To: synth synth-diy@mailhost.bpa.nl,
From: terry michaels 104065.2340@compuserve.com,
cc:
Subject: 726 (time to change the subject line (;->) )
Date: Tue, 16 Feb 1999 08:11:19 -0500

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Message text written by Haible Juergen
>>I have an old Fairchild data book which lists the uA726 temperature
>controlled differential pair. I spotted two things of interest in
the date
>sheets. A graph of power dissipation for the chip heater vs
ambient
>temperature goes to zero dissipation when the ambient temperature
reaches
>97 degrees C, so I assume that is the chip temperature.

I think the 726's temperature could be programmed by an external resistor.
Your conclusion must be right, of course, but the diagram you refer to
might
be a typical courve for one chosen chip temperature.

I only have an uncomplete data sheet (2 pages), but it clearly shows
a temperature adjust pin. I'm almost sure that I have seen 726 circuits
with different resistor values, but I don't remember where.

Is there any additional information in the Fairchild book ?

JH.
<

Hi Juergen

You're absolutely right, the temperature is set with a resistor from pin 6
to ground. The graph I was referring to was for use of a 75K resistor.
There is a second graph showing a higher temperature, about 120 degrees C,
using a 62K resistor.

180 milliwatts seems to ba a lot of heat for a small metal IC package
(TO-100).

I'm glad you changed the subject line. I was too lazy.

Terry