On Tue, 05 Oct 2004 03:47:13 +0000, NSM wrote:


"keith" wrote in message
news
| So do engineers when they're bringing up a system where all
| of the tantallums were inserted backwards. You want to see fireworks!
| (well,it was 25 years ago - I've mostly recovered and the tinninus
| isn't so bad. twitch)

I recall being told of a large TTL circuit board which was powered up with
reverse polarity. This was noticed due to the considerable amount of heat
being given off.

Everyone was mystified when the correctly rewired board worked OK. I guess
TTL is a little more tolerant than is generally believed.

TTL protection diodes are as strong as moose! Unless the chips got hot
enough to let the magic smoke out, they'll likely survive, though perhaps
somewhat injured.

--
Keith