These devices are only suitable for driving source terminated 50 ohm transmission lines not a 50 ohm load to ground (or even 1/2Vcc) to produce CMOS levels at the load.
If you are driving a low pass filter or similar intending to produce a sinewave output then its somewhat easier. Even paralleling CMOS outputs won't produce quite a full CMOS swing across a 50 ohm load. The classical solution was to either double the swing and use both source and load termination or use the Thevenin equivalent using a switched current source. If AC coupling were allowed push pull drive of a 1:1 RF transformer from a pair of complementary 25 ohm Zout CMOS drivers would produce a full amplitude swing across a 50 ohm load, however some dc biasing would be required at the load to achieve CMOS levels. Bruce > > On 04 March 2018 at 15:17 "David C. Partridge" > <[email protected]> wrote: > > Brice said: > > > > > > . Some fast CMOS devices (esp clock drivers) have an output R close > > to 50 > > ohms as they are intended to drive 50 ohm source terminated > > transmission > > lines. > > > > > > Any in particular that you'd recommend? I need to drive a 50ohm line and a > single gate inverter doesn't have the grunt to do so ... > > Thanks > David > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
