Power receiving apparatus and control circuit thereof

Patent metadata

Field	Value
Publication number	US-10622802-B2
Application number	US-201715648890-A
Country	US
Kind code	B2
Filing date	Jul 13, 2017
Priority date	Jul 13, 2016
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

A power receiving apparatus receives a bus voltage from a power supply apparatus via a cable, and supplies the bus voltage to a load circuit. A power receiver side controller receives, as a power supply, a voltage VADP of a bus line that is more toward a bus switch. The power receiver side controller is capable of communicating with a power supply side controller of the power supply apparatus. Furthermore, the power receiver side controller determines the voltage to be supplied based on a negotiation, and controls the bus switch. A short circuit detection circuit detects a short circuit of a bus line that is more toward the load circuit side than the bus switch.

First claim

What is claimed is:

1. A power receiving apparatus structured to receive a bus voltage from a power supply apparatus via a cable, and to supply the bus voltage to a load circuit, the power receiving apparatus comprising:
a bus line structured to extend from a receptacle, into which the cable is to be inserted, to the load circuit;
a bus switch arranged on a path of the bus line;
a power receiver side controller structured to receive, as a power supply, a voltage on the bus line that is more toward the receptacle than the bus switch, to communicate with a power supply side controller of the power supply apparatus, to determine a voltage to be supplied based on a negotiation, and to control the bus switch; and
a short circuit detection circuit structured to detect a short circuit of the bus line that is more toward the load circuit than the bus switch during an off state of the bus switch.

2. The power receiving apparatus according to claim 1 , wherein the short circuit detection circuit is structured to be switchable between an on state and an off state,
wherein the short circuit detection circuit comprises a charger circuit structured to charge the bus line that is more toward the load circuit than the bus to an internal voltage in the on state,
and wherein the short circuit detection circuit is structured to detect a short circuit based on the internal voltage.

3. The power receiving apparatus according to claim 2 , wherein the charger circuit comprises a charging switch arranged on a sub-path arranged in parallel with the bus switch,
and wherein the charger circuit has an impedance that is higher than that of the bus switch.

4. The power receiving apparatus according to claim 3 , wherein the charger circuit further comprises a charging resistor arranged on the sub-path such that it is coupled in series with the charging switch.

5. The power receiving apparatus according to claim 2 , wherein the charger circuit comprises a current source.

6. The power receiving apparatus according to claim 1 , wherein the short circuit detection circuit comprises a comparator structured to compare the internal voltage with a predetermined threshold voltage.

7. The power receiving apparatus according to claim 1 , structured to be compatible with the USB-PD specification.

8. The power receiving apparatus according to claim 1 , structured to be compatible with the USB Type-C specification,
wherein the power receiver side controller is structured to set a pull-down resistor coupled to a CC (Configuration Channel) port to an open state when the short circuit detection circuit detects a short circuit.

9. The power receiving apparatus according to claim 1 , wherein, when the short circuit detection circuit detects a short circuit, the power receiver side controller fixes the bus switch to the off state.

10. An electronic device comprising the power receiving apparatus according to claim 1 .

11. A control circuit structured to be employed in a power receiving apparatus structured to receive a bus voltage from a power supply apparatus via a cable, and to supply the bus voltage to a load circuit, wherein, in addition to the control circuit, the power receiving apparatus comprises:
a bus line structured to extend from a receptacle, into which the cable is to be inserted, to the load circuit; and
a bus switch arranged on a path of the bus line,
and wherein the control circuit comprises:
a communication circuit structured to communicate with a power supply side controller of the power supply apparatus;
a logic circuit structured to determine a voltage to be supplied, based on a negotiation with the power supply side controller, and to control the bus switch; and
a short circuit detection circuit structured to detect a short circuit of the bus line that is more toward the load circuit than the bus switch in a state in which the logic circuit has the bus switch turned off.

12. The control circuit according to claim 11 , wherein the power receiving apparatus further comprises a charger circuit structured to be switchable between an on state and an off state, and to charge the bus line that is more toward the load circuit side than the bus switch in the on state,
and wherein the short circuit detection circuit is structured to detect a short circuit of the bus line based on a voltage on the bus line in the on state of the charger circuit.

13. The control circuit according to claim 12 , wherein the charger circuit comprises a charging switch arranged on a sub-path arranged in parallel with the bus switch,
and wherein the charger circuit is structured to have an impedance that is higher than that of the bus switch.

14. The control circuit according to claim 13 , wherein the charger circuit further comprises a charging resistor arranged on the sub-path such that it is coupled in series with the charging switch.

15. The control circuit according to claim 12 , wherein the charger circuit comprises a current source.

16. The control circuit according to claim 11 , wherein the short circuit detection circuit comprises a comparator structured to compare the voltage on the bus line with a predetermined threshold voltage.

17. The control circuit according to claim 11 , structured to be compatible with the USB-PD specification.

18. The control circuit according to claim 11 , structured to compatible with the USB Type-C specification,
wherein the control circuit is structured to set a pull-down resistor coupled to a CC (Configuration Channel) port to an open state when the short circuit detection circuit detects a short circuit.

19. The control circuit according to claim 11 , wherein, when the short circuit detection circuit detects a short circuit, the control circuit fixes the bus switch to the off state.

20. An operating method for a power supply system that is compatible with the USB-PD specification, wherein the power supply system comprises a power supply apparatus and a power receiving apparatus,
wherein the power receiving apparatus comprises:
a bus line structured to extend from a receptacle, into which a cable is to be inserted, to a load circuit; and
a bus switch arranged on a path of the bus line,

and wherein the operating method comprises:
determining a bus voltage based on a negotiation between the power supply apparatus and the power receiving apparatus;
supplying, by means of the power supply apparatus, the bus voltage thus determined based on the negotiation to the power receiving apparatus;
transmitting, by means of the power supply apparatus, a notice of the supplying of the bus voltage;
detecting, by means of the power receiving apparatus, a short circuit on a side that is more toward the load circuit than the bus switch in response to the notice before the bus switch is turned on; and
turning on the bus switch under a condition of non-detection of a short circuit.

Assignees

• Rohm Co Ltd

Inventors

• KOGA Fuminori
• Motoki Kenichi

Classifications

• H02H11/005

  in case of too low isolation resistance, too high load, short-circuit; earth fault · CPC title

• H02H1/0007

  concerning the detecting means (in general G01R or other subclasses of G01; reed switches H01H71/2445) · CPC title

• H02J7/00

  Circuit arrangements for charging or discharging batteries or for supplying loads from batteries · CPC title

• H02H7/26

  Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured (locating faults in cables G01R31/08) · CPC title

• H02J2007/0062

  Electricity · mapped topic