Electronic device, communication system, and method of controlling electronic device

Patent metadata

Field	Value
Publication number	US-2016190863-A1
Application number	US-201414896474-A
Country	US
Kind code	A1
Filing date	Sep 3, 2014
Priority date	Sep 20, 2013
Publication date	Jun 30, 2016
Grant date	—

Abstract

There are provided an electronic device, a communication system, and a method of controlling an electronic device which are capable of reducing the number of times manipulation associated with communication using a solar cell. The electronic device includes a solar cell, a secondary battery that is charged by the solar cell, and a control circuit that switches between a charging period during which the charging of the secondary battery from the solar cell is performed and a communication period during which an optical signal is received by the solar cell.

First claim

1 . An electronic device comprising:
a solar cell; a secondary battery that is charged by the solar cell; and a control circuit that switches between a charging period during which the charging of the secondary battery from the solar cell is performed and a communication period during which an optical signal is received by the solar cell.

2 . The electronic device according to claim 1 , further comprising:
a switch that switches a connected state of the solar cell and the secondary battery, wherein the control circuit controls the switch such that the secondary battery is disconnected from the solar cell during the communication period, and controls the switch such that the secondary battery is connected to the solar cell during the charging period.

3 . The electronic device according to claim 2 ,
wherein the control circuit detects a voltage value of the secondary battery, determines whether or not the detected voltage value is greater than a first threshold, and controls the switch such that the secondary battery is disconnected from the solar cell when it is determined that the detected voltage value is greater than the first threshold.

4 . The electronic device according to claim 2 ,
wherein the control circuit detects the voltage value of the secondary battery, determines whether or not the detected voltage value is less than a second threshold, and controls the switch such that the secondary battery is connected to the solar cell when it is determined that the detected voltage value is less than the second threshold.

5 . The electronic device according to claim 1 ,
wherein the optical signal includes a synchronization signal indicating the transmission of data, and the data, and a period of the synchronization signal is longer than the charging period.

6 . The electronic device according to claim 5 ,
wherein the control circuit switches between the communication period and the charging period after the data is received during the communication period.

7 . The electronic device according to claim 5 ,
wherein, when the data is not received during the communication period, the control circuit switches from the communication period to the charging period after a predetermined amount of time elapses.

8 . The electronic device according to claim 5 , further comprising:
a switch that switches a connected state of the solar cell and the secondary battery, wherein the control circuit controls the switch such that the secondary battery is disconnected from the solar cell during the communication period, and controls the switch such that the secondary battery is connected to the solar cell during the charging period.

9 . The electronic device according to claim 8 ,
wherein the control circuit detects a voltage value of the secondary battery, determines whether or not the detected voltage value is greater than a first threshold, and controls the switch such that the secondary battery is disconnected from the solar cell when it is determined that the detected voltage value is greater than the first threshold.

10 . The electronic device according to claim 8 ,
wherein the control circuit detects the voltage value of the secondary battery, determines whether or not the detected voltage value is less than a second threshold, and controls the switch such that the secondary battery is connected to the solar cell when it is determined that the detected voltage value is less than the second threshold.

11 . The electronic device according to claim 5 , further comprising:
a generation circuit that generates a reference signal for generating time information, wherein, when time information regarding time is included in the data, the control circuit resets the reference signal based on the received time information.

12 . The electronic device according to claim 11 ,
wherein a period of the optical signal is a cycle of the reference signal.

13 . The electronic device according to claim 11 ,
wherein the control circuit switches between the communication period and the charging period at a predetermined time based on the received time information after the reference signal is reset.

14 . The electronic device according to claim 1 ,
wherein the control circuit measures a voltage value of the solar cell at predetermined time intervals, and switches from the charging period to the communication period when a pattern constructed by a plurality of states of the measured voltage values is coincident with a predetermined pattern.

15 . The electronic device according to claim 1 ,
wherein, during the communication period, the control circuit receives a synchronization signal which is included in the optical signal and indicates the transmission of the optical signal at a first communication rate, and then receives data included in the optical signal by switching to a second communication rate greater than the first communication rate.

16 . The electronic device according to claim 15 ,
wherein the control circuit controls such that the optical signal is received at the first communication rate when the period is switched from the charging period to the communication period.

17 . The electronic device according to claim 15 ,
wherein the control circuit switches from the second communication rate to the first communication rate after the data is received.

18 . The electronic device according to claim 15 ,
wherein the control circuit switches from the second communication rate to the first communication rate when the period is switched from the communication period to the charging period.

19 . The electronic device according to claim 15 ,
wherein, when the data is not received during the communication period, the control circuit switches from the second communication rate to the first communication rate after a predetermined amount of time elapses.

20 . The electronic device according to claim 15 ,
wherein the synchronization signal, a start signal indicating the transmission start of the data and the data of the optical signal are transmitted in sequence, and the control circuit switches from the first communication rate to the second communication rate when it is determined that the synchronization signal is received.

21 . The electronic device according to claim 20 ,
wherein, when information that is included in the synchronization signal and indicates the end of the synchronization signal is received, the control circuit switches from the first communication rate to the second communication rate, and receives the start signal and the data.

22 . The electronic device according to claim 20 ,
wherein, when the start signal is received, the control circuit switches from the first communication rate to the second communication rate.

23 . The electronic device according to claim 15 ,
wherein the synchronization signal is a signal of which a first half is a first signal pattern and a second half is a second signal pattern, and the control circuit controls such that the first communication rate is maintained when the synchronization signal having the first signal pattern is received, and controls such that the communication rate is switched from the first communication rate to the second communication rate when the synchronization signal having the second signal pattern is received.

24 . The electronic device according to claim 15 ,
wherein at least one timing of timings when the fir

Assignees

• Seiko Instr Inc

Inventors

• Ogasawara Kenji
• Takakura Akira
• Maesawa Tamotsu
• Koyama Kazuhiro

Classifications

• H02J7/61

  against overcharge · CPC title

• H02J7/963

  in response to battery voltage gradient · CPC title

• H02J7/663

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• H02J2207/10

  Control circuit supply, e.g. means for supplying power to the control circuit · CPC title

• H02J7/35 Primary

  with light sensitive cells · CPC title