Chopper Control Circuit
Original Publication Date: 1989-Oct-01
Included in the Prior Art Database: 2005-Jan-29
Chopping coil drivers eliminate high-wattage limiting resistors and improve electromechanical performance by allowing the coil current to reach the desired level faster. Coil current is limited to a specific value by chopping (switching) the power supply on and off across the coil. The chopping rate can be determined either by the natural time constant (L/R) of the circuit and load or by an external oscillator. Forced frequency chopping, through the use of an external oscillator, eliminates audible noise pollution and provides a tighter toleranced maximum average current and a smaller delta chopping current.