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''SIMM=Single Inline Memory Module''
[[Image:Crucial_72-pinSIMM.png|thumb|72 pin SIMM]]

Usually found in Intel 486 and Pentium computers.

{|
| '''Bits'''    || 32 bit or 36 bit (32+4 parity)
|-
| '''Speed'''   || 60ns to 70ns
|-
| '''Size'''    || 256kB to 4MB
|-
| '''Voltage''' || 3.3VDC or 5VDC
|}

Fast Page Mode (FPM) and Extended Data Out (EDO).

== Pinout ==

[[Image:simm72m.png]]

72 PIN SIMM at the computer.

{| {{border}}
! Pin !! Non-Parity !! Parity !! Description
|-
| 1   || VSS        || VSS    || Ground
|-
| 2   || DQ0        || DQ0    || Data 0
|-
| 3   || DQ16       || DQ16   || Data 16
|-
| 4   || DQ1        || DQ1    || Data 1
|-
| 5   || DQ17       || DQ17   || Data 17
|-
| 6   || DQ2        || DQ2    || Data 2
|-
| 7   || DQ18       || DQ18   || Data 18
|-
| 8   || DQ3        || DQ3    || Data 3
|-
| 9   || DQ19       || DQ19   || Data 19
|-
| 10  || VCC        || VCC    || +5 VDC
|-
| 11  || n/c        || n/c    || Not connected
|-
| 12  || A0         || A0     || Address 0
|-
| 13  || A1         || A1     || Address 1
|-
| 14  || A2         || A2     || Address 2
|-
| 15  || A3         || A3     || Address 3
|-
| 16  || A4         || A4     || Address 4
|-
| 17  || A5         || A5     || Address 5
|-
| 18  || A6         || A6     || Address 6
|-
| 19  || A10        || A10    || Address 10
|-
| 20  || DQ4        || DQ4    || Data 4
|-
| 21  || DQ20       || DQ20   || Data 20
|-
| 22  || DQ5        || DQ5    || Data 5
|-
| 23  || DQ21       || DQ21   || Data 21
|-
| 24  || DQ6        || DQ6    || Data 6
|-
| 25  || DQ22       || DQ22   || Data 22
|-
| 26  || DQ7        || DQ7    || Data 7
|-
| 27  || DQ23       || DQ23   || Data 23
|-
| 28  || A7         || A7     || Address 7
|-
| 29  || A11        || A11    || Address 11
|-
| 30  || VCC        || VCC    || +5 VDC
|-
| 31  || A8         || A8     || Address 8
|-
| 32  || A9         || A9     || Address 9
|-
| 33  || /RAS3      || /RAS3  || Row Address Strobe 3
|-
| 34  || /RAS2      || /RAS2  || Row Address Strobe 2
|-
| 35  || n/c        || PQ3    || Parity bit 3 (for the 3rd byte, bits 16-23)
|-
| 36  || n/c        || PQ1    || Parity bit 1 (for the 1st byte, bits 0-7)
|-
| 37  || n/c        || PQ2    || Parity bit 2 (for the 2nd byte, bits 8-15)
|-
| 38  || n/c        || PQ4    || Parity bit 4 (for the 4th byte, bits 24-31)
|-
| 39  || VSS        || VSS    || Ground
|-
| 40  || /CAS0      || /CAS0  || Column Address Strobe 0
|-
| 41  || /CAS2      || /CAS2  || Column Address Strobe 2
|-
| 42  || /CAS3      || /CAS3  || Column Address Strobe 3
|-
| 43  || /CAS1      || /CAS1  || Column Address Strobe 1
|-
| 44  || /RAS0      || /RAS0  || Row Address Strobe 0
|-
| 45  || /RAS1      || /RAS1  || Row Address Strobe 1
|-
| 46  || n/c  / A12  || n/c    || Not connected / Address 12*
|-
| 47  || /WE        || /WE    || Read/Write
|-
| 48  || n/c        || n/c    || Not connected
|-
| 49  || DQ8        || DQ8    || Data 8
|-
| 50  || DQ24       || DQ24   || Data 24
|-
| 51  || DQ9        || DQ9    || Data 9
|-
| 52  || DQ25       || DQ25   || Data 25
|-
| 53  || DQ10       || DQ10   || Data 10
|-
| 54  || DQ26       || DQ26   || Data 26
|-
| 55  || DQ11       || DQ11   || Data 11
|-
| 56  || DQ27       || DQ27   || Data 27
|-
| 57  || DQ12       || DQ12   || Data 12
|-
| 58  || DQ28       || DQ28   || Data 28
|-
| 59  || VCC        || VCC    || +5 VDC
|-
| 60  || DQ29       || DQ29   || Data 29
|-
| 61  || DQ13       || DQ13   || Data 13
|-
| 62  || DQ30       || DQ30   || Data 30
|-
| 63  || DQ14       || DQ14   || Data 14
|-
| 64  || DQ31       || DQ31   || Data 31
|-
| 65  || DQ15       || DQ15   || Data 15
|-
| 66  || n/c        || n/c    || Not connected
|-
| 67  || PD1        || PD1    || Presence Detect 1
|-
| 68  || PD2        || PD2    || Presence Detect 2
|-
| 69  || PD3        || PD3    || Presence Detect 3
|-
| 70  || PD4        || PD4    || Presence Detect 4
|-
| 71  || n/c        || n/c    || Not connected
|-
| 72  || VSS        || VSS    || Ground
|}

=== Size: ===

{| {{border}}
! PD2 !! PD1 !! Size
|-
| GND || GND || 4 or 64 MB
|-
| GND || NC  || 2 or 32 MB
|-
| NC  || GND || 1 or 16 MB
|-
| NC  || NC  || 8 MB
|}

=== Accesstime: ===

{| {{border}}
! PD4 !! PD3 !! Accesstime
|-
| GND || GND || 50, 100 ns
|-
| GND || NC  || 80 ns
|-
| NC  || GND || 70 ns
|-
| NC  || NC  || 60 ns
|}

''Notes:''
* ''Pin 32 (A9) is a N/C on 256k and 512k modules.''
* ''Pin 19 (A10) is a N/C on 256k, 512k, 1M and 4M modules.''
* ''Pin 46 is A12 on some 64MB modules, e.g. using Samsung K4F640411C chips.''
* ''Pin 45/33 (RAS1/RAS3) are N/C on 256k, 1M and 4M modules.''

== Contributions ==
* [[User:Joakim|Joakim Ögren]]
* [mailto:bugman@total.net Mark Brown]
* [mailto:Karsten.Wenke@t-online.de Karsten Wenke]
* [http://www.soyo.com.tw SOYO Computer Inc]
* Frédéric Pécourt

== Sources ==
* Various productsheets at [http://www.chips.ibm.com/products/memory/ IBM Memory Products]

[[Category:Connector]]
[[Category:Memory]]