topic Re: High Temperature Application in 8-bit Microcontrollers

High Temperature Application

mikefr — Fri, 13 Apr 2007 11:41:24 GMT

Forum,

I am searching for an HCS08 part, that has a history of operating at 165 degrees Centigrade.

Anyone had any success with a HCS08 at this temperature ????

Thanks,

MikeF

Re: High Temperature Application

Alban — Fri, 13 Apr 2007 16:43:46 GMT

Hi Mike,

165°C is well above the maximum junction temperature they currently support: 135°C.
And that 135°C is supporting without damage, it is not under normally operating conditions above 125°C.

I think you need to wait for new special high temperature designs, if you wish to use an S08.

Alban.

Re: High Temperature Application

mikefr — Fri, 13 Apr 2007 22:53:26 GMT

This is above the recommended, but we use sevel uC which are rated at 125 degC, in a 180 degC environment. We just have no history with the HCS08 at this temperature.

We use HC11 @ elevetated temp's.

---Mike

Re: High Temperature Application

Curt — Sat, 14 Apr 2007 02:06:09 GMT

Hi mikefr

A design that runs a 125C part at 180C would be on "thin ice" indeed

In testing parts at elevated temps (_not_ Freescale's, so can't speak for them), a fairly common result is a gradual increase in die leakage currents until catastrophic failure occurs. This happens sooner rather than later.

So this makes the question not "will it work at 180C" -- but "how long will it work at 180C," and the answer is usually "not very long."

Hope your equipment isn't going into commercial aircraft -- is it?