74157: Difference between revisions

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(Created page with "The '''74157''' (variants 74LS32, 74HC157) is a 74-series logic IC with four independent 2-input multiplexers. == 7432 Pinout == <pre> .--\/--. S - |01 16| - +5V 1I0 ...")
 
 
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The '''74157''' (variants 74LS32, 74HC157) is a 74-series logic IC with four independent 2-input multiplexers.
The '''74157''' (variants 74LS157, 74HC157) is a 74-series logic IC with four 2-input multiplexers sharing a single select line.
== 7432 Pinout ==
== 74157 Pinout ==
<pre>
        .--\/--.
      .--\/--.
  S -> |01  16| -- +5V
  S - |01  16| - +5V
1I0 -> |02  15| <- /E
1I0 - |02  15| - /E
1I1 -> |03  14| <- 4I0
1I1 - |03  14| - 4I0
  1Y <- |04  13| <- 4I1
1Y - |04  13| - 4I1
2I0 -> |05  12| -> 4Y
2I0 - |05  12| - 4Y
2I1 -> |06  11| <- 3I0
2I1 - |06  11| - 3I0
  2Y <- |07  10| <- 3I1
2Y - |07  10| - 3I1
Gnd -- |08  09| -> 3Y
Gnd - |08  09| - 3Y
        `------'
      `------'</pre>
 
== 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.
Function table (L/H/X = low/high/irrelevant):
{| class="tabular" style="text-align:center;"
! /E !! S !! I0 !! I1 !! style="border-left:3px double" |Y
|-
| H || X || X || X || style="border-left:3px double" |L
|-
| L || L || L || X || style="border-left:3px double" |L
|-
| L || L || H || X || style="border-left:3px double" |H
|-
| L || H || X || L || style="border-left:3px double" |L
|-
| L || H || X || H || style="border-left:3px double" |H
|}
== References ==
* [https://www.ti.com/product/SN74LS157 TI - SN74LS157]
[[Category:7400 series|157]]
[[Category:7400 series|157]]

Latest revision as of 18:09, 16 April 2023

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.

Function table (L/H/X = low/high/irrelevant):

/E S I0 I1 Y
H X X X L
L L L X L
L L H X H
L H X L L
L H X H H

References