Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Paul and Sabrina's Cheap 3 Phase Inverter (AC Controller) with Field Oriented Control

MPaulHolmes · 07-11-2016, 04:51 PM

The only reason I like the attiny is, the very high impedance 62.5kHz signal is very short and never leaves the PCB, which has a ground plane running right under the high frequency signals. I've never had a problem getting the isolated supplies working using it. The dspic has a few interrupts running. Could it be that the 62.5kHz timer sometimes gets put on hold due to other interrupts? With the ATTiny It's an identical number of 1MHz cycles on as off at 1MHz. So, any variation would only be in the difference between turnoff and turnon time of ports. The inverter chip would work I bet, but I would just be worried that you would really have a perfectly consistent 62.5KHz signal due to interrupt issues. I know you could make the 62.5kHz timer the highest priority. maybe that could eliminate jitter.

07-11-2016, 04:51 PM	#2797 (permalink)
MPaulHolmes PaulH Join Date: Feb 2008 Location: Maricopa, AZ (sort of. Actually outside of town) Posts: 3,832 Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000 Thanks: 1,362 Thanked 1,202 Times in 765 Posts	The only reason I like the attiny is, the very high impedance 62.5kHz signal is very short and never leaves the PCB, which has a ground plane running right under the high frequency signals. I've never had a problem getting the isolated supplies working using it. The dspic has a few interrupts running. Could it be that the 62.5kHz timer sometimes gets put on hold due to other interrupts? With the ATTiny It's an identical number of 1MHz cycles on as off at 1MHz. So, any variation would only be in the difference between turnoff and turnon time of ports. The inverter chip would work I bet, but I would just be worried that you would really have a perfectly consistent 62.5KHz signal due to interrupt issues. I know you could make the 62.5kHz timer the highest priority. maybe that could eliminate jitter. __________________ kits and boards Last edited by MPaulHolmes; 07-11-2016 at 05:13 PM..