726 (time to change the subject line (;->) )

[terry michaels]

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