JPH07122674B2 - Clock with built-in power generation means - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention belongs to the field of electronic timepieces equipped with internal power generation means for CMOS integrated circuit technology applications.

[Outline of Invention]

INDUSTRIAL APPLICABILITY The present invention relates to an internal power generation means, particularly a solar cell timepiece including a solar cell and an electronic timepiece body, and a charge storage unit for operating the electronic timepiece body immediately after light irradiation, and a long time when light irradiation is stopped. A signal of the voltage control unit, which has a second charge storage unit for driving the timepiece body and acts to limit the upper limit of the driving voltage, is used for the voltage control of the first charge storage unit side. By supplying the inverted signal as a voltage control signal to the second charge storage unit side, the voltage is supplied to the second charge storage unit side while the voltage of the first charge storage unit side is sufficient and the solar cell output becomes unnecessary. The solar cell output is applied to efficiently accumulate electric charges, and when the light quantity is low, the first and second electric charge accumulators are connected to enable a long-time clocking function. .

[Conventional technology]

Conventionally, for example, the solar cell timepiece disclosed in JP-A-60-3577 uses a high-capacity electric double layer capacitor as a backup power source for the solar cell, and when the terminal voltage of the capacitor is lower than a set voltage. When the capacitor is discharged (that is, when the capacitor is discharged), the switch element is turned off to stop the supply of the backup power supply to the clock circuit to prevent useless discharge after the time stop, and shorten the recharge time. Further, in the solar cell timepiece disclosed in JP-A-60-111179, when the oscillation of the timekeeping circuit is stopped, the power supply from the secondary battery is turned off by a switch element to cause unnecessary discharge after the timekeeping is stopped. This will prevent and reduce the recharge time.

However, in the above-mentioned conventional technique, there is a problem that the power generation is stopped when the sunlight disappears and the timekeeping function stops.

[Problems to be Solved by the Invention] In view of the above problems, the timepiece with built-in power generation means of the present invention does not require a disposable battery, performs stable operation for a long time, and generates power immediately after manufacturing or even in a state where it is not charged for a long time. An object of the present invention is to provide a timepiece with a built-in power generation means that can immediately start a timekeeping operation when the means starts power generation.

[Means for Solving the Problems] A timepiece built-in timepiece of the present invention includes a timepiece load, an internal power generation means serving as a power source of the timepiece load, and a first charge storage means for storing the voltage output of the power generation means. In a watch with a built-in power generation means, which includes a backflow prevention means for preventing reverse current charging to the first charge storage means, a first switch element electrically connecting the first charge storage means and the power generation means. A second switch element for electrically connecting the timepiece load and the power generating means; a first switch element connected in series with the second switch element and in parallel with the timepiece load; A second charge storage means having a smaller charge storage amount than the first charge storage means, and one end connected to a connection point between the timepiece load and the second switch element, and the other end connected to the first charge storage means and the first charge storage means. Connection with switch element And a voltage control means for controlling the switch element, wherein the voltage control means includes the first switch element when the operation of the timepiece load is stopped. Is turned off to turn on the second switch element, the first switch element is turned on and the second switch element is turned off when the voltage across the second charge storage means is higher than a predetermined voltage, and , The first switch element is turned off when the voltage across the terminal is lower than the predetermined voltage.
The switch element is turned on, and when the voltage across the first charge storage means is higher than the predetermined voltage and the voltage across the second charge storage means is lower than the predetermined voltage, the third charge
The switch element is turned on.

[Examples] Hereinafter, examples of the present invention will be described in detail.

FIG. 1 is a conceptual diagram of the basic configuration of the present invention. In the figure, 1 is a solar cell, 2 is a voltage control unit, 3 is a watch body supply voltage dividing unit, 4
Is a watch body, 5 is an auxiliary charge storage unit, 6 is a charge storage unit, 7 to
Reference numeral 9 is a voltage control element, 10 is a signal converter, and 11 is a backflow prevention diode.

First, as the intended condition of the system, the charges of the charge storage portions 5 and 6 are set to zero. In this state, when the solar cell 1 is irradiated with light, a voltage is applied to the voltage controller 2 and the voltage controller becomes active. Almost at the same time, the solar cell voltage is also applied to one end of the voltage control element 7 through the backflow prevention diode 11. However, there is no electric charge in the timepiece body of 4 and the auxiliary charge accumulation section of 5 connected in parallel with the timepiece body, so that the output of the timepiece side voltage dividing section 3 is the voltage control element 7 driven by the voltage control section.
Goes in the direction of turning on enough. Then, a voltage is applied to the timepiece body 4 and the auxiliary charge storage section 5 via the voltage control element 7.

Here, if the capacity of the auxiliary charge storage unit 5 is set to a value at which the auxiliary charge storage unit 5 is charged in a few seconds at most, a sufficient voltage is applied within a few seconds after the voltage is applied, and the timepiece body 4 starts operating. At this time, the voltage division unit 3 also divides the auxiliary charge storage unit voltage, and a signal is applied to the control loop of the voltage control unit 2.

When the system rises from the previously set initial state, the voltage control unit output is in a state in which the voltage control element 7 is sufficiently turned on, that is, a sufficiently high potential is output. However, when the operation progresses to the above conditions, the voltage is gradually increased. Its output voltage begins to drop. When the voltage of the auxiliary charge storage unit 5 reaches the voltage value determined by the voltage dividing unit of 3, the voltage control element 7 no longer needs to be turned on, so that the output of the voltage control unit is sufficiently low and the voltage control element 7 is turned off. It goes down.

On the other hand, the signal conversion unit 10 receives the low potential output of the voltage control unit and operates so that the voltage control element 9 that is in series with the charge storage unit 6 is turned on. Therefore, while the voltage control unit 2 is turning off the control element 7, the solar cell output is entirely used for charging the charge storage unit 6.

When the timepiece body 4 continues to operate and the voltage of the auxiliary charge storage unit 5 decreases, the voltage control element 7 turns on again, and conversely, the voltage control element 9 turns off. Thereafter, the series of operations described above is repeatedly performed, so that the electric charge is stored in the charge storage unit 6.

When the electricity is sufficiently stored and the output of the solar cell is drastically reduced or disappeared, the voltage control element 8 is turned on by the light detection operation signal performed by the timepiece body 4. By this operation, the voltage supply to the timepiece body 4 is switched to the side of the large-capacity charge storage section 6, and the timepiece operation is guaranteed.

When the solar cell output is output again while the timepiece operation is continued by being supplied with the voltage from the charge storage section 6, the voltage control element 8 is turned off by the photodetection operation of the timepiece body 4. At this time, if the voltage of the charge storage unit 6 is higher than the set voltage of the voltage control unit 2, the voltage of the auxiliary charge storage unit 5 also exceeds the set voltage, so the voltage control element 7 is turned off and 9 is turned on. The solar cell output is used for charging the storage unit 6.

Conversely, when the voltage of the charge storage unit 6 is low, the voltage control element 7
Is fixed to ON and 9 is fixed to OFF, and the solar cell output is used for charging the timepiece side until the voltage of the auxiliary charge storage unit 5 reaches the set voltage of the voltage control unit 2, and then the charge storage unit 6 is charged.
Switch to charging to.

FIG. 2 is a specific circuit example of the present invention. In the figure, 1 is a solar cell, 2 is a voltage control unit, 3 is a voltage dividing unit, 4 is a watch body, 5 is an auxiliary charge storage unit, 6 is a charge storage unit 7 to 9 are voltage control elements, and 10 is a signal conversion unit. is there. In this embodiment, thirteen OP amplifiers and twelve reference voltage generating circuits are used as the second voltage control unit configuration. The voltage control elements 7 to 9 use N-channel enhancement MOSFETs (hereinafter abbreviated as Nch FETs).

The auxiliary charge storage unit 16 is a tantalum or aluminum electrolytic capacitor, and the charge storage unit 6 is an electric double layer capacitor 17
Is used.

Two voltage dividing capacitors 14 and 15 are used for the voltage dividing section 3 so that no current flows.

The signal conversion unit of 10 is a P channel depletion MOSFET 18
It consists of Nch FET19.

By the way, for the light detection operation performed by the timepiece 4, the output of the reference voltage generation circuit 12 driven directly by the solar cell 1 is used in this embodiment.

Since the concrete system operation outline in the present embodiment has already been explained by the above-mentioned operation, only the explanation of the operation requiring supplement will be described.

Pch depletion MOSFET, Nch in 10 signal converter configuration
The use of (enhancement) MOSFET provides the following advantages in system operation.

(1) It is necessary to detect when the voltage control element 7 is turned off as an essential condition of the signal conversion unit. In that point, if an inverter with Pch depletion MOSFET and Nch MOSFET is used, the inversion threshold voltage of the inverter can be set near the gate threshold voltage of the Nch MOSFET by limiting the current of the Pch depletion MOSFET.

(2) Another advantage is brought about by the operation of (1) above. That is, the operating current of the inverter is determined by the constant current source of the Pch depletion MOSFET. This is a circuit
This means that the operating current can be reduced.

The above-described embodiments are merely a few specific examples for implementing the present invention, and can be realized by various element configurations.

〔The invention's effect〕

According to the present invention, the voltage control means is configured to turn off the first switch element and turn on the second switch element when the operation of the timepiece load is stopped, so that the voltage control means is charged after manufacturing or for a long time. If the voltage is generated in the power generation means when the timepiece is not stopped and the voltage is generated in the power generation means, the generated voltage is supplied to the timepiece load and the second charge storage means having a small capacity connected in parallel therewith via the second switch element. Since the voltage is applied, the second charge storage means is charged in a short time, and as a result, the start of the timepiece load can be started in a short time.

Further, when the voltage across the second charge storage means is higher than a predetermined voltage, the first switch element is turned on and the second switch element is turned off, and when the voltage across the second charge element is lower than the predetermined voltage, the first switch element is turned on. Since the element is turned off and the second switch element is turned on, it is possible to charge the power generation amount of the power generation means to the first charge storage while operating the clock load by the voltage of the second charge storage means. This makes it possible to efficiently charge the first charge storage means, which requires a long time.

Further, the third switch element is turned on when the voltage across the first charge storage means is higher than the predetermined voltage and the voltage across the second charge storage means is lower than the predetermined voltage. Even when the power generation voltage decreases, the timepiece load can be driven by the voltage of the first charge accumulating means, so that the reliability of timepiece driving can be improved even when the amount of power generation changes significantly. .

[Brief description of drawings]

FIG. 1 is a conceptual diagram of the basic configuration of the solar cell timepiece of the invention, FIG.
The figure is a circuit diagram of a concrete example of a solar cell timepiece. 1 ... Solar cell 2 ... Voltage control unit 3 ... Voltage division unit 4 ... Clock body 5 ... Auxiliary charge storage unit 6 ... Charge storage unit 7-9 ... Voltage control element 10 ... Signal conversion unit 11 ...... Backflow prevention diode

Claims (1)

[Claims] 1. A timepiece load, an internal power generation means serving as a power source of the timepiece load, a first charge storage means for storing a voltage output of the power generation means, and a reverse current charge to the first charge storage means. In a timepiece with built-in power generation means having a backflow prevention means for preventing, a first switch element electrically connecting the first charge storage means and the power generation means, and the timepiece load and the power generation means are electrically connected. A second switch element to be connected, and a second charge storage means connected in series with the second switch element and connected in parallel with the watch load and having a smaller charge storage amount than the first charge storage means. A third end whose one end is connected to a connection point between the watch load and the second switch element and the other end is connected to a connection point between the first charge storage unit and the first switch element. A switch element and the switch Voltage control means for controlling a switch element, the voltage control means turning off the first switch element and turning on the second switch element when the operation of the timepiece load is stopped. , When the voltage across the second charge storage means is higher than a predetermined voltage, turning on the first switch element and turning off the second switch element, and when the voltage across the second voltage is lower than the predetermined voltage. The first switch element is turned off and the second switch element is turned on.
The switch element is turned on, and when the voltage across the first charge storage means is higher than the predetermined voltage and the voltage across the second charge storage means is lower than the predetermined voltage, the third charge
A watch with a built-in power generation means, which is configured to turn on the switch element.