nikgr wrote on Oct 20th, 2012, 1:44am:So I saw the solution of frequency divider proposed by Ken Kundert for no hidden states, but it doesn't work neither because the output voltage is 0 volts.
Do you understand how that model is supposed to work? Have you tried debugging it? You can add lines like
$strobe("V(chg)=%d V(hold)=%g out=%g", V(chg), V(hold), out);
to see some of the internal workings.
A quick thought is: I noticed that Vdd=5 in his model, so if you're working with a 2.5V or lower supply, you'll never get above the threshold assumed by that model.