555 Timer
		Using the Texas Instruments TLC555 timer model as an oscillator requires the correct 5Spice settings. In the schematic, use a pullup resistor and an Initial Condition on the 555's Reset input. Otherwise the 555 does not start oscillating. Set the value of the Initial Condition to 0. (Explanation: An oscillator needs to be disturbed from its dc operating point in order to begin oscillating. We are using a pulse on the 555's reset input here. You could also use a Signal Source as the power supply and ramp the supply up from zero volts at the start of Transient analysis. Use a realistic risetime.) When setting up the analysis, select the FINE dynamic time step, select the Help box under Convergence Help, and enable Initial Conditions. Run Transient analysis and inspect the output waveform. If the oscillation is not stable, reduce the value of the Time Step in the analysis and run again. A simpler alternative to using the TLC555 model is the one-shot included as part of 5Spice version 1.20 and newer. You need to register the program to save schematic's with the 5Spice one-shot.