JPH08297181A - Clock with night silencing function - Google Patents

Abstract

PURPOSE: To provide a clock with a night silencing function capable of being used without selectively limiting the C.MOS.IC and capable of reducing power consumption. CONSTITUTION: A switch circuit 50 and a light sensor 62 are connected in series, and the output signal of them is applied to the NAND gate 72 of a night silencing circuit 70. The light sensor 62 is connected to a power source and operated only when the brightness around a clock is detected. Even when a through current flows in the C.MOS constituting the night silencing circuit 70 in the middle-level brightness, it is limited to a very short time for brightness detection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a watch with a night-time stop ring function that stops the time signal when the surroundings of the watch become dark, and more particularly to a circuit configuration for connecting a light sensor for detecting the brightness and a power supply. Is.

[0002]

2. Description of the Related Art A conventional timepiece of this type has a circuit configuration as shown in FIG. That is, this timepiece is provided with the optical sensor 6 which is connected to the power supply voltage VDD through the resistor 2 and is made of Cds4 which is always energized. The voltage signal from between the resistor 2 and Cds4 is
It is applied to the NAND gate 10 in the night silencer circuit 8. The output signal of the NAND gate 10 has an H level when the clock periphery is bright and has an L level when the clock periphery is dark, and the output signal is applied to the NAND gate 12 of the next stage. A signal is also applied to the NAND gate 12 from a switch circuit 14 including a contact switch 16 that generates a one-shot pulse every hour and a monitor switch 18 that is turned on during a monitor operation. Further, the output of the NAND gate 12 is connected to the input terminal of the NAND gate 10 via the resistor 20 in order to obtain the Schmitt trigger pulse. At the output of the NAND gate 12, a pulse-like signal that changes from the H level to the L level is generated every hour when the clock is bright and at the time of monitor operation. The output signal of the NAND gate 12 is applied to a latch circuit 30 composed of the NAND gates 22 and 24, a resistor 26 and a capacitor 28. The latch circuit 30 responds to the signal from the NAND gate 12 and has a pulsed signal of H level at a predetermined timing. Output as a signal. When the signal from the latch circuit 30 rises to the H level, the control circuit 34 in the clock circuit 32 that controls the time display unit 38 and the time generation unit 36 starts a predetermined time operation and activates the time generation unit 36. , When the signal is at L level, it is set so that the time is not reported.

[0003]

Normally, the night noise stop circuit used in this type of timepiece is often composed of C / MOS / IC as a general-purpose product mass-produced by a component manufacturer. However, C / MOS as a general-purpose product
Some ICs have a circuit specification in which the inverters 40 to 46 are connected to the input side of the NAND gate 10 as shown in FIG. 3. If this is used, the following problems may occur. That is, in the case of a C-MOS-IC having a circuit of such specifications, for example, the inverter 40 is composed of the C-MOS shown in FIG. When such an inverter 40 is provided, the resistance values of the Cds 4 and the resistor 2 become substantially the same when the brightness becomes an intermediate level such as at dusk, and at this time, both the MOS-FETs are turned on. Therefore, a large through current IDD may flow. If such a large amount of electricity flows for a relatively long time,
Since the power consumption increases sharply, it is necessary to select and use a C-MOS-IC in which the inverters 40 to 46 are not provided on the input side of the NAND gate 10. Therefore, it is necessary to select and use C / MOS / IC having a certain specification, and there is a problem that the selection is complicated.

[0004] The present invention has been made in view of the above problems,
It is an object of the present invention to provide a timepiece with a stop ring function, which enables C / MOS / IC to be used without restricting selection and further reduces power consumption.

[0005]

SUMMARY OF THE INVENTION A watch with a night stop function according to the present invention comprises an optical sensor for detecting light and dark around the watch,
A switch circuit for instructing a time signal, a night silencer circuit for inputting a signal from the optical sensor and the switch circuit to a gate element and outputting a stop signal in response to both signals, and a signal for responding to the stop signal. In a watch with a night noise stop function consisting of a time signal circuit that stops time, the switch circuit and an optical sensor are connected in series, and the output signal and the signal from the switch circuit are input to the gate element of the night silence circuit. It is something that is done.

[0006]

In the night time stopwatch of the present invention, the switch circuit and the photosensor are connected in series, and their output signals are applied to the gate element of the night silencer circuit.
Therefore, the optical sensor is connected to the power source and operates only when the light and darkness around the timepiece is detected by the switch circuit. Therefore, even if a through-current flows through the C-MOS that configures the night silencer at night with an intermediate level of brightness, it can be kept for a very short time at the time of brightness detection. Therefore, unlike the conventional case, the power consumption is not extremely increased due to the specifications of the C / MOS / IC.
The power consumption can be made almost constant regardless of the specifications of the IC. Moreover, since the optical sensor is not energized at all times, the power consumption can be further reduced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a circuit diagram of a night watch with a ringing stop function according to an embodiment of the present invention. A switch circuit 50 is composed of a contact switch 52 for generating a one-shot pulse at every hour, a time switch 54 for switching on / off at the time of report, and a monitor switch 56 operated at the time of monitor operation. . The contact switch 52 and the time switch 54 are connected to each other in series, connected to the power supply voltage VDD, and further connected to the ground via a capacitor 58 and a resistor 60 which are connected in parallel to each other. Also, similarly to this, the monitor switch 56
Is also connected to the power supply voltage VDD and the capacitor 58
And a resistor 60 to the ground.

Reference numeral 62 denotes an optical sensor made of Cds 64. In this embodiment, one end is connected to the connection point of the contact switch 52 and the monitor switch 56, the condenser 58 and the resistor 60 via the time switch 54, and one end of the other is connected. The other end is connected to the ground via a capacitor 66 and a resistor 68 connected in parallel.

Reference numeral 70 denotes a night silencer circuit, which is a NAND gate 7 whose inputs are connected to one end and the other end of the Cds 64, respectively.
2 and NAND gates 74 and 7 for inputting the output signal thereof
6, a latch circuit 82 including a resistor 78 and a capacitor 80, and a resistor 84 provided between its output end and one input end of the NAND gate 72.

Reference numeral 84 is a time signal circuit, which is a melody circuit 8
6, a time generation unit 88, and a time striking mechanism 90. The melody circuit 86 controls the operation / stop of the time generation unit 88 in response to a stop signal from the latch circuit 82 in the night silencer circuit 70.

Next, the operation of the night time stopwatch with the above structure will be described. First, as shown in FIG.
When all of the contact switch 52, the report switch 54, and the monitor switch 56 are off, the Cds 64 in the optical sensor 62 is cut off from the power supply voltage VDD. Here, the contact switch 52 together with the time switch 54
Or, when the monitor switch 56 is turned on, Cds
64 is connected to the power supply voltage VDD via these switches. Since the resistance value of the Cds 64 is set to be small when it is bright and large when it is dark, a voltage signal of H level is added to one input end of the NAND gate 72 when it is bright and L level when it is dark. A pulsed voltage signal of H level corresponding to the turning on of each switch is applied to the other input terminal. Therefore, the output of the NAND gate 72 is L when it is bright.
A level pulse is generated and kept at H level when dark. In this way, when the L level pulse is output from the NAND gate 72, the latch circuit 82 applies the H level pulse at a predetermined timing to the melody circuit 86, and the melody circuit 86 performs the timekeeping operation. Further, when the signal from the NAND gate 72 is held at the H level, the output of the latch circuit 82 is also held at the L level, and the melody circuit 86 to which the output is input maintains the time stop state.

As described above, in the present embodiment, the Cds6 is provided only while the contact switch 52 or the monitor switch 56 is in the ON state in order to detect the light and darkness around the timepiece.
Since 4 is connected to the power supply voltage VDD, the NAND gate 7
The time the voltage signal is applied to the two inputs is very short. Therefore, even when the brightness around the timepiece is at an intermediate level and the resistance values of the Cds 64 and the resistor 68 are the same when detecting the brightness and darkness, only when the contact switch 52 or the monitor switch 56 is in the ON state. Such a state is maintained. Therefore, even if the inverters 40 to 46 as shown in FIG. 3 are provided on the input side of the NAND gate 72,
The through current flowing through this inverter flows for a very short time. As a result, the power consumption does not increase as compared with the case where the inverter is not provided on the input side of the NAND gate 72, and it is necessary to select the C / MOS / IC in which the inverter is not provided on the input side of the NAND gate 72. Disappears.

The contact switch 52 in the switch circuit 50 in this embodiment is mechanically turned on and off. Instead of this, a microcomputer is used to send a controlled signal output from the microcomputer. It can also be configured to feed Cds64.

[0014]

According to the present invention, the switch and the optical sensor are connected in series and their output signals are input to the gate element of the night silencer. Even if the inverter is provided in the circuit portion for inputting the voltage signal from the sensor, the through current flows only for a very short time. Therefore, there is almost no difference in the amount of power consumption depending on the presence or absence of the inverter, and the C / MOS / IC provided with the inverter can be used.

Further, since the light sensor is energized only when the light and dark are detected, it is possible to reduce the power consumption as compared with a circuit which is always energized.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a timepiece with a night noise stop function according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a conventional timepiece with a night noise stop function.

FIG. 3 is a diagram showing a circuit configuration when an inverter is provided on the input side of the NAND gate shown in FIG.

FIG. 4 is a circuit diagram showing a configuration of an inverter shown in FIG.

[Explanation of symbols]

 50 switch circuit 62 optical sensor 70 night silence circuit 84 reporting circuit

Claims (1)

[Claims] 1. A light sensor for detecting light and darkness around a timepiece, a switch circuit for indicating time signal, a signal from the light sensor and the switch circuit is input to a gate element, and a stop signal is generated in response to both signals. In the night time stopwatch with a night silencer circuit that outputs the time signal and a time signal circuit that stops the time signal in response to the stop signal, the switch circuit and the optical sensor are connected in series, and the output signal A watch with a silence function at night, wherein a signal from the switch circuit is input to a gate element of the silencer circuit at night.