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SiriusHardware · 20th Nov 2022, 1:20 pm

The article makes this happy behaviour of the DM (National Semiconductor) devices out to be a distinct virtue of theirs - you would instinctively expect that if you had a 'dead' (unpowered) device sitting on your data lines you would be in for all sorts of trouble. It seems unlikely that pin compatible devices from other manufacturers (AMD, Philips/Signetics, Tesla) would behave in such a similarly convenient fashion, but it may be worth reading up on.

To be honest I don't know which is the more damaging, to keep them powered on - Bipolar PROMs which are working perfectly normally run alarmingly hot and you have to think that can't do them any good in the long run, but on the other hand it's often the case that if a device is going to fail it is at the point of power-on, so powering them on thousands of times a second doesn't seem like a good idea either.

I do wish there was a pin compatible low-power modern equivalent which we could just drop in instead.

20th Nov 2022, 1:20 pm	#23
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,587	Re: MK14 SN74S571 PROM Power reduction test The article makes this happy behaviour of the DM (National Semiconductor) devices out to be a distinct virtue of theirs - you would instinctively expect that if you had a 'dead' (unpowered) device sitting on your data lines you would be in for all sorts of trouble. It seems unlikely that pin compatible devices from other manufacturers (AMD, Philips/Signetics, Tesla) would behave in such a similarly convenient fashion, but it may be worth reading up on. To be honest I don't know which is the more damaging, to keep them powered on - Bipolar PROMs which are working perfectly normally run alarmingly hot and you have to think that can't do them any good in the long run, but on the other hand it's often the case that if a device is going to fail it is at the point of power-on, so powering them on thousands of times a second doesn't seem like a good idea either. I do wish there was a pin compatible low-power modern equivalent which we could just drop in instead.