Oh, yeah, Don Lancaster has some REALLY interesting stuff he did a few years ago. he called it "magic sine waves". It is mostly a scheme for storing families of waves in EPROMS to synthesize sine waves with the minimum number of transitions (less transitions = less energy loss in the power transistors). The scheme stores just a single-bit sequence in the EPROM for every combination of frequency and voltage.
Jon
That sounds interesting, push pull power block driven with magic sine waves. Gotta give it a try down the road.
Best Regards Tom.
Thanks and good Luck, Bob
I visit IR on a regular basis, in particular i like thier app notes on mosfet push-pull designs. Seems that it may be possible to generate sine waves of sufficiant power to drive small motors. I will be experimenting with that concept down the road. Microchip also has some usefull app notes.
Best Regards Tom.
well, I for one would be astounded if a commercial notebook running windows or linux could keep up with the required IO for this task- start by deciding what your refresh rate for the waveform is - the waveform itself will be somewhere below 400 hz, but you will want to sample current and voltage and calcuate what to do at maybe 40 khz to 400 khz - how will you do that on a machine whose basic "fast" interrupt is 1.8 ms?
The computer will not have to sample voltage or current if i decide to interface to a IR2130. Proportional voltage current controll is a function of the IR2130 so i dont need a fast interrupt.
Best Regards Tom.
When the amount you've spent on destroyed power transistors approaches about 2/3 the cost of a new VFD, it's time to bale. Don't ask how I know....
G) Keep the spouse/kids/pets out of the lab when powering it up.
H) Show the spouse how to cut off the power quickly if you start screaming "cut off the power"
I) Don't underestimate the danger of a plasma fire.
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