Transistor control circuit and power supply device
A transistor control circuit includes: an electrode control circuit configured to apply a positive potential to a control electrode in a transistor that includes the control electrode between a gate and a drain.
1. A transistor control circuit comprising:
a transistor includes a gate electrode with a gate field plate, a drain electrode and a control electrode formed on top of an inter-layer insulating film between the gate field plate and the drain electrode;
a comparator circuit compares a drain voltage of the transistor with reference voltages; and
an electrode control circuit generates a voltage to impart to the control electrode on the basis of the comparison results from the comparator circuit.
2. The transistor control circuit according to claim 1 , wherein
the electrode control circuit applies a first positive potential, and a second positive potential that is higher than the first potential, to the control electrode.
3. The transistor control circuit according to claim 1 , wherein the drain voltage determination circuit includes
a voltage division circuit configured to divide the drain voltage,
a comparison voltage generation circuit configured to generate a plurality of comparison voltages, and
a comparison circuit configured to compare a drain voltage divided by the voltage division circuit against the plurality of comparison voltages.
4. The transistor control circuit according to claim 1 , wherein
the transistor is realized by a compound semiconductor that includes nitrogen.
5. A power supply device comprising:
a DC-DC converter; and
a power supply circuit configured to supply power to the DC-DC converter, the power supply circuit including
a transistor includes a gate electrode with a gate field plate, a drain electrode and a control electrode formed on top of an inter-layer insulating film between the gate field plate and the drain electrode,
a comparator circuit compares a drain voltage of the transistor with reference voltages, and
an electrode control circuit generates a voltage to impart to the control electrode on the basis of the comparison results from the comparator circuit.