MC3340 or RS 306-803

[ppppenguin]

I've found a few RS 306-803. This RS data sheets says they are electronic attenuators: http://archive.retro.co.za/archive/datas...nuator.pdf

I had a gut feeling they might be Motorola MC3340: http://www.applelogic.org/files/MC3340.pdf

I tried scraping the RS paint and markings off one but not quite carefully enough to be able to read the original markings.

What do people think?

[radioman]

Yes, spot-on Jeffrey - I've got the RS datasheet library and the index lists sheet 2983 for the MC3340P.

Andy

[ppppenguin]

Thanks, Andy.

I wonder if anyone has digitised the RS data library. I used to have a load of the sheets but heaven knows where they are now.

[radioman]

I've got two versions of them (somewhere...)
Scanning would be a mammoth task.... however, I can do this on a needs basis for single sheets.
Funnily enough, most of them are not for electronic components.

Andy

[ppppenguin]

The RS 2983 scan that I linked to is presumably the same as your paper copy. Nowhere does it explicitly say that the chip is a MC3340 in disguise. That was back in the days when RS sold everything udner their own name. It took a while for them to realise that hiding the original manufacturer ID was not a good idea.

I suppose that philiosphy dates back to the time when Radiospares (as it then was) didn't sell valves, transistors or chips at all.

[radioman]

The actual datasheet I've got is the same as the scan you linked to and as you say, it isn't mentioned that it's a MC3340 on the sheet - however, the index does list it.

Andy

[ppppenguin]

I've just found my RS data library. Sheet 12328 is a list of manufacturers' part numbers with RS stock numbers. MC3340P is indeed 306-803. Sheet 10710 is a contents list and seminconductor device type index. This references the MC3340P to sheet 2983. I also have an earlier index/cross reference 7720 and a some even earlier data library indexes.

A lot of the earlier sheets give the old Epworth Street address in The City of London.

The whole lot is about 2" thick in a big ring binder. It was hidden in an obscure corner of my bookshelves.

[Mike Watterson]

I wonder if anyone has digitised the RS data library. I used to have a load of the sheets but heaven knows where they are now.

I've a load of RS CDs somewhere, different years, some certainly have data sheets. I remember buying MC3340 ages ago. A few years ago I bought some Philips attenuators controlled by I2C, intending to add them to a PIC programmed in JAL. Still in the drawer unused.