Re: ATM CCD overheat detect/shutdown circuit

[George Anderson <georgea@CAM.ORG>]

A regular silicon diode will give a response of 3.3mm/deg C. Just use an
op-amp to subtract the offset and then a second to multiply it to a
reasonable voltage. You should be able to go quite high in gain as
frequency should not be a problem.
Just use one in a glass case as the plastic cases slow the response down
a lot, alo light has a small effect on the output voltage.
George Anderson
Montreal Canada

Clear skies and good health

Leftfieldstar@aol.com wrote:
> 
> In a message dated 8/4/01 1:56:44 PM Eastern Daylight Time,
> pdbrooks@pacbell.net writes:
> 
> << There's a National Semi part that acts as a diode with a forward voltage =
>  10mV/degree K.  Tie one or more comparators to the output and you can a
> simple
>  interlock that can handle multiple options (warning light/buzzer, Peltier
>  interlock, CCD powerdown, et cetera).  Not sure of the part number, though.
>   >>
> I believe it is LM335. Go to
> :http://www.inetworld.net/clement/temp_control.html for a schematic employing
> it and some info sites on the active devices used in it.
> 
> Dominic DiLeo
> 
> Dominic DiLeo