74157: Difference between revisions
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(they're not so "independent" if they share one select line) |
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The '''74157''' (variants 74LS157, 74HC157) is a 74-series logic IC with four 2-input multiplexers sharing a single select line. | The '''74157''' (variants 74LS157, 74HC157) is a 74-series logic IC with four 2-input multiplexers sharing a single select line. | ||
== 74157 Pinout == | == 74157 Pinout == | ||
.--\/--. | |||
S -> |01 16| -- +5V | |||
1I0 -> |02 15| <- /E | |||
1I0 - |02 15| - /E | 1I1 -> |03 14| <- 4I0 | ||
1I1 - |03 14| - 4I0 | 1Y <- |04 13| <- 4I1 | ||
2I0 -> |05 12| -> 4Y | |||
2I0 - |05 12| - 4Y | 2I1 -> |06 11| <- 3I0 | ||
2I1 - |06 11| - 3I0 | 2Y <- |07 10| <- 3I1 | ||
Gnd -- |08 09| -> 3Y | |||
Gnd - |08 09| - 3Y | `------' | ||
== Signal descriptions == | == Signal descriptions == | ||
If /E is high, then all 4 Y output pins output as low, otherwise, if S is low, for each set of pins starting with the same number, Y is equal to I0, otherwise, if S is high, then Y is equal to I1. | If /E is high, then all 4 Y output pins output as low, otherwise, if S is low, for each set of pins starting with the same number, Y is equal to I0, otherwise, if S is high, then Y is equal to I1. | ||
[[Category:7400 series|157]] | [[Category:7400 series|157]] | ||
Revision as of 04:24, 31 January 2013
The 74157 (variants 74LS157, 74HC157) is a 74-series logic IC with four 2-input multiplexers sharing a single select line.
74157 Pinout
.--\/--.
S -> |01 16| -- +5V
1I0 -> |02 15| <- /E
1I1 -> |03 14| <- 4I0
1Y <- |04 13| <- 4I1
2I0 -> |05 12| -> 4Y
2I1 -> |06 11| <- 3I0
2Y <- |07 10| <- 3I1
Gnd -- |08 09| -> 3Y
`------'
Signal descriptions
If /E is high, then all 4 Y output pins output as low, otherwise, if S is low, for each set of pins starting with the same number, Y is equal to I0, otherwise, if S is high, then Y is equal to I1.
