CPU and Integrated circuits around CPU

[tekno1]

Hello, I am an integrated circuit designer. I would like to know what CPU (uProcessors) are used in PLC's and what integrated circuits used around them. I check around for service manuals so that I could look into BOM and schematics but so far I did not have any luck. I want to know what integrated circuits are used in PLC industry and if possible their actual system level usage in PLC's. My purpose is to asses any possibility to integrate digital and analog functionality within CPU chip to reduce integrated circuit count. Latest models will be useful for determining state of the art. Any of Copy of service manuals, CPU and surrounding schematic, BOM or even clear pictures of boards could be useful. thanks in advance in any help.

[gravitar]

I was curious about that when I first got my hands on PLCs, too :) From what I recall, the A-B PLC 5's main CPU is a MC68020, with a Z-80 on each communication "plug". The older SLC 500 processors had an intel 80C32 (probably the micrologix 1000 too), can't remember what's on the newer ones. I remember hearing that the original PLC-2 was 8080-based, but I have't looked at one in a while. I also recall hearing that the original 1774 PLC was a modified minicomputer (HP?) but I've never been able to find one of those that I could get my hands on! The PLC-3 used an AMD bit-slice design. Not sure what the ControlLogix platform uses.. Edited April 12, 2007 by gravitar

[Ken Moore]

I don't understand Russian, but I believe this is the inside of an S7 from Siemens: http://s7detali.narod.ru/ I think the PLC-3 was an AMD 2901 or 2903 http://www.cpu-world.com/CPUs/2901/ I know the Texas Instruments PLC's used Motorola 68000 series chips