|
Details, datasheet, quote on part number:SN74ALS642A-1DWR
| |
Datasheet text preview:
SN74ALS641A, SN74ALS642A, SN74AS641 OCTAL BUS TRANSCEIVERS WITH OPEN-COLLECTOR OUTPUTS
SDAS300 MARCH 1995
· · ·
Bidirectional Bus Transceivers in High-Density 20-Pin Packages Choice of True or Inverting Logic Package Options Include Plastic Small-Outline (DW) Packages and Standard Plastic (N) 300-mil DIPs
DEVICE SN74ALS641A, SN74AS641 SN74ALS642A LOGIC True Inverting
DW OR N PACKAGE (TOP VIEW)
description
DIR A1 A2 A3 A4 A5 A6 A7 A8 GND
1 2 3 4 5 6 7 8 9 10
20 19 18 17 16 15 14 13 12 11
VCC OE B1 B2 B3 B4 B5 B6 B7 B8
These octal bus transceivers are designed for asynchronous two-way communication between data buses. These devices transmit data from the A bus to the B bus or from the B bus to the A bus, depending upon the level at the direction-control (DIR) input. The output-enable (OE) input disables the device so that the buses are effectively isolated. The -1 versions of the SN74ALS641A and SN74ALS642A are identical to the standard versions, except that the recommended maximum IOL is increased to 48 mA in the -1 versions. The SN74ALS641A, SN74ALS642A, and SN74AS641 are characterized for operation from 0°C to 70°C.
FUNCTION TABLE INPUTS OE L L H DIR L H X OPERATION SN74ALS641A SN74AS641 B data to A bus A data to B bus Isolation SN74ALS642A B data to A bus A data to B bus Isolation
logic symbols
SN74ALS641A, SN74AS641 OE DIR 19 1 G3 3 EN1 [BA] 3 EN2 [AB] 1 2 A2 A3 A4 A5 A6 A7 A8 3 4 5 6 7 8 9 17 16 15 14 13 12 11 B2 B3 B4 B5 B6 B7 B8 A2 A3 A4 A5 A6 A7 A8 3 4 5 6 7 8 9 18 B1 OE DIR 19 1 SN74ALS642A G3 3 EN1 [BA] 3 EN2 [AB] 1 2 17 16 15 14 13 12 11 B2 B3 B4 B5 B6 B7 B8 18 B1
A1
2
A1
2
These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
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.
Copyright © 1995, Texas Instruments Incorporated
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
1
SN74ALS641A, SN74ALS642A, SN74AS641 OCTAL BUS TRANSCEIVERS WITH OPEN-COLLECTOR OUTPUTS
SDAS300 MARCH 1995
logic diagrams (positive logic)
SN74ALS641A, SN74AS641 OE 19 OE 19 SN74ALS642A
DIR
1
DIR
1
A1
2
18
B1 A1
2
18
B1
To Seven Other Transceivers
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 and I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V Operating free-air temperature range, TA: SN74ALS641A, SN74ALS642A . . . . . . . . . . . . . . . . . 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
SN74ALS641A SN74ALS642A MIN VCC VIH VIL VOH IOL Supply voltage High-level input voltage Low-level input voltage High-level output voltage Low-level output current output current 0 4.5 2 0.8 5.5 24 48 70 NOM 5 MAX 5.5 V V V V mA °C UNIT
TA Operating free-air temperature Applies only to the -1 version and only if VCC is between 4.75 V and 5.25 V
2
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
SN74ALS641A, SN74ALS642A, SN74AS641 OCTAL BUS TRANSCEIVERS WITH OPEN-COLLECTOR OUTPUTS
SDAS300 MARCH 1995
electrical characteristics over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER VIK IOH VOL II IIH IIL Control inputs Control inputs A or B ports§ Control inputs A or B ports§ SN74ALS641A ICC SN74ALS642A VCC = 5 5 V 5.5 TEST CONDITIONS VCC = 4.5 V, VCC = 4.5 V, VCC = 4.5 V VCC = 5.5 V, VCC = 5 5 V 5.5 V, VCC = 5 5 V 5.5 V, VCC = 5 5 V 5.5 II = 18 mA VOH = 5.5 V IOL = 12 mA IOL = 24 mA IOL = 48 mA VI = 7 V VI = 2 7 V 2.7 VI = 0 4 V 0.4 Outputs high Outputs low Outputs high 25 33 8 18 0.25 0.35 0.35 SN74ALS641A SN74ALS642A MIN TYP MAX 1.5 0.1 0.4 0.5 0.5 0.1 20 20 0.1 0.1 37 47 15 28 mA mA µA mA V V mA UNIT
Outputs low 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)
VCC = 4.5 V to 5.5 V, CL = 50 pF, RL = 680 , TA = MIN to MAX¶ SN74ALS641A MIN tPLH tPHL tPLH tPHL tPLH tPHL A or B or 5 B or A or A or B or A or B or 3 8 OE DIR 8 8 8 MAX 25 18 30 30 32 32 SN74ALS642A MIN 10 5 10 15 10 15 MAX 30 22 30 38 30 38 ns ns ns
PARAMETER
FROM (INPUT)
TO (OUTPUT)
UNIT
¶ For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
3
|
|
