Using two 9v alkaline batteries in series for testing. Getting 18.5v. Single BUF634s at all positions. AD8610/8620 for OPAG/OPALR. IG to 8610 pin 7 (V+) = 8v. IG to 8620 pin 8 (V+) = 9.24v. Current sources installed. IG to 8620 pin 1 (OUTA) = 8.93v. IG to 8620 pin 7 (OUTB) = 8.68v. IG to 8620 pins 2, 3, 5 & 6 = 7.6v (should be 0, shouldn't it?). IG to 8620 pin 4 = -9.16v. With BUF643s installed, IG to BUFL & BUFR pins 6 = 8.0v. IG to BUFG pin 6 = 7.72v. IG to OL = 7.95v. IG to OR = 7.92v. IG to OG = 7.68v. IG to BUFG pin 7 (V+) = 8.95v. IG to BUFG pin 4 (V-) = -8.94v. 8610 pin 4 (V-) to pin 7 (V+) = 18.6v. 8620 pin 4 (V-) to pin 8 (V+) = 18.03v. OG to OR = 259mV. OG to OL = 266.5mV. Board was cleaned when each component was installed and I have used a magnifying glass, and continuity check on DMM, to validate solder joints. Nothing seems to get warm. Any ideas? 8620 done?
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2/21/07 at 1:42am