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SN74ALS990 8-BIT D-TYPE TRANSPARENT READ-BACK LATCH
SDAS027B – APRIL 1984 – REVISED JANUARY 1995
• 3-State I/O-Type Read-Back Inputs • Bus-Structured Pinout • True Logic Outputs • Package Options Include Plastic
Small-Outline (DW) Packages and Standard Plastic (N) 300-mil DIPs
description
This 8-bit latch is designed specifically for storing the contents of the input data bus and providing the capability of reading back the stored data onto the input data bus.
DW OR N PACKAGE (TOP VIEW)
OERB 1 1D 2 2D 3 3D 4 4D 5 5D 6 6D 7 7D 8 8D 9
GND 10
20 VCC 19 1Q 18 2Q 17 3Q 16 4Q 15 5Q 14 6Q 13 7Q 12 8Q 11 LE
The eight latches are transparent D-type latches. While the latch-enable (LE) input is high, the Q outputs follow the data (D) inputs.
SN74ALS990 Datasheet
