Resonant Drive Circuit for Power Field-Effect Transistors
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
A drive circuit consisting of a switching stage (Q3), a drive transformer (T1) and a clamp circuit (CR1-CR2) is used to drive a field-effect transistor (FET). The circuit configuration is such that when the switching stage is on, the power FET is off, and vice versa. Fig. 1 shows the basic circuit configuration. The circuit is comprised of a switching transistor (Q3) coupled through its collector to the primary winding of a transformer (T1). The primary winding, in turn, is coupled through a resistor (R1) to a voltage supply (+V2). The secondary winding of the transformer is connected to the gate (G) and source (S) of the power FET (Q1). A clamping circuit (CR1 and CR2) is connected in parallel to the gate and source terminals of Q1. Fig.