Once I got my TIC going, I suppose it was inevitable that I build a GPSDO with a dsPIC33. I have a few dsPIC specific questions for anyone who designs with them.
1. VCAP. The datasheet says that it should be a surface mount device. I had hoped to avoid those. Can I get away with a 10uf tantalum placed at .1" from the pin? I'm using a 28-pin DIP dsPIC, which will probably be socketed. 2. The datasheet suggests an inductor between AVDD and VDD. Given that I'll only be reading the ADC twice a second (PPS and temps), can I just use the straight wire that I have already penned in? I'm starting to run out of board space. As to why I'm using a dsPIC: the one I chose has a number of features that suit me, such as 2 UARTs, SPI, buffered ADC, (audio) DAC, and especially relocatable pins. To be honest, I don't know whether this will result in a general purpose GPSDO engine (with sawtooth correction) or a smoke machine, but I'm hoping for the best. I'll try to resist the temptation to make more posts until I have a completed project. Bob - AE6RV _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
