Patent ID: 9595950
Date: 2017-03-14
CPC Classifications: H03K

Claim:
1. An apparatus comprising: a first field effect transistor (FET) having a gate, a source and a drain; a second FET having a gate, a source and a drain, wherein the source of the second FET is coupled to the drain of the first FET; a third FET having a gate, a source and a drain, wherein the source of the third FET is coupled to the drain of the second FET; a first bipolar transistor having a base, an emitter, and a collector, wherein the collector of the first bipolar transistor is coupled to the source of the second FET; a second bipolar transistor having a base, an emitter, and a collector, wherein the collector of the second bipolar transistor is coupled to the source of the third FET; a first diode having an anode an a cathode, wherein the cathode of the first diode is coupled to the emitter of the first bipolar transistor; a second diode having an anode an a cathode, wherein the anode of the second diode is coupled to the anode of the first diode, and wherein the cathode of the second diode is coupled to the emitter of the second bipolar transistor; a first resistor coupled between the anode of the first diode and the gate of the first FET; a second resistor; a third diode, wherein the second resistor and the third diode are coupled in series between the base of the first bipolar transistor and the source of the first FET; a third resistor; and a fourth diode, wherein the third resistor and the fourth diode are coupled in series between the base of the second bipolar transistor and the source of the second FET.