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Details, datasheet, quote on part number:SN74ALS1245A-1
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Datasheet text preview:
SN54ALS1245A, SN74ALS1245A OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS
SDAS245A DECEMBER 1982 REVISED JANUARY 1995
· · · ·
Bidirectional Bus Transceivers in High-Density 20-Pin Packages Low-Power Versions of ALS245 Series ALS1245 Series Is Identical to ALS1645 Series Package Options Include Plastic Small-Outline (DW) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs
SN54ALS1245A . . . J PACKAGE SN74ALS1245A . . . DW OR N PACKAGE (TOP VIEW)
description
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 on the logic level at the directioncontrol (DIR) input. The output-enable (OE) input can be used to disable the device so the buses are effectively isolated. The SN54ALS1245A is characterized for operation over the full military temperature range of 55°C to 125°C. The SN74ALS1245A is characterized for operation from 0°C to 70°C.
FUNCTION TABLE INPUTS OE L L H DIR L H X OPERATION B data to A bus A data to B bus Isolation
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
SN54ALS1245A . . . FK PACKAGE (TOP VIEW)
A2 A1 DIR VCC OE A3 A4 A5 A6 A7
4 5 6 7 8 3 2 1 20 19 18 17 16 15 14 9 10 11 12 13
B1 B2 B3 B4 B5
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
A8 GND B8 B7 B6
Copyright © 1995, Texas Instruments Incorporated
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SN54ALS1245A, SN74ALS1245A OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS
SDAS245A DECEMBER 1982 REVISED JANUARY 1995
logic symbol
OE DIR 19 1 G3 3EN1 [BA] 3EN2 [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 18
logic diagram (positive logic)
19 OE
A1
2
DIR B1 A1
1
2
18
B1
To Seven Other Transceivers
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
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: SN54ALS1245A . . . . . . . . . . . . . . . . . . . . . . . . . . 55°C to 125°C SN74ALS1245A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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
SN54ALS1245A MIN VCC VIH VIL IOH IOL TA Supply voltage High-level input voltage Low-level input voltage High-level output current Low-level output current Operating free-air temperature 55 4.5 2 0.7 12 8 125 0 NOM 5 MAX 5.5 SN74ALS1245A MIN 4.5 2 0.8 15 16 70 NOM 5 MAX 5.5 UNIT V V V mA mA °C
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POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
SN54ALS1245A, SN74ALS1245A OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS
SDAS245A DECEMBER 1982 REVISED JANUARY 1995
electrical characteristics over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER VIK TEST CONDITIONS CONDITIONS VCC = 4.5 V, VCC = 4.5 V to 5.5 V, VCC = 4.5 V II = 18 mA IOH = 0.4 mA IOH = 3 mA IOH = 12 mA IOH = 15 mA IOL= 8 mA IOL = 16 mA VI = 7 V VI = 5.5 V VI = 2 7 V 2.7 VI = 0 4 V 0.4 VO = 2.25 V Outputs high Outputs low Outputs disabled 20 21 23 25 MIN SN54ALS1245A TYP MAX 1.5 VCC 2 2.4 2 2 0.25 0.4 0.1 0.1 20 20 0.1 0.1 112 33 36 40 30 21 23 25 0.25 0.35 0.4 0.5 0.1 0.1 20 20 0.1 0.1 112 30 33 36 mA V mA µA mA mA 3.2 VCC 2 2.4 3.2 MIN SN74ALS1245A TYP MAX 1.5 UNIT V
VOH
V
VOL II IIH IIL IO§ ICC Control inputs A or B ports Control inputs A or B ports Control inputs A or B ports
VCC = 4 5 V 4.5 VCC = 5 5 V 5.5 VCC = 5 5 V 5.5 V, VCC = 5 5 V 5.5 V, VCC = 5.5 V, VCC = 5.5 V
All typical values are 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.
switching characteristics (see Figure 1)
VCC = 4.5 V to 5.5 V, CL = 50 pF, R1 = 500 , R2 = 500 , TA = MIN to MAX¶ SN54ALS1245A SN74ALS1245A MIN tPLH tPHL tPZH tPZL tPHZ tPLZ A or B or B or A or A or B or A or B or 2 2 8 8 2 3 MAX 19 15 30 29 14 30 MIN 2 2 8 8 2 3 MAX 13 13 25 25 12 18 ns ns ns
PARAMETER
FROM (INPUT)
TO (OUTPUT)
UNIT
OE OE
¶ For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
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