CONTROL DEVICE AND POWER SUPPLY DEVICE
A control device includes: a control circuit that controls a power supply circuit by a feedback of an output from an output terminal, the power supply circuit having a first transistor, the first transistor including gallium nitride material and having a source and a drain connected so that one of the source and the drain is connected to a first power supply and an other of the source and the drain is connected to the output terminal; and a first terminal via which a first control signal output by the control circuit is output to a gate of the first transistor.
1 . A control device comprising:
a control circuit that controls a power supply circuit by a feedback of an output from an output terminal, the power supply circuit having a first transistor, the first transistor including gallium nitride material and having a source and a drain connected so that one of the source and the drain is connected to a first power supply and an other of the source and the drain is connected to the output terminal; and
a first terminal via which a first control signal output by the control circuit is output to a gate of the first transistor.
2 . The control device according to claim 1 , further comprising:
a second terminal connected to the output terminal; and
a first protection circuit that prevents surge current applied to the second terminal to the first power supply and causes the surge current to flow to a second power supply having a voltage lower than that of the first power supply.
3 . The control device according to claim 2 , further comprising a switch connected between the first terminal and the second power supply.
4 . The control device according to claim 1 , further comprising a switch connected between the first terminal and a second power supply having a voltage lower than that of the first power supply.
5 . The control device according to claim 1 , further comprising one of an n-type diffusion resistor and a polysilicon resistor connected to the second terminal.
6 . The control device according to claim 1 , wherein:
the power supply circuit includes a second transistor connected so that one of a source and a drain of the second transistor is connected to the other of the source and the drain of the first transistor, and an other of the source and the drain of the second transistor is connected to a second power supply having a voltage lower than that of the first voltage; and
the control device has a third terminal via which a second control signal output by the control circuit is output to a gate of the second transistor.
7 . The control device according to claim 1 , further comprising a second transistor connected so that one of a source and a drain of the second transistor is connected to the other of the source and the drain of the first transistor, and an other of the source and the drain of the second transistor is connected to a second power supply having a voltage lower than that of the first voltage,
wherein the control circuit outputs a second control signal to a gate of the second transistor.
8 . The control device according to claim 6 , wherein the power supply circuit includes an inductor having one end connected to the other of the source and the drain of the first transistor and an other end connected to the output terminal, and a capacitor having one end connected to the output terminal and an other end connected to the second power supply.
9 . The control device according to claim 7 , wherein the power supply circuit includes an inductor having one end connected to the other of the source and the drain of the first transistor and an other end connected to the output terminal, and a capacitor having one end connected to the output terminal and an other end connected to the second power supply.
10 . The control device according to claim 3 , further comprising a third terminal to which a third control signal that turns on or off the switch is input.
11 . The control device according to claim 4 , further comprising a third terminal to which a third control signal that turns on or off the switch is input.
12 . The control device according to claim 10 , further comprising a second protection circuit that causes a surge current applied to the fourth terminal to the second power supply.
13 . The control device according to claim 11 , further comprising a second protection circuit that causes a surge current applied to the fourth terminal to the second power supply.
14 . The control device according to claim 3 , wherein the switch turned on when a voltage of a sixth terminal connected to the first power supply is equal to or smaller than a reference value.
15 . The control device according to claim 4 , wherein the switch is turned on when a voltage of a sixth terminal connected to the first power supply is equal to or smaller than a reference value.
16 . The control device according to claim 7 , further comprising:
a fifth terminal connected to the other of the source and the drain of the first transistor; and
a third protection circuit that prevents a surge current applied to the fifth terminal from flowing to the first power supply and causes the surge current to flow to the second power supply.
17 . A power supply device comprising:
a control device; and
a first transistor including GaN having a source and a drain,
the control device including a control circuit that controls a power supply circuit by a feedback of an output from an output terminal, the power supply circuit having the first transistor connected so that one of the source and the drain is connected to a first power supply and an other of the source and the drain is connected to the output terminal; and
a first terminal via which a first control signal output by the control circuit is output to a gate of the first transistor.