I finally got a chance to fix the crystal-locked switching power supply sync circuit.
If you remember, the 12 MHz crystal was oscillating sinusoidally with Vpp = 1.5V and a DC offset of about 100 mV. I threw a 200 pF cap between the crystal and the 74LV163 binary counter's input, and then pulled up the input to 1/2 Vcc using 100K resistors. Worked like a charm. I was in a rush (shock) so I don't have performance measurements yet - hope to have that on Monday. This officially concludes all GFE operational testing. I'm going to go verify that all the fixes are in the schematic, and then officially tag that as ready to go for custom node5 boards. The first node5 board will be the APS, which Naga is ramping up on right now. Andrew -- ------------------------------------------------------- Andrew Greenberg Portland State Aerospace Society (http://psas.pdx.edu/) and...@psas.pdx.edu P: 503.788.1343 C: 503.708.7711 ------------------------------------------------------- _______________________________________________ psas-avionics mailing list psas-avionics@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-avionics
