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Details, datasheet, quote on part number:SN74ALS873BDWR
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Datasheet text preview:
SN54ALS873B, SN54AS873A, SN74ALS873B, SN74AS873A DUAL 4-BIT D-TYPE LATCHES WITH 3-STATE OUTPUTS
SDAS036D APRIL 1982 REVISED AUGUST 1995
· · ·
3-State Buffer-Type Outputs Drive Bus Lines Directly Bus-Structured Pinout Package Options Include Plastic Small-Outline (DW) Packages, Ceramic Chip Carriers (FK), and Plastic (NT) and Ceramic (JT) DIPs
SN54ALS873B, SN54AS873A . . . JT PACKAGE SN74ALS873B, SN74AS873A . . . DW OR NT PACKAGE (TOP VIEW)
description
These dual 4-bit D-type latches feature 3-state outputs designed specifically for bus driving. These devices are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers. The dual 4-bit latches are transparent D-type latches. While the latch-enable (LE) input is high, the Q outputs follow the data (D) inputs in true form, according to the function table. When LE is low, the outputs are latched. When the clear (CLR) input goes low, the Q outputs go low independently of LE. The outputs are in the high-impedance state when the output-enable (OE) input is at a high logic level. The SN54ALS873B and SN54AS873A are characterized for operation over the full military temperature range of 55°C to 125°C. The SN74ALS873B and SN74AS873A are characterized for operation from 0°C to 70°C.
1CLR 1OE 1D1 1D2 1D3 1D4 2D1 2D2 2D3 2D4 2OE GND
1 2 3 4 5 6 7 8 9 10 11 12
24 23 22 21 20 19 18 17 16 15 14 13
VC C 1LE 1Q1 1Q2 1Q3 1Q4 2Q1 2Q2 2Q3 2Q4 2LE 2CLR
SN54ALS873B, SN54AS873A . . . FK PACKAGE (TOP VIEW)
1D2 1D3 1D4 NC 2D1 2D2 2D3
1D1 1OE 1CLR NC VCC 1LE 1Q1
4 5 6 7 8 9 10 3 2 1 28 27 26 25 24 23 22 21 20 19 11 12 13 14 15 16 17 18
1Q2 1Q3 1Q4 NC 2Q1 2Q2 2Q3
NC No internal connection FUNCTION TABLE (each latch) INPUTS OE L L L L H CLR L H H H X LE X H H L X D X H L X X OUTPUT Q L H L Q0 Z
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
2D4 2OE GND NC 2CLR 2LE 2Q4
Copyright © 1995, Texas Instruments Incorporated
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SN54ALS873B, SN54AS873A, SN74ALS873B, SN74AS873A DUAL 4-BIT D-TYPE LATCHES WITH 3-STATE OUTPUTS
SDAS036D APRIL 1982 REVISED AUGUST 1995
logic symbol
2 1OE 1LE 1CLR 1D1 1D2 1D3 1D4 3 4 5 6 23 1 EN C1 C 1D 22 21 20 19 1Q1 1Q2 1Q3 1Q4
logic diagram (each quad latch, positive logic)
OE
LE
CLR R C1 D1 1D R C1 D2 1D R C1 D3 1D Q1
11 2OE 2LE 2CLR 2D1 2D2 2D3 2D4 14 13 7 8 9 10
EN C1 C 1D 18 17 16 15 2Q1 2Q2 2Q3 2Q4 D4
Q2
Q3
R C1 1D
Q4
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12. 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, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V Input voltage, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V Voltage applied to a disabled 3-state output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V Operating free-air temperature range, TA: SN54ALS873B . . . . . . . . . . . . . . . . . . . . . . . . . . . 55°C to 125°C SN74ALS873B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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
SN54ALS873B 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 1 12 125 0 NOM 5 MAX 5.5 SN74ALS873B MIN 4.5 2 0.8 2.6 24 70 NOM 5 MAX 5.5 UNIT V V V mA mA °C
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POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
SN54ALS873B, SN54AS873A, SN74ALS873B, SN74AS873A DUAL 4-BIT D-TYPE LATCHES WITH 3-STATE OUTPUTS
SDAS036D APRIL 1982 REVISED AUGUST 1995
electrical characteristics over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER VIK VOH TEST CONDITIONS CONDITIONS VCC = 4.5 V, VCC = 4.5 V to 5.5 V, VCC = 4 5 V 4.5 VCC = 4 5 V 4.5 VCC = 5.5 V, VCC = 5.5 V, VCC = 5.5 V, VCC = 5.5 V, VCC = 5.5 V, VCC = 5.5 V, VCC = 5.5 V II = 18 mA IOH = 0.4 mA IOH = 1 mA IOH = 2.6 mA IOL = 12 mA IOL = 24 mA VO = 2.7 V VO = 0.4 V VI = 7 V VI = 2.7 V VI = 0.4 V VO = 2.25 V Outputs high ICC Outputs low 20 11 16 MIN SN54ALS873B TYP MAX 1.2 VCC 2 2.4 VCC 2 3.3 2.4 0.25 0.4 20 20 0.1 20 0.2 112 21 29 30 11 16 3.2 0.25 0.35 0.4 0.5 20 20 0.1 20 0.2 112 21 29 mA V µA µA mA µA mA mA V MIN SN74ALS873B TYP MAX 1.2 UNIT V
VOL IOZH IOZL II IIH IIL IO
Outputs disabled 20 31 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.
timing requirements over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (see Figure 1)
SN54ALS873B MIN tw tsu th Pulse duration duration Setup time, data before LE Hold time, data after LE CLR low LE high 15 10 10 7 MAX SN74ALS873B MIN 15 10 10 7 MAX UNIT ns ns ns
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
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