Control device, power receiving device, electronic apparatus, and power transmission system

A control device included in a power transmitting device that contactlessly transmits power to a power receiving device, the control device comprising:

• a control portion that controls a power transmission portion in the power transmitting device that transmits power to the power receiving device,
• wherein the control portion, after causing the power transmission portion to transmit a signal having a first frequency and a first duty to the power receiving device,
• in a case of issuing a first command to the power receiving device, causes the power transmission portion to transmit a signal having a second frequency that is different from the first frequency, or a signal having a second duty that is different from the first duty, during a period having a first length, and
• in a case of issuing a second command that is different from the first command to the power receiving device, causes the power transmission portion to transmit the signal having the second frequency or the signal having the second duty, during a period having a second length that is different from the first length.

A control device included in a power transmitting device that contactlessly transmits power to the power receiving device, the control device comprising:

• a control portion that controls a power transmission portion in the power transmitting device that transmits power to the power receiving device,
• wherein the control portion, after causing the power transmission portion to be driven at a first frequency and a first duty,
• in a case of issuing a first command to the power receiving device, causes the power transmission portion to be driven at a second frequency that is different from the first frequency or at a second duty that is different from the first duty, during a period having a first length, and
• in a case of issuing a second command that is different from the first command to the power receiving device, causes the power transmission portion to be driven at the second frequency or at the second duty, during a period having a second length that is different from the first length.

A power transmission system including a power transmitting device and a power receiving device,

• wherein the power transmitting device transmits a signal having a first frequency and a first duty to the power receiving device, and
• in a case where the power receiving device is notified of an issued command, transmits a signal having a second frequency that is different from the first frequency or a signal having a second duty that is different from the first duty during a period having a length corresponding to the issued command, and
• the power receiving device, after receiving the signal having the first frequency and the first duty from the power transmitting device,
• receives the signal having the second frequency or the signal having the second duty from the power transmitting device, and
• specifies the issued command based on a length of a reception period of the signal having the second frequency or the signal having the second duty.