gene glick wrote: > Some recent work at my day job involved 400 MHz opamps. These things > require careful layout to keep from oscillating, just as you say.
At my day-job we almost automatically choose MMIC amplifiers whenever amplification at frequencies beyond 100 MHz is required. Some of these little critters come with a data sheet saying "unconditionally stable" :-) Two weeks ago, a PHD student managed to detect 6.2 GHz with a Photo diode amplified by the fastest MMIC we could get from Farnell. The signal was produced by the beat note of two spectroscopically stabilized lasers. So she knew for sure, that the desired frequency was present. There was nothing special about the two layer layout. Just all HF components as close as possible and as much GND as would fit. In particular, no realistic 3D modeling and simulation of the fields was done. Still, it worked. :^) ---<(kaimartin)>--- -- Kai-Martin Knaak Öffentlicher PGP-Schlüssel: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x6C0B9F53 _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user