SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
•
•
•
DW OR N PACKAGE
(TOP VIEW)
Local Bus-Latch Capability
Choice of True or Inverting Logic
Package Options Include Plastic
Small-Outline (DW) Packages and Standard
Plastic (N) 300-mil DIPs
DEVICE
OUTPUT
LOGIC
SN74ALS620A
3 state
Inverting
SN74ALS621A
Open collector
True
SN74ALS623A, SN74AS623
3 state
OEAB
A1
A2
A3
A4
A5
A6
A7
A8
GND
True
description
1
20
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
VCC
OEBA
B1
B2
B3
B4
B5
B6
B7
B8
These octal bus transceivers are designed for asynchronous two-way communication between data buses. The
control-function implementation allows for maximum flexibility in timing.
These devices allow data transmission from the A bus to the B bus or from the B bus to the A bus, depending
upon the logic levels at the output-enable (OEAB and OEBA) inputs.
The output-enable inputs disable the device so that the buses are effectively isolated. The dual-enable
configuration gives the transceivers the capability to store data by simultaneously enabling OEAB and OEBA.
Each output reinforces its input in this transceiver configuration. When both OEAB and OEBA are enabled and
all other data sources to the two sets of bus lines are in the high-impedance state, both sets of bus lines (16 total)
remain at their last states. The 8-bit codes appearing on the two sets of buses are identical for the
SN74ALS621A, SN74ALS623A, and SN74AS623 or complementary for the SN74ALS620A.
The -1 versions of the SN74ALS620A and SN74ALS621A are identical to the standard versions, except that
the recommended maximum IOL is increased to 48 mA in the -1 versions.
The SN74ALS620A, SN74ALS621A, SN74ALS623A, and SN74AS623 are characterized for operation from
0°C to 70°C.
FUNCTION TABLE
INPUTS
OPERATION
OEBA
OEAB
SN74ALS620A
SN74ALS621A
SN74ALS623A
SN74AS623
L
L
B data to A bus
B data to A bus
H
H
A data to B bus
A data to B bus
H
L
Isolation
Isolation
H
B data to A bus,
A data to B bus
B data to A bus,
A data to B bus
L
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.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
logic symbols†
SN74ALS620A
19
OEBA
EN1
1
OEAB
EN2
2
A1
2
3
A2
A3
A4
A5
A6
A7
A8
18
1
17
4
16
5
15
6
14
7
13
8
12
9
11
19
OEAB
A1
A2
A3
A4
A5
A6
A7
A8
1
2
3
19
EN1
OEBA
EN2
OEAB
18
1
2
17
4
16
5
15
6
14
7
13
8
12
9
11
B1
B2
A1
A2
B3
A3
B4
A4
B5
B6
B7
B8
A5
A6
A7
A8
1
2
3
B3
B4
B5
B6
B7
B8
POST OFFICE BOX 655303
EN1
EN2
18
1
2
17
4
16
5
15
6
14
7
13
8
12
9
11
† These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
2
B2
SN74ALS623A, SN74AS623
SN74ALS621A
OEBA
B1
• DALLAS, TEXAS 75265
B1
B2
B3
B4
B5
B6
B7
B8
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
logic diagrams (positive logic)
SN74ALS620A
OEBA
OEAB
SN74ALS621A
19
OEBA
1
OEAB
19
1
18
A1
18
2
B1
A1
2
To Seven Other Transceivers
B1
To Seven Other Transceivers
SN74ALS623A, SN74AS623
OEBA
OEAB
A1
19
1
2
18
B1
To Seven Other Transceivers
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, VI: All inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V
Operating free-air temperature range, TA: SN74ALS620A, SN74ALS623A . . . . . . . . . . . . . . . . . 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.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
recommended operating conditions
SN74ALS620A
SN74ALS623A
VCC
VIH
Supply voltage
VIL
IOH
Low-level input voltage
IOL
TA
High-level input voltage
UNIT
MIN
NOM
MAX
4.5
5
5.5
2
V
V
0.8
V
High-level output current
– 15
mA
Low-level output current
24
mA
70
°C
Operating free-air temperature
0
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
SN74ALS620A
SN74ALS623A
MIN
VIK
VOH
VOL
II
Control inputs
A or B ports
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
II = – 18 mA
IOH = – 0.4 mA
VCC = 4
4.5
5V
IOH = – 3 mA
IOH = – 15 mA
VCC = 4
4.5
5V
IOL = 12 mA
IOL = 24 mA‡
VCC = 5
5.5
5V
VI = 7 V
VI = 5.5 V
IIH
Control inputs
A or B ports§
VCC = 5
5.5
5V
V,
VI = 2
2.7
7V
IIL
Control inputs
A or B ports§
5V
VCC = 5
5.5
V,
4V
VI = 0
0.4
VCC = 5.5 V,
VO = 2.25 V
Outputs high
IO¶
SN74ALS620A
VCC = 5.5 V
ICC
SN74ALS623A
VCC = 5.5 V
TYP†
UNIT
MAX
– 1.2
VCC – 2
2.4
V
V
3.2
2
0.25
0.4
0.35
0.5
0.1
0.1
20
20
– 0.1
– 0.1
– 30
– 112
24
34
Outputs low
31
44
Outputs disabled
33
47
Outputs high
32
43
Outputs low
39
50
Outputs disabled
42
V
mA
µA
mA
mA
mA
55
† All typical values are at VCC = 5 V, TA = 25°C.
‡ Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V
§ For I/O ports, the parameters IIH and IIL include the off-state output current.
¶ The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500 Ω,
R2 = 500 Ω,
TA = MIN to MAX†
SN74ALS620A
tPLH
tPHL
A
B
tPLH
tPHL
B
A
tPZH
tPZL
OEBA
A
tPHZ
tPLZ
OEBA
A
tPZH
tPZL
OEAB
B
tPHZ
tPLZ
OEAB
B
UNIT
SN74ALS623A
MIN
MAX
MIN
MAX
2
10
2
13
2
10
3
11
2
10
2
13
2
10
3
11
3
17
5
22
5
25
5
22
2
12
2
16
3
18
2
19
3
18
5
22
5
25
5
22
2
12
2
16
3
18
2
19
ns
ns
ns
ns
ns
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, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, VI: All inputs and I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Operating free-air temperature range, TA: SN74ALS621A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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
SN74ALS621A
MIN
NOM
MAX
4.5
5
5.5
UNIT
VCC
VIH
Supply voltage
VIL
VOH
Low-level input voltage
0.8
High-level output voltage
5.5
V
Low level output current
Low-level
24
48§
mA
70
°C
IOL
High-level input voltage
2
TA
Operating free-air temperature
§ Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
0
V
V
V
mA
5
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
SN74ALS621A
TYP†
MAX
TEST CONDITIONS
MIN
VIK
IOH
VCC = 4.5 V,
VCC = 4.5 V,
II = – 18 mA
VOH = 5.5 V
VOL
5V
VCC = 4
4.5
IOL = 24 mA
IOL = 48 mA‡
VCC = 5
5.5
5V
VI = 7 V
VI = 5.5 V
II
Control inputs
A or B ports
IIH
Control inputs
A or B ports§
VCC = 5
5.5
5V
V,
VI = 2
2.7
7V
IIL
Control inputs
A or B ports§
VCC = 5
5.5
5V
V,
VI = 0
0.4
4V
VCC = 5
5.5
5V
ICC
– 1.5
0.1
0.35
0.5
0.35
0.5
0.1
0.1
20
20
– 0.1
– 0.1
Outputs high
29
40
Outputs low
35
48
UNIT
V
mA
V
mA
µA
mA
mA
† All typical values are at VCC = 5 V, TA = 25°C.
‡ Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V
§ For I/O ports, the parameters IIH and IIL include the off-state output current.
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 680 Ω,
TA = MIN to MAX¶
UNIT
SN74ALS621A
tPLH
tPHL
A
B
tPLH
tPHL
B
A
tPLH
tPHL
OEBA
A
tPLH
tPHL
OEAB
B
MIN
MAX
10
33
5
20
10
33
5
20
10
39
12
35
10
39
12
35
¶ For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
6
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
ns
ns
ns
ns
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, VI: All inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V
Operating free-air temperature range, TA: SN74AS623 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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
SN74AS623
MIN
NOM
MAX
4.5
5
5.5
UNIT
VCC
VIH
Supply voltage
VIL
IOH
Low-level input voltage
0.8
V
High-level output current
– 15
mA
IOL
TA
Low-level output current
64
mA
70
°C
High-level input voltage
2
Operating free-air temperature
V
V
0
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
VOH
VOL
II
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
II = – 18 mA
IOH = – 2 mA
VCC = 4
4.5
5V
IOH = – 3 mA
IOH = – 15 mA
VCC = 4.5 V,
Control inputs
A or B ports
VCC = 5
5.5
5V
VCC = 5
5.5
5V
V,
VI = 2
2.7
7V
IIL
Control inputs
A or B ports§
5V
VCC = 5
5.5
V,
4V
VI = 0
0.4
VCC = 5.5 V,
VO = 2.25 V
Outputs high
VCC = 5.5 V
VCC – 2
2.4
Outputs low
UNIT
V
V
3.2
2
0.35
0.55
0.1
VI = 5.5 V
Control inputs
A or B ports§
ICC
– 1.2
IOL = 64 mA
VI = 7 V
IIH
IO¶
SN74AS623
TYP‡
MAX
MIN
0.1
20
70
– 0.5
– 0.75
– 30
– 150
57
93
16
189
V
mA
µA
mA
mA
mA
Outputs disabled
71
116
‡ All typical values are at VCC = 5 V, TA = 25°C.
§ For I/O ports, the parameters IIH and IIL include the off-state output current.
¶ The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
7
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500 Ω,
R2 = 500 Ω,
TA = MIN to MAX†
UNIT
SN74AS623
tPLH
tPHL
A
B
tPLH
tPHL
B
A
tPZH
tPZL
OEBA
A
tPHZ
tPLZ
OEBA
A
tPZH
tPZL
OEAB
B
tPHZ
tPLZ
OEAB
B
MIN
MAX
1
9
1
8
1
9
1
8.5
2
11
2
10
1
7.5
1
11.5
2
11.5
2
11
1
7
1
9
† For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
8
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
ns
ns
ns
ns
ns
ns
SN74ALS620A, SN74ALS621A, SN74ALS623A, SN74AS623
OCTAL BUS TRANSCEIVERS
SDAS226A – DECEMBER 1982 – REVISED JANUARY 1995
PARAMETER MEASUREMENT INFORMATION
SERIES 54ALS/74ALS AND 54AS/74AS DEVICES
7V
RL = R1 = R2
VCC
S1
RL
R1
Test
Point
From Output
Under Test
CL
(see Note A)
From Output
Under Test
RL
Test
Point
From Output
Under Test
CL
(see Note A)
CL
(see Note A)
LOAD CIRCUIT FOR
BI-STATE
TOTEM-POLE OUTPUTS
LOAD CIRCUIT
FOR OPEN-COLLECTOR OUTPUTS
3.5 V
Timing
Input
Test
Point
LOAD CIRCUIT
FOR 3-STATE OUTPUTS
3.5 V
High-Level
Pulse
1.3 V
R2
1.3 V
1.3 V
0.3 V
0.3 V
tsu
Data
Input
tw
th
3.5 V
1.3 V
3.5 V
Low-Level
Pulse
1.3 V
0.3 V
1.3 V
0.3 V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
VOLTAGE WAVEFORMS
PULSE DURATIONS
3.5 V
Output
Control
(low-level
enabling)
1.3 V
1.3 V
0.3 V
tPZL
Waveform 1
S1 Closed
(see Note B)
tPLZ
[3.5 V
1.3 V
tPHZ
tPZH
Waveform 2
S1 Open
(see Note B)
1.3 V
VOL
0.3 V
VOH
1.3 V
0.3 V
[0 V
3.5 V
1.3 V
Input
1.3 V
0.3 V
tPHL
tPLH
VOH
In-Phase
Output
1.3 V
1.3 V
VOL
tPLH
tPHL
VOH
Out-of-Phase
Output
(see Note C)
1.3 V
1.3 V
VOL
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES, 3-STATE OUTPUTS
NOTES: A. CL includes probe and jig capacitance.
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, tr = tf = 2 ns, duty cycle = 50%.
E. The outputs are measured one at a time with one transition per measurement.
Figure 1. Load Circuits and Voltage Waveforms
POST OFFICE BOX 655303
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9
PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
SN74ALS620ADW
ACTIVE
SOIC
DW
20
25
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
ALS620A
Samples
SN74ALS620AN
ACTIVE
PDIP
N
20
20
RoHS &
Non-Green
NIPDAU
N / A for Pkg Type
0 to 70
SN74ALS620AN
Samples
SN74ALS621A-1N
ACTIVE
PDIP
N
20
20
RoHS &
Non-Green
NIPDAU
N / A for Pkg Type
0 to 70
SN74ALS621A-1N
Samples
SN74ALS621ADW
ACTIVE
SOIC
DW
20
25
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
ALS621A
Samples
SN74ALS621AN
ACTIVE
PDIP
N
20
20
RoHS &
Non-Green
NIPDAU
N / A for Pkg Type
0 to 70
SN74ALS621AN
Samples
SN74ALS623ADW
ACTIVE
SOIC
DW
20
25
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
ALS623A
Samples
SN74ALS623AN
ACTIVE
PDIP
N
20
20
RoHS &
Non-Green
NIPDAU
N / A for Pkg Type
0 to 70
SN74ALS623AN
Samples
SN74ALS623ANSR
ACTIVE
SO
NS
20
2000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
ALS623A
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of