CD74HC157

高速 CMOS 逻辑四路 2 输入多路复用器

The ’HC157, ’HCT157, ’HC158, and ’HCT158 are quad 2-input multiplexers which select four bits of data from two sources under the control of a common Select input S. The Enable input E\\ is active Low. When E\\ is High, all of the outputs in the 158, the inverting type, 1Y\\-4Y\\ are forced High and in the 157, the non-inverting type, all of the outputs 1Y\\-4Y\\ are forced Low, regardless of all other input conditions.

Moving data from two groups of registers to four common output busses is a common use of these devices. The state of the Select input determines the particular register from which the data comes. They can also be used as function generators.

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Common Select Inputs

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Separate Enable Inputs

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Buffered inputs and Outputs

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Fanout Over Temperature Range

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Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads

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Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads

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Wide Operating Temperature Range . . . -55°C to 125°C

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Balanced Propagation Delay and Transition Times

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Significant Power Reduction Compared to LSTTL Logic ICs

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HC Types

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2V to 6V Operation

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High Noise Immunity: NIL = 30%, NIH = 30%of VCC at VCC = 5V

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HCT Types

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4.5V to 5.5V Operation

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Direct LSTTL Input Logic Compatibility, VIL = 0.8V Max, VIH = 2V Min

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CMOS Input Compatibility, Il 1µA at VOL, VOH

The CD54HC158 and CD74HC158 are obsolete and no longer are supplied.