, SN74ALS869
14
CLK
1
SN74ALS867A Only
(asynchronous clear)
S0
2
S1
23
ENP
1D
C1
22
R
3
A
Q
Q
Q
Q
A
B
C
D
1D
C1
4
21
20
19
R
B
1D
C1
R
5
C
1D
C1
R
6
D
1D
C1
7
18
17
R
E
Q
Q
E
F
1D
C1
R
8
F
1D
C1
9
16
15
R
G
Q
Q
G
H
1D
C1
10
H
R
13
RCO
11
ENT
Pin numbers shown are for the DW, JT, and NT packages.
5
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
logic diagram (positive logic)
′AS867, ′AS869
1
S0
2
′AS867 Only
(asynchronous clear)
S1
11
ENT
13
22
RCO
23
14
ENP
CLK
Q
Q
Q
Q
A
B
C
D
3
4
5
6
1D
C1
R
A
B
C
D
21
20
19
1D
C1
R
1D
C1
R
1D
C1
R
18
17
16
15
Q
Q
Q
Q
E
F
7
1D
C1
R
E
F
8
1D
C1
R
G
H
9
1D
C1
R
G
H
10
1D
C1
R
Pin numbers shown are for the DW, JT, and NT packages.
6
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
typical clear, preset, count, and inhibit sequences
The following sequence is illustrated below:
1. Clear outputs to zero (SN74ALS867A and ′AS867 are asynchronous;
SN74ALS869 and ′AS869 are synchronous.)
2. Preset to binary 252
3. Count up to 253, 254, 255, 0, 1, and 2
4. Count down to 1, 0, 255, 254, 253, and 252
5. Inhibit
S0
S1
A
B
C
D
Data
Inputs
E
F
G
H
CLK
ENP
ENT
Q
A
Q
B
Q
C
Q
D
Outputs
Q
E
Q
F
Q
G
Q
H
RCO
Sync
Clear
252 253 254 255
0
1
2
1
0
255 254 253 252
Count Down
†
Count Up
Inhibit
Async
Preset
Clear
†
ENT and ENP both must be low for counting to occur.
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
†
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
CC
Input voltage, V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I
Operating free-air temperature range, T : SN74ALS867A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
A
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.
recommended operating conditions
SN74ALS867A
MIN NOM MAX
UNIT
V
V
V
Supply voltage
4.5
2
5
5.5
V
V
CC
High-level input voltage
Low-level input voltage
IH
0.8
–0.4
8
V
IL
I
I
f
t
t
High-level output current
Low-level output current
Clock frequency
mA
mA
MHz
ns
OH
OL
0
14
10
10
15
12
12
12
3
35
clock
w(clock)
w(clear)
Pulse duration, CLK high or low
Pulse duration of clear pulse, S0 and S1 low
ns
Data inputs A–H
ENP or ENT
t
su
S0 low and S1 high (load)
S0 high and S1 low (count down)
S0 and S1 high (count up)
S0 high after S1↑ or S1 high after S0↑
Data inputs A–H
ns
Setup time before CLK↑
t
h
ns
Hold time after CLK↑
0
T
A
Operating free-air temperature
0
70
°C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
SN74ALS867A
PARAMETER
TEST CONDITIONS
UNIT
‡
MIN TYP
MAX
V
V
V
V
= 4.5 V,
I = –18 mA
–1.2
V
V
IK
CC
I
= 4.5 V to 5.5 V,
I
I
I
= –0.4 mA
= 4 mA
V
CC
–2
OH
CC
OH
OL
OL
0.25
0.35
0.4
0.5
V
OL
V
CC
= 4.5 V
V
= 8 mA
I
I
I
I
I
V
CC
V
CC
V
CC
V
CC
V
CC
= 5.5 V,
= 5.5 V,
= 5.5 V,
= 5.5 V,
= 5.5 V
V = 7 V
0.1
mA
µA
I
I
V = 2.7 V
I
20
IH
IL
V = 0.4 V
I
–0.2
–112
45
mA
mA
mA
§
V
O
= 2.25 V
–30
O
28
CC
‡
§
All typical values are at V
= 5 V, T = 25°C.
A
CC
The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, I
.
OS
8
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
switching characteristics (see Figure 1)
V
C
R
= 4.5 V to 5.5 V,
= 50 pF,
CC
L
L
= 500 Ω,
FROM
TO
(OUTPUT)
†
PARAMETER
(INPUT)
UNIT
T
A
= MIN to MAX
SN74ALS867A
MIN
35
4
MAX
f
t
t
t
t
t
t
t
t
t
t
MHz
ns
max
PLH
PHL
PLH
PHL
PLH
PHL
PHL
PLH
PHL
PLH
14
14
16
16
14
9
CLK
CLK
RCO
4
3
Any Q
ns
3
3
ns
ns
ns
ns
ENT
RCO
2
S0 or S1 (clear mode)
Any Q
8
26
16
16
16
4
S0 or S1
(count up/down)
RCO
RCO
4
S0 or S1 (clear mode)
4
†
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
9
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
†
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
CC
Input voltage, V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I
Operating free-air temperature range, T : SN74ALS869 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
A
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.
recommended operating conditions
SN74ALS869
MIN NOM MAX
UNIT
V
V
V
Supply voltage
4.5
2
5
5.5
V
V
CC
High-level input voltage
Low-level input voltage
High-level output current
Low-level output current
Clock frequency
IH
0.8
–0.4
8
V
IL
I
I
f
t
mA
mA
MHz
ns
OH
OL
0
14
10
15
13
13
13
13
3
35
clock
w(clock)
Pulse duration, CLK high or low
Data inputs A–H
ENP or ENT
S0 and S1 low (clear)
t
su
ns
Setup time before CLK↑
S0 low and S1 high (load)
S0 high and S1 low (count down)
S0 and S1 high (count up)
S0 high after S1↑ or S1 high after S0↑
Data inputs A–H
t
h
ns
Hold time after CLK↑
0
T
A
Operating free-air temperature
0
70
°C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
SN74ALS869
PARAMETER
TEST CONDITIONS
UNIT
‡
MIN TYP
MAX
V
V
V
V
= 4.5 V,
I = –18 mA
–1.2
V
V
IK
CC
I
= 4.5 V to 5.5 V,
I
I
I
= –0.4 mA
= 4 mA
V
CC
–2
OH
CC
OH
OL
OL
0.25
0.35
0.4
0.5
V
OL
V
CC
= 4.5 V
V
= 8 mA
I
I
I
I
I
V
CC
V
CC
V
CC
V
CC
V
CC
= 5.5 V,
= 5.5 V,
= 5.5 V,
= 5.5 V,
= 5.5 V
V = 7 V
0.1
mA
µA
I
I
V = 2.7 V
I
20
IH
IL
V = 0.4 V
I
–0.2
–112
45
mA
mA
mA
§
V
O
= 2.25 V
–30
O
28
CC
‡
§
All typical values are at V
= 5 V, T = 25°C.
A
CC
The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, I
.
OS
10
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
switching characteristics (see Figure 1)
V
C
R
= 4.5 V to 5.5 V,
= 50 pF,
CC
L
L
= 500 Ω,
FROM
TO
(OUTPUT)
†
PARAMETER
(INPUT)
UNIT
T
A
= MIN to MAX
SN74ALS869
MIN MAX
35
f
t
t
t
t
t
t
t
t
t
t
MHz
ns
max
PLH
PHL
PLH
PHL
PLH
PHL
PLH
PHL
PLH
PHL
4
4
3
3
3
2
4
4
4
4
14
14
16
16
14
9
CLK
CLK
ENT
RCO
Any Q
ns
ns
ns
ns
RCO
RCO
RCO
15
15
16
12
S1
(count up/down)
S0
(clear/load)
†
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
11
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
†
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
CC
Input voltage, V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I
Operating free-air temperature range, T : SN54AS867 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –55°C to 125°C
A
SN74AS867 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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.
recommended operating conditions
SN54AS867
MIN NOM
SN74AS867
MIN NOM
UNIT
MAX
MAX
V
V
V
Supply voltage
4.5
2
5
5.5
4.5
2
5
5.5
V
V
CC
High-level input voltage
Low-level input voltage
IH
0.8
–2
20
40
0.8
–2
20
50
V
IL
I
I
f
t
t
High-level output current
Low-level output current
Clock frequency
mA
mA
MHz
ns
OH
OL
clock
*
0
12.5
12.5
5
0
10
10
4
*
Pulse duration, CLK high or low
Pulse duration of clear pulse, S0 and S1 low
w(clock)
*
ns
w(clear)
Data inputs A–H
ENP or ENT
9
8
S0 low and S1 high (load)
S0 and S1 low (clear)
S0 high and S1 low (count down)
S0 and S1 high (count up)
Data inputs A–H
11
10
10
40
40
0
t
*
ns
Setup time before CLK↑
su
11
42
42
0
t *
h
Hold time after CLK↑
ns
ns
°C
Skew time between S0 and S1
t
*
8
7
skew
(maximum to avoid inadvertent clear)
T
Operating free-air temperature
–55
125
0
70
A
* On products compliant to MIL-STD-883, Class B, this parameter is based on characterization data but is not production tested.
12
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
SN54AS867
SN74AS867
PARAMETER
TEST CONDITIONS
UNIT
†
†
MIN TYP
MAX
MIN TYP
MAX
V
V
V
V
= 4.5 V,
I = –18 mA
–1.2
–1.2
V
V
IK
CC
I
= 4.5 V to 5.5 V,
I
= –2 mA
V
CC
–2
V
CC
–2
OH
CC
OH
OL
I
V
= 20 mA,
on ENT = 0.7 V
0.34
0.5
RCO
IL
V
OL
V
CC
= 4.5 V
V
Other outputs
I
= 20 mA
0.34
0.5
0.1
OL
I
I
V
V
= 5.5 V,
= 5.5 V,
V = 7 V
0.1
40
mA
I
CC
I
ENT
40
V = 2.7 V
µA
IH
IL
CC
I
Other inputs
ENT
20
20
–4
–4
I
V
CC
= 5.5 V,
V = 0.4 V
mA
I
Other inputs
–2
–2
‡
I
I
V
V
= 5.5 V,
= 5.5 V
V = 2.25 V
O
–30
–112
195
–30
–112
195
mA
mA
O
CC
134
134
CC
CC
†
‡
All typical values are at V
= 5 V, T = 25°C.
A
CC
The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, I
.
OS
switching characteristics (see Figure 1)
V
C
R
= 4.5 V to 5.5 V,
= 50 pF,
CC
L
L
= 500 Ω,
FROM
TO
(OUTPUT)
§
PARAMETER
(INPUT)
UNIT
T
A
= MIN to MAX
SN54AS867
SN74AS867
MIN
40
5
MAX
MIN
50
5
MAX
f
t
t
t
t
t
t
t
t
t
*
MHz
ns
max
31
19
12
16
19
21
16
21
23
22
16
11
15
10
17
14
17
21
PLH
PHL
PLH
PHL
PLH
PHL
PLH
PHL
PHL
CLK
CLK
RCO
6
6
3
3
Any Q
ns
ns
4
4
3
3
ENT
RCO
5
5
5
5
ns
ns
ENP
RCO
5
5
Clear (S0 or S1 low)
Any Q
7
7
* On products compliant to MIL-STD-883, Class B, this parameter is based on characterization data but is not production tested.
§
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
13
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
†
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
CC
Input voltage, V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I
Operating free-air temperature range, T : SN54AS869 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –55°C to 125°C
A
SN74AS869 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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.
recommended operating conditions
SN54AS869
MIN NOM
SN74AS869
MIN NOM
UNIT
MAX
MAX
V
V
V
Supply voltage
4.5
2
5
5.5
4.5
2
5
5.5
V
V
CC
High-level input voltage
Low-level input voltage
High-level output current
Low-level output current
Clock frequency
IH
0.7
–2
20
40
0.8
–2
20
45
V
IL
I
I
f
t
mA
mA
MHz
ns
OH
OL
clock
*
*
Pulse duration, CLK high or low
12.5
6
11
5
w(clock)
Data inputs A–H
ENP or ENT
10
13
13
52
52
0
9
S0 low and S1 high (load)
S0 and S1 low (clear)
S0 high and S1 low (count down)
S0 and S1 high (count up)
Data inputs A–H
11
11
50
50
0
t *
su
ns
Setup time before CLK↑
t *
h
Hold time after CLK↑
ns
T
A
Operating free-air temperature
–55
125
0
70
°C
* On products compliant to MIL-STD-883, Class B, this parameter is based on characterization data but is not production tested.
14
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
SN54AS869
SN74AS869
PARAMETER
TEST CONDITIONS
UNIT
V
†
†
MIN TYP
MAX
MIN TYP
MAX
V
V
V
V
V
= 4.5 V,
I = –18 mA
I
–1.2
–1.2
IK
CC
CC
CC
= 4.5 V to 5.5 V,
= 4.5 V,
I
I
I
= –2 mA
= –2 mA
V
CC
–2
OH
OH
OL
V
OH
V
CC
–2*
= 20 mA,
on ENT = 0.7 V
0.34
0.5
RCO
V
IL
V
OL
V
CC
= 4.5 V
V
Other outputs
I
= 20 mA
0.34
0.5
0.1
OL
I
I
V
V
= 5.5 V,
= 5.5 V,
V = 7 V
0.1
40
mA
I
CC
I
ENT
40
V = 2.7 V
µA
IH
IL
CC
I
Other inputs
ENT
20
20
–4
–4
I
V
CC
= 5.5 V,
V = 0.4 V
mA
I
Other inputs
–2
–2
‡
I
I
V
V
= 5.5 V,
= 5.5 V
V = 2.25 V
O
–30
–112
195
–30
–112
195
mA
mA
O
CC
134
134
CC
CC
†
‡
All typical values are at V
= 5 V, T = 25°C.
A
CC
The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, I
.
OS
switching characteristics (see Figure 1)
V
C
R
= 4.5 V to 5.5 V,
= 50 pF,
CC
L
L
= 500 Ω,
FROM
TO
(OUTPUT)
§
PARAMETER
(INPUT)
UNIT
T
A
= MIN to MAX
SN54AS869
SN74AS869
MIN
40
6
MAX
MIN
45
6
MAX
f
t
t
t
t
t
t
t
t
*
MHz
ns
max
35
20
12
16
25
21
27
21
35
18
11
15
15
17
19
18
PLH
PHL
PLH
PHL
PLH
PHL
PLH
PHL
CLK
CLK
RCO
6
6
3
3
Any Q
ns
ns
ns
4
4
3
3
ENT
ENP
RCO
RCO
6
6
5
5
6
6
* On products compliant to MIL-STD-883, Class B, this parameter is based on characterization data but is not production tested.
§
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
15
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
SN54AS867, SN54AS869
SN74ALS867A, SN74ALS869, SN74AS867, SN74AS869
SYNCHRONOUS 8-BIT UP/DOWN COUNTERS
SDAS115C – DECEMBER 1982 – REVISED JANUARY 1995
PARAMETER MEASUREMENT INFORMATION
SERIES 54ALS/74ALS AND 54AS/74AS DEVICES
7 V
R
= R1 = R2
V
CC
L
S1
R1
R
L
Test
Point
From Output
Under Test
From Output
Under Test
Test
Point
Test
Point
From Output
Under Test
C
C
L
R
L
R2
L
C
L
(see Note A)
(see Note A)
(see Note A)
LOAD CIRCUIT FOR
BI-STATE
TOTEM-POLE OUTPUTS
LOAD CIRCUIT
FOR OPEN-COLLECTOR OUTPUTS
LOAD CIRCUIT
FOR 3-STATE OUTPUTS
3.5 V
3.5 V
Timing
Input
High-Level
1.3 V
1.3 V
1.3 V
Pulse
0.3 V
0.3 V
t
h
t
w
t
su
3.5 V
3.5 V
0.3 V
Data
Input
Low-Level
1.3 V
1.3 V
1.3 V
1.3 V
Pulse
0.3 V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
VOLTAGE WAVEFORMS
PULSE DURATIONS
3.5 V
0.3 V
Output
Control
(low-level
enabling)
1.3 V
1.3 V
3.5 V
t
PZL
Input
1.3 V
1.3 V
t
PLZ
0.3 V
PHL
3.5 V
t
Waveform 1
S1 Closed
(see Note B)
t
PLH
1.3 V
V
OH
In-Phase
Output
1.3 V
1.3 V
1.3 V
V
OL
0.3 V
V
OL
t
PHZ
t
PLH
t
PZH
t
PHL
V
OH
V
Waveform 2
S1 Open
(see Note B)
OH
OL
Out-of-Phase
Output
(see Note C)
1.3 V
1.3 V
0.3 V
V
0 V
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES, 3-STATE OUTPUTS
NOTES: A.
C includes probe and jig capacitance.
L
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. When measuring propagation delay items of 3-state outputs, switch S1 is open.
D. All input pulses have the following characteristics: PRR ≤ 1 MHz, t = t = 2 ns, duty cycle = 50%.
r
f
E. The outputs are measured one at a time with one transition per measurement.
Figure 1. Load Circuits and Voltage Waveforms
16
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
IMPORTANT NOTICE
Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue
any product or service without notice, and advise customers to obtain the latest version of relevant information
to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those
pertaining to warranty, patent infringement, and limitation of liability.
TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF
DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL
APPLICATIONS”). TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, AUTHORIZED, OR
WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT DEVICES OR SYSTEMS OR OTHER
CRITICAL APPLICATIONS. INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO
BE FULLY AT THE CUSTOMER’S RISK.
In order to minimize risks associated with the customer’s applications, adequate design and operating
safeguards must be provided by the customer to minimize inherent or procedural hazards.
TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent
that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other
intellectual property right of TI covering or relating to any combination, machine, or process in which such
semiconductor products or services might be or are used. TI’s publication of information regarding any third
party’s products or services does not constitute TI’s approval, warranty or endorsement thereof.
Copyright 1998, Texas Instruments Incorporated
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SN74AS869DW
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