DCDC converter, semiconductor device, and power generation device

Patent metadata

Field	Value
Publication number	US-9362820-B2
Application number	US-201113239515-A
Country	US
Kind code	B2
Filing date	Sep 22, 2011
Priority date	Oct 7, 2010
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

A DCDC converter includes a control circuit, a transistor in which switching is controlled by being supplied voltage output from the control circuit to a gate electrode of the transistor, a voltage conversion portion in which supply of input voltage is controlled by the switching of the transistor and output power commensurate with duty ratio of the switching of the transistor, and a detection circuit detecting the output power. Further, the control circuit includes a control signal generation circuit generating a control signal with a pulse voltage waveform and a selection circuit applying voltage of the control signal to the gate electrode in the case where current detected by the detection circuit is the same as or exceeds the threshold value and applying voltage for turning on the transistor to the gate electrode in the case where the current detected by the detection circuit falls below the threshold value.

First claim

What is claimed is:

1. A DCDC converter comprising:
a control circuit;
a transistor in which switching is controlled by supply of voltage output from the control circuit to a gate of the transistor;
a voltage conversion portion in which supply of input voltage is controlled by the switching of the transistor and output power commensurate with a duty ratio of the switching of the transistor is generated; and
a detection circuit configured to detect the output power,
wherein the control circuit comprises:
a control signal generation circuit configured to generate a control signal with a pulse voltage waveform; and
a selection circuit configured to apply voltage of the control signal to the gate of the transistor in the case where the output power detected by the detection circuit is the same as or exceeds a threshold value and apply the input voltage to the gate of the transistor in the case where the output power detected by the detection circuit falls below the threshold value.

2. A semiconductor device, wherein the DCDC converter described in claim 1 is used.

3. A power generation device comprising:
the DCDC converter described in claim 1 ;
a power generation portion configured to supply generated power to the DCDC converter as input voltage; and
a power storage portion in which charging is performed utilizing output voltage from the DCDC converter.

4. The power generation device according to claim 3 , wherein a photo diode is used for the power generation portion.

5. A DCDC converter according to claim 1 , wherein the output power detected by the detection circuit is voltage of the output power.

6. A DCDC converter according to claim 1 , wherein the output power detected by the detection circuit is a current of the output power.

7. A DCDC converter comprising:
a control circuit;
a transistor in which switching is controlled by supply of voltage output from the control circuit to a gate of the transistor;
a voltage conversion portion in which supply of input voltage is controlled by the switching of the transistor and output power commensurate with a duty ratio of the switching of the transistor is generated; and
a detection circuit,
wherein the control circuit comprises a control signal generation circuit and a selection circuit,
wherein the control signal generation circuit comprises:
a plurality of resistors configured to generate a feedback signal by dividing a voltage of the output power;
a differential amplifier in which voltage of the feedback signal is applied to an inverting input terminal and a reference voltage is applied to a non-inverting input terminal;
a triangle wave generator configured to generate a triangle wave or a sawtooth wave; and
a comparator configured to generate a control signal with a pulse voltage waveform by application of voltage output from the differential amplifier to the non-inverting input terminal and by application of an output signal output from the triangle wave generator to the inverting input terminal,

wherein the detection circuit is configured to detects voltage output from the differential amplifier, and
wherein the detection circuit comprises the selection circuit configured to apply voltage of the control circuit to the gate of the transistor in the case where voltage output from the differential amplifier detected by the detection circuit is the same as or exceeds a threshold value and apply the input voltage to the gate of the transistor in the case where voltage output from the differential amplifier detected by the detection circuit falls below the threshold value.

8. A semiconductor device, wherein the DCDC converter described in claim 7 is used.

9. A power generation device comprising:
the DCDC converter described in claim 7 ;
a power generation portion configured to supply generated power to the DCDC converter as input voltage; and
a power storage portion in which charging is performed utilizing output voltage from the DCDC converter.

10. The power generation device according to claim 9 , wherein a photo diode is used for the power generation portion.

Assignees

• Ito Yoshiaki
• Takahashi Kei
• Semiconductor Energy Lab

Inventors

• Ito Yoshiaki
• Takahashi Kei

Classifications

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title

• Y02B70/10

  Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes · CPC title

• H02M1/0032

  Control circuits allowing low power mode operation, e.g. in standby mode · CPC title

• H02M1/0009

  Devices or circuits for detecting current in a converter · CPC title

• H02M1/08

  Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters · CPC title