Overvoltage protection of transistor devices

An overvoltage protection circuit for a transistor device, the overvoltage protection circuit comprising:

• a first pin coupled to a gate terminal of the transistor device;
• an electrostatic discharge protection circuit coupled between a second pin and a source terminal of the transistor device;
• a first diode coupled between the first pin and the second pin;
• and
• a second diode coupled in parallel to the first diode between the first pin and the second pin, wherein the forward direction of the first diode is opposite to the forward direction of the second diode,
• wherein the electrostatic discharge protection circuit is a first electrostatic discharge protection circuit;
• and
• the overvoltage protection circuit further comprises:
• a third pin for bonding to the first pin;
• a second electrostatic discharge protection circuit coupled between the third pin and a fourth pin and the source terminal of the transistor device;
• and
• the fourth pin for coupling to an external line.

A method of measuring a gate leakage current of a transistor device coupled to an overvoltage protection circuit for a transistor device, the overvoltage protection circuit comprising:

• a first pin coupled to a gate terminal of the transistor device;
• an electrostatic discharge protection circuit coupled between a second pin and a source terminal of the transistor device;
• a first diode coupled between the first pin and the second pin;
• and
• a second diode coupled in parallel to the first diode between the first pin and the second pin, wherein the forward direction of the first diode is opposite to the forward direction of the second diode,
• the method comprising the steps of:
• adjusting a voltage at the second pin to be substantially equal to a voltage at the first pin;
• measuring a current flowing into the gate of the transistor device;
• and
• varying the voltage at the first pin and adjusting the voltage at the second pin to follow the voltage at the first pin.

A method of measuring a gate leakage current of a transistor device, the method comprising:

• providing a first pin coupled to a gate terminal of the transistor device;
• providing an electrostatic discharge protection circuit coupled between a second pin and a source terminal of the transistor device;
• providing a first diode coupled between the first pin and the second pin;
• providing a second diode coupled in parallel to the first diode between the first pin and the second pin, wherein the forward direction of the first diode is opposite to the forward direction of the second diode;
• adjusting a voltage at the second pin to be substantially equal to a voltage at the first pin;
• measuring a current flowing into the gate of the transistor device;
• and
• varying the voltage at the first pin and adjusting the voltage at the second pin to follow the voltage at the first pin.