DC-DC converter

Patent metadata

Field	Value
Publication number	US-10008935-B2
Application number	US-201715497725-A
Country	US
Kind code	B2
Filing date	Apr 26, 2017
Priority date	Apr 28, 2016
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

There is provided a DC-DC converter which is safe and secure, but yet with low power consumption. The DC-DC converter is configured to monitor the output voltage of an error amplifier, and detect that the output voltage of the error amplifier becomes a fixed value or smaller to drive an overheat protection circuit and a supply voltage monitoring circuit intermittently.

First claim

What is claimed is:

1. A DC-DC converter, comprising:
a switching element connected between a first end of an inductor, and an input terminal of the DC-DC converter, the inductor having second end at which an output voltage is generated;
an error amplifier that monitors the output voltage;
an output control circuit that outputs a control signal to a gate of the switching element based on an output signal of the error amplifier; and
a protection circuit that outputs a signal to the output control circuit to turn off the switching element when detecting an abnormal state,
wherein the protection circuit operates intermittently only for a predetermined period of time in response to a signal based on the output signal of the error amplifier.

2. The DC-DC converter according to claim 1 , wherein the predetermined period is a period during which at least the switching element is on.

3. The DC-DC converter according to claim 1 , wherein the protection circuit comprises a supply voltage monitoring circuit that detects an abnormal state when the supply voltage is a predetermined voltage or lower.

4. The DC-DC converter according to claim 1 , wherein the protection circuit comprises an overheat protection circuit that detects an abnormal state when an ambient temperature is a predetermined temperature or higher.

5. A DC-DC converter comprising:
a switching element connected between a first end of an inductor, and an input terminal of the DC-DC converter, the inductor having a second end at which an output voltage is generated;
an error amplifier that monitors the output voltage;
an output control circuit that outputs a control signal to a gate of the switching element based on an output signal of the error amplifier;
a protection circuit that outputs a signal to the output control circuit to turn off the switching element when detecting an abnormal state,
wherein the protection circuit operates intermittently only for a predetermined period of time in response to a signal based on the output signal of the error amplifier; and
a comparator that outputs a control signal to cause the protection circuit to operate intermittently based on the output signal of the error amplifier.

Assignees

• Sii Semiconductor Corp
• Ablic Inc

Inventors

• Kawano Akihiro
• Goto Katsuya

Classifications

• G01K3/005

  Circuits arrangements for indicating a predetermined temperature (fire detection G08B17/00) · CPC title

• H02M3/158 Primary

  including plural semiconductor devices as final control devices for a single load · CPC title

• H02M2001/327

  Electricity · mapped topic

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title

• G01R19/16576

  comparing DC or AC voltage with one threshold (G01R19/16514, G01R19/16519, G01R19/16528, G01R19/16533 and G01R19/1659 take precedence) · CPC title