That network was for a 10MHz input. For 5MHz double the L and C values.
For 3.3V one could use a lower step up say from 50 to 400 ohms rather than from 50 to 800 ohms. 1uH and 150pF and change 1k6 resistors to 820R. Swap the 5V supply for a 3.3V supply. L and C values aren't critical 5% or somewhat looser tolerance should be suffice. Bruce > > On 20 January 2018 at 14:14 Bruce Griffiths <bruce.griffi...@xtra.co.nz> > wrote: > > Something like the attached circuit is suitable for driving the MCU clock > input directly. > The diodes should be schottky signal diodes like the 1N5711 series. The > series resistors limit the diode peak current and the CLK input protection > network current. It should work with inputs from 1V pp to 8Vpp. If SMT > components were used it should all fit on a DIP compatible daughter board. > > Bruce > > > > > > On 20 January 2018 at 12:37 Bob kb8tq <kb...@n1k.org> wrote: > > > > Bob > > > > With a 1V p-p sort of output, a simple matching network will get > > you into the 4 to 6V p-p range. > > Drive that into a 5V compatible CMOS gate and move on …. If you > > have a super hot output, put > > a 3 db pad on it. > > > > Bob > > > > > > > > > > On Jan 19, 2018, at 5:40 PM, Tom Van Baak > > > <t...@leapsecond.com> wrote: > > > > > > > > > > > > > > Tom > > > > What's the input signal amplitude? > > > > What's the desired output signal (eg 5V CMOS, 3.3V CMOS > > > > etc)? > > > > Bruce > > > > > > > > > > > > > > It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave > > > output; say, 1 Vpp. The output should be 3.3 or 5 V depending on what the > > > MCU needs. It doesn't have to have stunning performance: think > > > breadboard, PIC, Arduino sort of stuff. I was looking for something in a > > > PDIP-8 package; the same as all the picDIV or picPET chips I use. That's > > > why older parts like µA9637 / DS9637 came to mind. > > > > > > /tvb > > > > > > _______________________________________________ > > > time-nuts mailing list -- time-nuts@febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions > > there._______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
