[sdiy] 3340 oscillator - current limiting resistor equation is wrong?

[Tom Wiltshire]

The 3340 VCO needs a current-limiting resistor on it’s negative supply if that supply is greater than -5 volts. The example data sheet circuit shows a -15V supply with a 820R resistor.

The data sheet also offers an equation for working out the resistor for other supply voltages:

	Ree = (Vee - 7.2) / 0.008

Which is the same as:

	Ree = (Vee - 7.2) * 125

(From http://www.curtiselectromusic.com/uploads/CEM_3340-3345_Long.pdf )

Now, here’s the funny bit. If you put -15V into that equation, you don’t get 820R.

	Ree = (15 - 7.2) * 125 = 7.8 * 125 = 975R

So what’s going on? Am I having a bad maths moment or missing something else, or is it just wrong?

Thanks,
Tom

==================
       Electric Druid
Synth & Stompbox DIY
==================