CA3046,SSM2210&2220 Replacements

[Tim Ressel]

To all,

As you may have heard, I am investigating using a MAT04 from Analog Devices as
an exponential converter/heater. I did some advance work this weekend while I
wait for my samples. The MAT04 is spec'd at 30ma max, but the heater a la Nat
Semi peaks at about 85ma at startup. So a minor tweak fixes that. My approach is
to simply increase the collector resistor on the clamp transistor to about 91
ohms. Alternately you could fiddle the voltage divider on the base of the clamp
transistor.

All in all, the MAT 04 looks real good on paper. It has way better specs than
the 3046, and was meant for expo converters. Let us keep our fingers crossed.

The latest Digi-key catalog just arrived, and Lo! they now carry a line of dual
transistors from Panasonic! (July/September '99 page 225). There is a variety of
duals which seem to be based on the 2Sx type of devices. Check it out!

Timster