JPS5831111Y2 - Clock with battery life warning display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a battery life warning display method in an electronic watch equipped with an electro-optical display device.

An electronic watch that uses a battery as an energy source loses its function as a clock when its battery life ends, so it is necessary to give advance notice of when the battery life will end.

However, a so-called battery life warning display has been implemented in which a voltage detection circuit that uses the threshold level of a field effect transistor is operated to sample the voltage of the battery, thereby detecting a certain voltage drop state and displaying a warning. This battery life warning display warns the user that the battery life is nearing its end and urges the user to replace the battery.A display method with a high warning effect is desirable, and an electro-optical display device is preferable. In digital electronic watches equipped with such a device, a system is used in which when the voltage drop state is detected, part or all of the display including the time display is put into an abnormal display state such as a blinking display.

However, the voltage detection circuit consumes current during sampling, so in order to reduce the current consumption, it is necessary to lengthen the cycle of the sampling signal. If sampling is performed under adverse conditions such as when resistance is increasing or when a lighting lamp is on, an apparent voltage drop will be detected and a false battery life warning will be displayed. However, if the period of the sampling signal is made longer, there is a disadvantage that the false display of battery life warning will continue until it is corrected by the next sampling signal. The period of the sampling signal was shortened.

SUMMARY OF THE INVENTION The object of the present invention is to provide a timepiece with a battery life warning display that eliminates the above-mentioned drawbacks, allows a longer sampling period during normal operation, and allows prompt correction in the event of a malfunction.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an electronic timepiece according to the present invention, in which 1 is a crystal oscillator, 2 is an oscillation circuit, 3 is a frequency dividing circuit, and 4 is a timekeeping circuit, including a minute counter 4a, an hour counter 4b, It is composed of a day counter 4c and a day counter 4d.

5 is a decoder, 6 is a display control circuit, 7 is a driver circuit, 8 is an electro-optical display device, a minute display section 8a, an hour display section 8b, and a date display section 8cs corresponding to each counter of the timekeeping circuit 4. It has a day of the week display section 8d.

9 is a digit selection switch for time adjustment; 10 is a correction switch for correcting the digit selected by the digit selection switch 9;

A correction signal control circuit 11 receives operation signals from the switches 9 and 10 and supplies signals to the normal display terminal ND, time correction terminal Ca%Cd, and correction signal terminal PC.

Reference numeral 12 denotes a battery, which supplies a power supply voltage VDIA' to each circuit.

Furthermore, 13 is a voltage detection circuit υ that uses the threshold level of a field effect transistor, and periodically checks the voltage of the battery 12 using a sampling signal ps.
When the battery voltage falls below a preset value of 7X, a warning signal of logic 11 level is generated at the output terminal O.

Reference numeral 14 denotes a sampling signal switching circuit, which selects two types of sampling signals P 1 sP2 with different periods supplied from the clock circuit 4 and the frequency dividing circuit 3 according to the logic state of the control terminal C, and converts the sampling signal ps into a voltage. Supplied to the detection circuit 13.

15 is an AND gate that controls the battery life warning display.

In the above configuration, the crystal resonator 1, the oscillation circuit 2, the frequency dividing circuit 3, the clock circuit 4, the decoder 5, the driver circuit 11, and the electro-optical display device 8 constitute a well-known digital electronic clock, and the correction signal In the normal display state in which the control circuit 11 specifies the normal display terminal ND, the display control circuit 6
maintains all the display sections of the electro-optical display device 8 in a normal display state.

Next, to explain the time adjustment operation, the digit selection switch 9
When you operate once, the time adjustment terminal C is activated by the operation signal.
a is specified, and as a result, the minute counter 4a of the timekeeping circuit 4
is in the correctable state, and the digit is selected, and the electro-optical display device 80 minute display section 8a enters a blinking display state according to the designation of the display control circuit 6, indicating that it is in the correctable state. In this state, when the correction switch 10 is operated, a number of correction signals corresponding to the number of operations of the correction signal terminal PC of the correction signal control circuit 11 are generated, and the counter 4a which is in the correction possible state is corrected.

This state of correction can be monitored by the minute display section 8a.

Similarly, each time the digit selection switch 9 is operated, the time correction terminals Cb*Cc-Cd of the correction signal control circuit 11 are sequentially specified, and as a result, the hour counter 4b and the day counter 4c
The day counters 4 and 4 become modifiable in sequence, and only the corresponding display sections become blinking.

By operating the modification switch 10, each counter in the modification designated state can be modified.

Each time correction terminal Ca-Cd of the correction signal control circuit 11
As indicated by the dotted line, the normal display state ND is restored after a certain period of time by a timer (not shown).

Next, the battery life warning display will be explained.

In this embodiment, the sampling signal P1 supplied from the clock circuit 4 is set to a 24-hour period, and the sampling signal P2 supplied from the frequency dividing circuit 3 is set to a 10-second period pulse. When terminal C is logic 10'', signal P1 is output, and when terminal C is logic Jl, signal P is output.
2 are respectively supplied to the voltage detection circuit 13 as sampling signals ps.

Therefore, the voltage detection circuit 13 detects the sampling signal P while the voltage of the battery 12 has not decreased to its operating level.
Since the output terminal 0 does not generate a warning signal and continues to be held at logic 101, the battery life warning display is not performed. When the sampling operation of the voltage detection circuit 13 is performed when the voltage drops due to poor conditions such as low temperature or illumination lamp lighting, a warning signal is generated at the output terminal O, and at this time, the correction signal control circuit 110 If the normal display terminal ND is specified, the output terminal of the AND gate 15 becomes logic 11", and the display control circuit 6
operates and all the display parts of the electro-optical display device 8 flash and display a battery life warning.At the same time, the sampling signal is switched to P2 by setting the control terminal C of the sampling signal switching circuit 140 to logic +111. .

Due to this switching operation, the sampling operation of the stain pressure detection circuit 13 has a cycle of 10 seconds.75 If the cause of the voltage drop is due to the life of the battery 12, the warning signal is maintained and the battery life warning display is maintained. .

On the other hand, if the cause of the voltage drop is temporary due to adverse conditions such as lighting of a lighting lamp, the warning signal will be corrected by the next sampling operation when the voltage level returns to the operating level of the voltage detection circuit 13 or higher, and the battery life will end. Warning display will be stopped.

Then, the sampling signal switching circuit 14 switches the sampling signal to Pl so that the control terminal C returns to logic 101.
and return to normal operation.

Also, during the battery life warning display state, the digit selection switch 9 is operated to select the time correction terminals Ca to Cd of the correction signal control circuit 11.
When specified, the output terminal of the AND gate 15 connected to the normal display terminal ND becomes logic °'01, the battery life warning display is stopped, and the display section specified by the time correction terminal blinks instead, indicating the correction digit selection. Perform display.

When the correction signal control circuit 11 returns to the normal display state, the Nl) terminal becomes logic "11" and the battery life warning display is restarted.

Incidentally, the sampling signals P1 and P2 can each use periodic pulses other than those in this embodiment, if necessary, and the sampling timing of the sampling signal P1 in this embodiment is as follows, considering the above-mentioned adverse conditions.
Avoid sleeping hours when the person carrying the device may take it off their wrist, and ensure that the device is on the phone, the temperature is relatively high, and the lighting lamp does not need to be turned on. to 6 p.m. The car is heavy.

As mentioned above, in this invention, by using two types of sampling signals with different periods, the current consumption during normal sampling operation can be reduced, and malfunctions can be corrected immediately. Moreover, since the timing of normal sampling can be determined taking into account the above-mentioned adverse conditions, it is possible to provide a watch with a highly reliable battery life warning display. Since the battery life warning display on the device is displayed only in the normal display state, the flashing display, which is highly effective as a warning display, can be used both as a battery life warning display and as a correction digit selection display. It is now possible to adjust the time even when the battery life warning is displayed, and for the same reason, even in electronic watches equipped with functions such as alarms and timers, the alarm time, etc. can be adjusted even when the battery life warning is displayed. This makes it possible to provide a watch with a battery life warning display that is highly reliable and easy to use for the wearer.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an electronic timepiece according to the present invention. 4... Timing circuit, 6... Bale indication control circuit,
8... Electro-optical display device, 11...-
Correction signal control circuit, 12...Battery, 13...
... Voltage detection circuit, 14... Sampling signal switching circuit.

Claims (1)

[Scope of utility model registration request] In an electronic watch that includes a battery, an electronic circuit, a time display device, a voltage detection circuit that periodically detects the voltage level of the battery through a sampling operation, and a battery life display means that is controlled by an operation signal of the voltage detection circuit, A sampling signal switching circuit is provided, which inputs a plurality of signals having different cycles generated by the electronic circuit, selects the selected signals according to the logic state of the control terminal, and supplies the selected signals as sampling signals to the voltage detection circuit. 9. A watch with a battery life warning display, characterized in that by supplying an operation signal of the voltage detection circuit to a control terminal of the voltage detection circuit, the voltage detection circuit performs sampling operations at different cycles depending on its output state.