SN74ALS990

八路 D 类透明读回锁存器

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.

The eight latches are transparent D-type latches. While the latch-enable LE input is high, the Q outputs follow the data D inputs.

Read back is provided through the output-enable input. When is taken low, the data present at the output of the data latches is allowed to pass back onto the input data bus. When is taken high, the output of the data latches is isolated from the D inputs. does not affect the internal operation of the latches; however, precautions should be taken not to create a bus conflict.

The is characterized for operation from 0°C to 70°C.

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3-State I/O-Type Read-Back Inputs

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Bus-Structured Pinout

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True Logic Outputs

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Package Options Include Plastic Small-Outline DW Packages and Standard Plastic N 300-mil DIPs