This is the Scarce Level Power Fet Driver Method Circuit Diagram. This circuit operates from a 16- to 50-V supply. Adding the buffer circuit (within the dashed lines) offers 100-ns switching times. Otherwise, the circuit switches in 1 /xs. Ql and R1 form a switched current source of about 12 mA.
The current flows through R2, which supplies 12 V to the FET. The circuit works well over a wide range of supply voltages. Furthermore, it switches smoothly in the presence of large ripple and noise on the supply.
Scarce Level Power Fet Driver Method Circuit Diagram
The switching time (about 1 /as) can be reduced considerably by lowering the values of Ri and R2 at the expense of higher power dissipation in the resistors and Ql. Alternatively, a buffer circuit can be added to produce switching times of 100 ns without generating significant power dissipation.