Joerg,
I've a 1A output current linear amplifier with a mosfet output stage where the supply voltage is servoed 1V above/below the output voltage.
Question: do you know of a better mosfet (with lower rdson) that will lower the power dissipation...
Hey, not my question but rather the one that my customer's young analog "specialist" dared to ask.
Pretty sad times...
-- Thanks, Fred.
Indeed! It's also ironic, in that a modern low Rds(on) mosfet may well have a smaller die and therefore a higher Rth_JC than the present part, and be worse for the job.
Unless, he's really thinking of lowering your 1V servod value, and figures a lower Rds(on) part would help make that work, that would be a reason for such a question.
A more current-capable mosfet would likely have higher transconductance at your 1A operating current, because it'd be closer to subthreshold operation.
--
Thanks,
- Win
AGM versus flooded batteries have different charge voltages and temperature compensation profiles (according to xantrex)
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I really really doubt that you could pull 600 W out of the 12 V output for more than a second or two before: sizzle, stink, pop pop, big stink, breaker trips.
=20
and=20
down.
The very winding on the transformer won't take it either.
Sorry for the late reply, was on a business trip.
A fast amplifier where the output is dynamically adjusted to the need? That only gets the heat off the chip and sinks it elsewhere, at the FETs. There's plenty of those, I'd tell your friend to check EU-stock because I don't know what you guys an buy or not. IRF would be a good place to start, or Vishay.
Yeah, you'd think he'd figure this stuff out on his own :-)
If he wants to really get rid of some dissipation he'd have to servo with two switchers. Or do class-D and forget the servo.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Install an ice cube dispenser above it :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
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