JP2010172088A - Electronic apparatus and charging control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently use power generated at, for example, a solar panel. <P>SOLUTION: A portable telephone 1 comprises a switch 45 arranged in a current feed passage from a solar charging circuit 30 to a secondary battery 50, and a CPU 70 can feed a current to the secondary battery 50 from the solar charging circuit 30. The switch 45 is turned off when a current value I of the consumption current of a circuit block B is smaller than a current threshold Ith, and the switch 45 is turned on when the current value I is larger than or equal to the current threshold Ith so long as a temperature T of the secondary battery 50 is higher than or equal to a temperature threshold Tth decided on the basis of the charging operation assurance range of the secondary battery 50. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to charge control of a secondary battery.

2. Description of the Related Art In recent years, a mobile phone including a solar panel and having a function of charging a secondary battery by supplying electric power obtained by power generation of the solar panel to the secondary battery has been proposed (see, for example, Patent Document 1). .)
By the way, since the secondary battery should be charged at a temperature within the charging operation guarantee range, the charging of the secondary battery is usually suspended when the temperature of the secondary battery exceeds the upper limit of the charging operation guarantee range. It is supposed to be.

JP 2007-97330 A

  However, although the power generated by the solar panel is high under severe sunlight conditions, the secondary battery temperature exceeds the guaranteed charging operation range in this environment, and charging of the secondary battery is interrupted. The power generated in the solar panel is no longer used. It should be noted that efficient use of the power generated by the power generation mechanism is desired regardless of whether it is a power generation mechanism other than a solar panel or an electronic device other than a mobile phone.

  Accordingly, the present invention provides an electronic device and a charge control method capable of effectively using, for example, power generated in a solar panel and effectively suppressing a decrease in the remaining battery level of a secondary battery. With the goal.

  In order to achieve the above object, an electronic device according to the present invention is an electronic device including a secondary battery and a charging unit that charges the secondary battery, and is provided in a current supply path from the charging unit to the secondary battery. A circuit block including a switch means and a control means provided, and receiving a current supply from the secondary battery and receiving a current supply from the charging means via the switch means; and detecting a temperature of the secondary battery Temperature detecting means, and current detecting means for detecting a current value of current consumption by the circuit block, wherein the control means can supply current from the charging means to the secondary battery, and the temperature detecting means If the current value detected by the current detection means is less than the predetermined current value, the switch means is turned off and the predetermined temperature is detected. To turn on the switch means when the above current values.

  The charge control method of the present invention includes a secondary battery, a charging means for charging the secondary battery, a switch means provided in a current supply path from the charging means to the secondary battery, and a control means. Including a circuit block that receives current supply from the secondary battery and receives current supply from the charging unit via the switch unit, and a charge control method performed in an electronic device having the control unit, When the current can be supplied from the charging means to the secondary battery and the temperature of the secondary battery is equal to or higher than a predetermined temperature, and the current value of the current consumed in the circuit block is less than the predetermined current value The switch means is turned off, and the switch means is turned on when the predetermined current value is exceeded.

  The electronic device of the present invention is an electronic device comprising a secondary battery and a charging means for charging the secondary battery, the switch means provided in the current supply path from the charging means to the secondary battery, A circuit block that includes a control unit and receives a current supply from the secondary battery and receives a current supply from the charging unit via the switch unit; and a temperature detection unit that detects a temperature of the secondary battery. The control means is capable of supplying current from the charging means to the secondary battery, and the circuit block is less than a predetermined current value when the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature. The switch means is turned off when an operation that consumes a predetermined current is performed, and the switch means is turned on when an operation that consumes a current greater than the predetermined current value is performed. That.

  The charge control method of the present invention includes a secondary battery, a charging means for charging the secondary battery, a switch means provided in a current supply path from the charging means to the secondary battery, and a control means. Including a circuit block that receives current supply from the secondary battery and receives current supply from the charging unit via the switch unit, and a charge control method performed in an electronic device having the control unit, When the charging means can supply current to the secondary battery, and the temperature of the secondary battery is equal to or higher than a predetermined temperature, the circuit block performs an operation of consuming a current less than a predetermined current value. The switch means is sometimes turned off, and the switch means is turned on when an operation that consumes a current greater than the predetermined current value is performed.

  According to each of the electronic device and the charge control method, the secondary battery can be effectively controlled.

1 is an external view of a mobile phone according to a first embodiment. The circuit diagram of the mobile telephone of FIG. FIG. 3 is a circuit diagram of the LDO of FIG. 2. FIG. 3 is a diagram illustrating conditions for driving and stopping the LDO of FIG. 2 and switching on and off. The flowchart which shows the procedure of the control processing of LDO and switch by CPU of FIG. 3 is a timing chart for explaining an operation example of the mobile phone in FIG. 2. The timing chart for demonstrating the other operation example of the mobile telephone of FIG. The timing chart for demonstrating the further another operation example of the mobile telephone of FIG. The circuit diagram of the mobile phone of a 2nd embodiment. FIG. 10 is a diagram illustrating conditions for driving and stopping the LDO of FIG. 9 and switching on and off. 10 is a flowchart showing a procedure of LDO and switch control processing by the CPU of FIG. 9;

<< First Embodiment >>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
<Appearance of mobile phone>
The appearance of the mobile phone according to the present embodiment will be described with reference to FIG. FIG. 1A is a front view of the cellular phone according to the present embodiment in an open state, and FIG. 1B is a rear view thereof.

  The mobile phone 1 includes housings 2 and 3, which are configured to be able to be opened and closed by being connected to each other via a hinge portion 4 so as to be foldable. In addition, a display unit 5 and a speaker unit 6 configured by a liquid crystal display or the like are disposed on the facing surface 2a of the housing 2 that faces the housing 3 when folded. A key operation unit 7 and a microphone 8 are arranged on the facing surface 3a of the housing 3 that faces the housing 2 when folded. Further, an antenna 9 is disposed in the vicinity of the hinge portion 4 of the housing 3. Furthermore, as shown in FIG.1 (b), the solar panel (solar cell) 10 for performing a photovoltaic power generation is arrange | positioned on the surface opposite to the opposing surface 2a of the housing 2. As shown in FIG.

<Configuration of mobile phone>
A functional configuration of the mobile phone 1 of FIG. 1 will be described with reference to FIG. FIG. 2 is a circuit diagram of the mobile phone 1 of FIG.
The cellular phone 1 includes a solar panel 10 for performing the above-described photovoltaic power generation, a solar charging circuit 30, a capacitor (capacitance element) 40, a switch 45, a secondary battery 50, a current detection circuit 55, and a circuit block. B and an AC adapter 90 are provided. The circuit block B includes a quick charging circuit 60, a CPU (Central Processing Unit) 70, and a memory 80.

The solar panel 10 has a maximum output voltage of, for example, 6.0 V to 6.2 V. The maximum output voltage is not limited to this.
The solar charging circuit 30 includes a resistance element 31, a voltage detection circuit 32, and a Zener diode 33 for overvoltage protection of the voltage detection circuit 32 for detecting the output voltage of the solar panel 10. The output voltage of the solar panel 10 is divided by the resistance element 31 and the Zener diode 33, and the voltage detection circuit 33 detects the voltage value V of the divided voltage, and the divided voltage information indicating the detected voltage value V is stored in the CPU 70. Output to.

  The solar charging circuit 30 further includes a backflow preventing diode 34 and an LDO (Low Drop Out) 35 which is one of linear regulators. The LDO 35 is controlled to be switched between driving and stopping by the CPU 70. In the present embodiment, the input voltage input from the solar panel 10 through the diode 34 is converted to a constant voltage of 4.0V, and a constant current output is output. Do. Note that the LDO 35 may be a constant voltage other than 4.0V.

Here, a configuration example of the LDO 35 will be described with reference to FIG. FIG. 3 is a circuit diagram of the LDO 35. FIG. 3 shows an example of the configuration of the LDO 35, and the configuration of the LDO 35 is not limited to that shown in FIG.
The LDO 35 includes an npn transistor 35a, resistance elements 35b and 35c, a reference voltage circuit 35d, and an amplifier 35e. However, the CPU 70 drives the amplifier 35e when driving the solar charging circuit 30, and stops the amplifier 35e when stopping the solar charging circuit 30.

When the amplifier 35e is stopped by the control of the CPU 70, the base current supplied from the amplifier 35e to the transistor 35a is approximately 0A, the transistor 35a is turned off, and the output current output from the solar charging circuit 35 is approximately 0A.
When the amplifier 35e is driven under the control of the CPU 70, the solar charging circuit 30 performs the following operation. The transistor 35a amplifies the emitter current supplied from the diode 34 to the emitter according to the base current supplied from the amplifier 35e to the base, and outputs the collector current from the collector. The collector voltage of the transistor 35a is divided by the resistance element 35b and the resistance element 35c, and the amplifier 35e is based on the voltage value Va of the divided voltage and the reference voltage value Vref of the reference voltage generated by the reference voltage circuit 35d. A current having a current value such that the voltage value Va becomes equal to the reference voltage value Vref is supplied to the base of the transistor 35a. Thus, the solar charging circuit 30 makes the input voltage constant and performs constant current output.

The capacitor 40 is disposed between the wiring from the LDO 35 to the switch 45 and the ground plate, and is charged using the power generated in the solar panel 10.
The switch 45 is provided in a current supply path from the LDO 35 to the secondary battery 50 and the circuit block B, and is turned on and off by the CPU 70. As the switch 45, for example, a bipolar transistor or a MOSFET can be used.

  The secondary battery 50 is to be charged within the charging operation guarantee range, and the temperature of the secondary battery 50 is detected and monitored by the charge control circuit 64. The secondary battery 50 is charged using the power generated in the solar panel 10 or charged using the power of the commercial power source. The secondary battery 50 supplies current to the circuit block B by discharging. The secondary battery 50 includes a lithium ion secondary battery.

The current detection circuit 55 detects the current supplied to the circuit block B, that is, the current value I of the consumption current of the circuit block B, and outputs consumption current information indicating the detected current value I to the CPU 70.
The rapid charging circuit 60 of the circuit block B includes an input unit 61 connected to the AC adapter 90, an npn transistor 62, a resistance element 63, and a charging control circuit 64. The charge control circuit 64 detects the temperature of the secondary battery 50 and outputs temperature information indicating the detected temperature to the CPU 70. The charge control circuit 70 controls on / off of the transistor 62, and thereby, charge control of the secondary battery 50 using the power of the commercial power source is performed.

  The CPU 70 controls the entire mobile phone 1. For example, the CPU 70, as shown in FIG. 4, based on the divided voltage information input from the voltage detection circuit 32, the temperature information input from the charge control circuit 64, and the consumption current information input from the current detection circuit 55. In addition, the LDO 35 is operated and stopped, and the switch 45 is turned on and off (see FIG. 5). However, the voltage threshold Vth is determined in consideration of whether the secondary battery 50 can be charged by power generation by the solar panel 10. Further, the temperature threshold Tth is determined based on the upper limit of the charging operation guaranteed range of the secondary battery 50. The current threshold Ith is determined so as to exceed a current value obtained by adding the output current of the LDO 35 and the output current of the capacitor 40.

The memory 80 is, for example, a semiconductor memory, and records various control programs and various application programs for the mobile phone 1. In the memory 80, for example, a program for the CPU 70 to execute control processing of the LDO 35 and the switch 45 whose operation flow is shown in FIG.
In the mobile phone 1 and the mobile phone 1a according to the second embodiment to be described later, the charging control circuit 64 detects and monitors the voltage of the secondary battery 50 so that the secondary battery 50 is not overcharged. The switches 45 and 62 are controlled.

<CPU operation>
Control processing of the LDO 35 and the switch 45 performed by the CPU 70 of FIG. 2 will be described with reference to FIG. FIG. 5 is a flowchart showing a procedure of control processing of the LDO 35 and the switch 45 performed by the CPU 70 of FIG. The CPU 70 reads a program for executing control processing of the LDO 35 and the switch 45 whose operation flow is shown in FIG. 5 from the memory 80, and executes the read program.

  The CPU 70 determines whether the voltage value V indicated by the divided voltage information input from the voltage detection circuit 32 is less than the voltage threshold Vth (step S1), and the secondary indicated by the temperature information input from the charge control circuit 64. It is determined whether the temperature T of the battery 50 is less than the temperature threshold Tth (step S3), and it is determined whether the current value I indicated by the current consumption information input from the current detection circuit 55 is less than the current threshold Ith (step S3). S5).

If the voltage value V is less than the voltage threshold Vth (S1: YES), the CPU 70 stops the LDO 35 and turns off the switch 45 (step S2). If the voltage value V is equal to or higher than the voltage threshold Vth (S1: NO) and the temperature T is lower than the temperature threshold Tth (S3: YES), the CPU 70 operates the LDO 35 and turns on the switch 45 (step S4). ).
If the voltage value V is equal to or greater than the voltage threshold Vth (S1: NO), the temperature T is equal to or greater than the temperature threshold Tth (S3: NO), and the current value I is less than the current threshold Ith (S5: YES), the CPU 70 causes the LDO 35 to operate. And the switch 45 is turned off (step S6). If the voltage value V is equal to or greater than the voltage threshold Vth (S1: NO), the temperature T is equal to or greater than the temperature threshold Tth (S3: NO), and the current value I is equal to or greater than the current threshold Ith (S5: NO), the CPU 70 The LDO 35 is operated and the switch 45 is turned on (step S7).

<Operation example of mobile phone>
An example of the operation of the mobile phone 1 in FIG. 2 will be described with reference to FIGS. However, in each of FIGS. 6 to 8, the horizontal axis is time. Further, in each of FIGS. 6 to 8, each of the divided voltage of the solar panel 10, the temperature of the secondary battery 50, and the current consumption of the circuit block B increases as it goes on the vertical axis.

[Operation example (1)]
FIG. 6 is a timing chart for explaining an operation example of the mobile phone 1 of FIG. However, the mobile phone 1 performs an operation in which the reception period and the sleep period appear alternately, and the circuit block B consumes a current less than the current threshold Ith during the sleep period and consumes a current greater than the current threshold Ith during the reception period. To do.

  The voltage detection circuit 32 detects a voltage value V of the divided voltage obtained by dividing the output voltage of the solar panel 10 and outputs divided voltage information indicating the detected voltage value V of the divided voltage to the CPU 70. Further, the charge control circuit 64 detects the temperature T of the secondary battery 50 and outputs temperature information indicating the detected temperature T to the CPU 70. The current detection circuit 55 detects the current value I of the consumption current of the circuit block B, and outputs consumption current information indicating the detected current value I of the consumption current to the CPU 70.

  Since the voltage value V of the divided voltage is less than the voltage threshold Vth until time T1, the CPU 70 stops the LDO 35 and turns off the switch 45. The circuit block B operates by receiving a current supply only from the secondary battery 50. As described above, when the power generated in the solar panel 10 is not sufficient, the LDO 35 is stopped and the switch 45 is turned off, so that the power stored in the secondary battery 50 is wasted in the resistance elements 35a and 35b. Therefore, it is possible to suppress a decrease in the remaining battery level of the secondary battery 50.

Since the voltage value V of the divided voltage after the time T1 is equal to or higher than the voltage threshold Vth and the temperature T of the secondary battery 50 is lower than the temperature threshold Tth until the time T2, the CPU 70 operates the LDO 35 and turns on the switch 45. The secondary battery 50 is charged using the electric power generated in the solar panel 10.
The voltage value V of the divided voltage after time T1 is equal to or higher than the voltage threshold Vth, and the temperature T of the secondary battery 50 is equal to or higher than the temperature threshold Tth after time T2. Since the current value I of the current consumption of the circuit block B is less than Ith from time T2 to time T3, the CPU 70 operates the LDO 35 and turns the switch 45 to ob. At this time, the capacitor 40 is charged using the electric power generated in the solar panel 10, and the secondary battery 50 is not charged.

  From time T3 to time T4, since the current value I of the current consumption of the circuit block B is equal to or greater than Ith, the CPU 70 operates the LDO 35 and turns on the switch 45. At this time, the secondary battery 50 is not charged because the current consumption of the circuit block B is large, but the circuit block B receives current supply from the secondary battery 50 and also receives current supply from the solar panel 10 and the capacitor 40. To do.

As a result, since the electric power generated in the solar panel 50 during the period when the temperature T of the secondary battery 50 is equal to or higher than the temperature threshold Tth is also used, the electric power generated in the solar panel 50 can be used efficiently. The reduction of the remaining battery level of 50 can be suppressed.
Further, since the power generated in the solar panel 10 during the period when the current consumption of the circuit block B is small is stored in the capacitor 40 and used by the circuit block B during the period when the current consumption of the circuit block B is large, the capacitor 40 is provided. Thus, the electric power generated in the solar panel 50 can be used more efficiently, and the reduction in the remaining battery level of the secondary battery 50 can be further suppressed.

The mobile phone 1 performs the same operation as the period from the time T2 to the time T3 in the period from the time T4 to the time T5, and the period from the time T5 to the time T6 is the same as the period from the time T3 to the time T4. Perform the operation.
[Operation example (2)]
FIG. 7 is a timing chart for explaining another operation example of the mobile phone 1 of FIG. However, the mobile phone 1 performs a call operation during the call period after the sleep period, and the circuit block B consumes a current less than the current threshold Ith during the sleep period and consumes a current greater than the current threshold Ith during the call period. .

  The voltage detection circuit 32 detects a voltage value V of the divided voltage obtained by dividing the output voltage of the solar panel 10 and outputs divided voltage information indicating the detected voltage value V of the divided voltage to the CPU 70. Further, the charge control circuit 64 detects the temperature T of the secondary battery 50 and outputs temperature information indicating the detected temperature T to the CPU 70. The current detection circuit 55 detects the current value I of the consumption current of the circuit block B, and outputs consumption current information indicating the detected current value I of the consumption current to the CPU 70.

Since the voltage value V of the divided voltage is less than the voltage threshold Vth until time T11, the CPU 70 stops the LDO 35 and turns off the switch 45. The circuit block B operates by receiving a current supply only from the secondary battery 50.
Since the voltage value V of the divided voltage is equal to or higher than the voltage threshold Vth after time T11 and the temperature T of the secondary battery 50 is lower than the temperature threshold Tth until time T12, the CPU 70 operates the LDO 35 and turns on the switch 45. The secondary battery 50 is charged using the electric power generated in the solar panel 10.

  After time T11, the voltage value V of the divided voltage is equal to or higher than the voltage threshold Vth, and after time T12, the temperature T of the secondary battery 50 is equal to or higher than the temperature threshold Tth. Since the current value I of the current consumption of the circuit block B is less than the current threshold Ith from time T12 to time T13, the CPU 70 operates the LDO 35 and turns the switch 45 to “O”. At this time, the capacitor 40 is charged by the electric power generated in the solar panel 10, and the secondary battery 50 is not charged.

  Since the current value I of the current consumption of the circuit block B is equal to or greater than Ith after time T13, the CPU 70 operates the LDO 35 and turns on the switch 45. At this time, the secondary battery 50 is not charged because the current consumption of the circuit block B is large, but the circuit block B receives current supply from the secondary battery 50 and also receives current supply from the solar panel 10 and the capacitor 40. To do.

[Operation example (3)]
FIG. 8 is a timing chart for explaining an operation example of the mobile phone 1 of FIG. However, the mobile phone 1 performs an operation in which the reception period and the sleep period appear alternately, and the circuit block B consumes a current equal to or greater than the current threshold Ith in both the sleep period and the reception period.
The voltage detection circuit 32 detects a voltage value V of the divided voltage obtained by dividing the output voltage of the solar panel 10 and outputs divided voltage information indicating the detected voltage value V of the divided voltage to the CPU 70. Further, the charge control circuit 64 detects the temperature T of the secondary battery 50 and outputs temperature information indicating the detected temperature T to the CPU 70. The current detection circuit 55 detects the current value I of the consumption current of the circuit block B, and outputs consumption current information indicating the detected current value I of the consumption current to the CPU 70.

Since the voltage value V of the divided voltage is less than the voltage threshold Vth until time T31, the CPU 70 stops the LDO 35 and turns off the switch 45. The circuit block B operates by receiving a current supply only from the secondary battery 50.
Since the voltage value V of the divided voltage after time T31 is equal to or higher than the voltage threshold Vth and the temperature T of the secondary battery 50 is lower than the temperature threshold Tth until time T32, the CPU 70 operates the LDO 35 and turns on the switch 45. The secondary battery 50 is charged using the electric power generated in the solar panel 10.

  After time T31, the voltage value V of the divided voltage is equal to or higher than the voltage threshold Vth, and after time T32, the temperature T of the secondary battery 50 is equal to or higher than the temperature threshold Tth. Since the current value I of the current consumption is greater than or equal to the current threshold value Ith in both the sleep period and the call period, the CPU 70 operates the LDO 35 and turns on the switch 45. At this time, the secondary battery 50 is not charged because the current consumption of the circuit block B is large, but the circuit block B receives current supply from the secondary battery 50 and also receives current supply from the solar panel 10 and the capacitor 40. To do.

<< Second Embodiment >>
The second embodiment of the present invention will be described below with reference to the drawings. The cellular phone 1 according to the first embodiment detects the current value of the consumption current of the circuit block B and controls the on / off of the switch 45. On the other hand, in the mobile phone 1a of the present embodiment, the CPU 70 determines the operation content of the circuit block B and controls the on / off of the switch 45. In the present embodiment, the same reference numerals are given to substantially the same components as those in the first embodiment, and the description thereof is applicable, and thus the description thereof is omitted in the present embodiment.

<Configuration of mobile phone>
A functional configuration of the mobile phone 1a according to the present embodiment will be described with reference to FIG. FIG. 9 is a circuit diagram of the mobile phone 1a of the present embodiment. It should be noted that the memory 80 has a program for executing the control process for the LDO 35 and the switch 45 shown in FIG. 11 instead of the program for executing the control process for the LDO 35 and the switch 45 shown in FIG. The program is stored.

  The CPU 70a controls the entire mobile phone 1a. For example, the CPU 70a, based on the divided voltage information input from the voltage detection circuit 32, the temperature information input from the charge control circuit 64, and the operation of the circuit block B including the CPU 70a, as shown in FIG. Are controlled, and the switch 45 is turned on and off (see FIG. 11). In the figure, “I <Ith operation” means an operation in which the circuit block B consumes a current having a current value less than the current threshold Ith, and “I ≧ Ith operation” means that the circuit block B is equal to or greater than the current threshold Ith. This means an operation that consumes a current of the current value.

<CPU operation>
Control processing of the LDO 35 and the switch 45 performed by the CPU 70a of FIG. 9 will be described with reference to FIG. FIG. 11 is a flowchart showing a procedure of control processing of the LDO 35 and the switch 45 performed by the CPU 70a of FIG. Note that the CPU 70a reads a program for executing control processing of the LDO 35 and the switch 45 whose operation flow is shown in FIG. 11 from the memory 80, and executes the read program.

  The CPU 70a determines whether the voltage value V indicated by the divided voltage information input from the voltage detection circuit 32 is less than the voltage threshold Vth (step S31), and the secondary indicated by the temperature information input from the charge control circuit 64. It is determined whether or not the temperature T of the battery 50 is lower than the temperature threshold Tth (step S32), and it is determined whether or not the circuit block B performs an operation that consumes a current having a current value lower than the current threshold Ith (step S35). In step S35, for example, the current value I of the current consumption of the circuit block B is stored in the memory 80 for each operation performed by the circuit block B, and the memory corresponding to the operation performed by the circuit block B is stored. This can be realized by comparing the current value stored in 80 with the current threshold Ith.

  If the voltage value V is less than the voltage threshold Vth (S31: YES), the CPU 70a stops the LDO 35 and turns off the switch 45 (step S32). If the voltage value V is equal to or higher than the voltage threshold Vth (S31: NO) and the temperature T is lower than the temperature threshold Tth (S33: YES), the CPU 70a operates the LDO 35 and turns on the switch 45 (step S34). ).

  If the voltage value V is equal to or higher than the voltage threshold Vth (S31: NO), the temperature T is equal to or higher than the temperature threshold Tth (S33: NO), and the circuit block B performs an operation of consuming a current having a current value less than the current threshold Ith. If so (S35: YES), the CPU 70a operates the LDO 35 and turns off the switch 45 (step S36). Further, the voltage value V is equal to or higher than the voltage threshold Vth (S31: NO), the temperature T is equal to or higher than the temperature threshold Tth (S32: NO), and the circuit block B performs an operation of consuming a current having a current value equal to or higher than the current threshold Ith. If (S35: NO), the CPU 70a operates the LDO 35 and turns on the switch 45 (step S7).

<Supplement>
The present invention is not limited to the contents described in the above embodiment, and can be implemented in any form for achieving the object of the present invention and the object related thereto or incidental thereto. .
(1) In each of the embodiments described above, the mobile phone has been described. However, the present invention is not limited to this, and an electronic device such as a mobile communication device other than the mobile phone may be used.

  (2) In each of the above embodiments, the current threshold Ith is fixed. However, the present invention is not limited to this. For example, the current value of the output current from the solar panel 10 is detected, and the detected current value of the output current is obtained. Based on this, the current threshold value Ith may be changed. Further, the current threshold Ith may be changed according to the operation by the circuit block B. In these cases, for example, based on the current value I of the current consumption by the circuit block B, the current threshold Ith is determined so that the secondary battery 50 is not charged when the temperature of the secondary battery 50 exceeds the guaranteed charging operation range. It is preferable.

(3) In each of the embodiments described above, the solar panel 10 has been described as an object, but other power generation mechanisms may be applied.
(4) In each of the above embodiments, the control processing (FIGS. 5 and 11) of the LDO 35 and the switch 45 has been described as being performed by the CPUs 70 and 70a. However, the present invention is not limited to this. 45 control processes (FIGS. 5 and 11) may be performed.

(5) The CPU 70 or 70a described in each of the above embodiments may record a program for executing control processing (FIGS. 5 and 11) of the LDO 35 and the switch 45 on, for example, a removable recording medium.
(6) In each of the above embodiments, the control line connected to the CPU 70 is branched and used for controlling the LDO 35 and the switch 45. However, the present invention is not limited to this. For example, separate control connected to the CPU 70 is used. A line may be used.

  The present invention can be used for an electronic device including a secondary battery.

1 Cellular Phone 10 Solar Panel 30 Solar Charging Circuit 35 LDO
40 capacitor 45 switch 50 secondary battery 55 current detection circuit 64 charge control circuit 70 CPU
80 memory

Claims (8)

An electronic device comprising a secondary battery and a charging means for charging the secondary battery,
Switch means provided in a current supply path from the charging means to the secondary battery;
A circuit block including a control unit and receiving current supply from the secondary battery and receiving current supply from the charging unit via the switch unit;
Temperature detecting means for detecting the temperature of the secondary battery;
Current detection means for detecting a current value of current consumption by the circuit block;
With
The control means includes
In the case where current can be supplied from the charging means to the secondary battery, and the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature,
An electronic apparatus comprising: turning off the switch means when a current value detected by the current detection means is less than a predetermined current value; and turning on the switch means when the current value is equal to or greater than the predetermined current value. The electronic device according to claim 1, further comprising: a capacitive element having one end connected between the charging unit and the switch unit of the current supply path, and the other end grounded. The charging means includes
Solar panels,
Solar charging means for making the output voltage of the solar panel constant and supplying current to the secondary battery and the circuit block;
The electronic apparatus according to claim 1, further comprising: An electronic device comprising a secondary battery and a charging means for charging the secondary battery,
Switch means provided in a current supply path from the charging means to the secondary battery;
A circuit block including a control unit and receiving current supply from the secondary battery and receiving current supply from the charging unit via the switch unit;
Temperature detecting means for detecting the temperature of the secondary battery;
With
The control means includes
In the case where current can be supplied from the charging means to the secondary battery, and the temperature detected by the temperature detecting means is equal to or higher than a predetermined temperature,
The switch means is turned off when the circuit block is operating to consume a current less than a predetermined current value, and the switch means is turned on when the circuit block is operating to consume a current greater than the predetermined current value. An electronic device characterized by The electronic device according to claim 4, further comprising: a capacitive element having one end connected between the charging unit and the switch unit of the current supply path, and the other end grounded. The charging means includes
Solar panels,
Solar charging means for making the output voltage of the solar panel constant and supplying current to the secondary battery and the circuit block;
The electronic apparatus according to claim 4, further comprising: A secondary battery; a charging means for charging the secondary battery; a switch means provided in a current supply path from the charging means to the secondary battery; and a control means for supplying current from the secondary battery. A circuit block that receives current supply from the charging means via the switch means, and a charge control method performed in an electronic device having the circuit block,
The control means includes
In the case where current can be supplied from the charging means to the secondary battery, and the temperature of the secondary battery is equal to or higher than a predetermined temperature,
A charge control method comprising: turning off the switch means when a current value of a current consumed in the circuit block is less than a predetermined current value; and turning on the switch means when the current value is equal to or greater than the predetermined current value. A secondary battery; a charging means for charging the secondary battery; a switch means provided in a current supply path from the charging means to the secondary battery; and a control means for supplying current from the secondary battery. A circuit block that receives current supply from the charging means via the switch means, and a charge control method performed in an electronic device having the circuit block,
The control means includes
In the case where current can be supplied from the charging means to the secondary battery, and the temperature of the secondary battery is equal to or higher than a predetermined temperature,
The switch means is turned off when the circuit block is operating to consume a current less than a predetermined current value, and the switch means is turned on when the circuit block is operating to consume a current greater than the predetermined current value. A charge control method characterized by:

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