On Sat, 23 Feb 2002, Richard Atkinson wrote: > > I haven't heard of PMOS logic chips - but the hole mobility is about 2.5 > > times less than electron mobility and P-channel transistor should have ~2.5 > > times wider channel to have the same transconductance as N-channel one. So > > PMOS gates would simply be bigger... > > Or slower. In fact, generally not as good. Does anyone know of any PMOS > logic ICs? I was surprised to find out recently that the SN76489 DCSG used > in a number of old systems is in fact bipolar - current injection logic if > I'm not mistaken. Sorry to answer my own post but I learnt some things last night at Tony Duell's talk on HP calculators. Apparently most calculators from the HP35 until the Saturn processor series used a PMOS process. They made one in NMOS and another in CMOS, but all the early ones were PMOS. Richard Message was sent through the cbm-hackers mailing list
Archive generated by hypermail 2.1.1.