Bob Johnson (@Bob11)

Thirty years of design engineering in the broadcasting market designing audio and video products for TV, film, and post-production professionals. Programming from 6502s and 56001 DSPs to multi-core processors and Sharcs, board layout from Bishop Graphics tape to many-layer CAD, TTL to Zynq circuit designs, it's been a wild ride.

Re: Very low op voltage low current SMPS

Reply posted 3 years ago (10/11/2021)
Ah yes, it seems I completely misread the OP--his goal is to drive the movement itself directly. Sorry about that.

Re: Very low op voltage low current SMPS

Reply posted 3 years ago (10/10/2021)
Couldn't you just put another 10K resistor in series with the meter? That would basically cut the current in half and make it a 0 to 20V meter.

Re: motorola HC05 mask sets

Reply posted 3 years ago (10/01/2021)
I'm familiar with the 68HC05 from many many moons ago, but not this specific part. The only way to know for sure is to contact the manufacturer (Freescale/NXP?)...


Reply posted 3 years ago (04/25/2021)
You haven't given us much to go on. There's no guarantee the circuit you built looks like the circuit you drew. No reflection on you--a number of mine don't either....

Re: Audio system - wrong caps installed at factory?

Reply posted 3 years ago (03/04/2021)
What voltage are you seeing across the similar caps on the other channels? It appears from the circuit that the cap doesn't typically see much voltage across it....
A zener diode is usually used for voltage regulation. All you need is reverse blocking (of 12V), and minimum forward voltage drop (from 5V). A Schottky diode with...
You don't say exactly what you're trying to do. I presume you're trying to raise a logic/programming line to +12V to program an EEPROM.If that's the case, you can...

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