Dave's Circuits:  Frequency to Voltage     Period to Voltage     Sine to Square Wave      Voltage Converters     Voltage to Frequency      DC to DC Power Supplies   High Voltage Power Supplies   
Switchmode Power Supplies       Voltage Controlled Oscillators

• Line Powered 60Hz Clock Generator
  This circuit is connected to the 120vac power line and transfers 60Hz clock pulses to a logic circuit. The optoisolator used provides 5000 volts of isolation between the power line and the logic side of the circuit
   
• Wide Band Zero Cross Detector
  This circuit was designed to convert a low amplitude 40KHz signal into a clean square wave signal.  It will work with inputs as small as 5mv peak-to-peak or as large as 3 volts peak to peak.  The input frequency can range from a few kilohertz to about 150KHz.