JPS6036594B2 - alarm device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an alarm device used in electronic wristwatches and the like.

Currently, electronic wristwatches are being developed that have an alarm function in addition to a time display function by incorporating an alarm device using a speaker or a buzzer.

However, some conventional alarm devices are known that can change the sound quality, but the sound pressure (loudness of the sound)
However, the pronunciation for the words was single and could not be pronounced according to the environment.

In other words, the appropriate volume is different between a noisy outdoor setting and a quiet indoor setting such as a movie theater, but this adjustment cannot be made. -Therefore, we developed an alarm system that can produce different sound pressures depending on the environment. It is necessary to develop a system for

The first possible method for this is to switch and control the driving voltage of the alarm device itself, but this requires three-value potentials, making the power supply circuit complicated. This invention has been made based on the above circumstances, and aims to provide an alarm device that can select and switch the sound pressure of a sounding body with a simple circuit configuration using MOS transistors that can be integrated. . Hereinafter, the present invention will be specifically explained based on illustrated embodiments.

In the figure, reference numeral 1 denotes a pulse generation circuit, which outputs clock pulses of a predetermined period in response to an alarm time detection signal from a clock device 2. It should be noted that the pulse generating circuit 1 is constituted by a gate control circuit that gate-controls a signal from a frequency dividing circuit of the timepiece device 2, or an oscillation circuit such as an astable multipipulator. The clock pulse of the pulse generating circuit 1 is transmitted to the transfer line switching circuit 4 via the drive circuit 3.
sent to. This transfer line switching circuit 4 includes transmission gates 5a and 5 composed of MOS transistors.
In addition, the on-resistance of the transmission gate 5a is set larger than the on-resistance of the transmission gate 5b. The above transmission gates 5a, 5
In order to make the on-resistance of b different, the length or length of the channel of the MOS transistor may be changed. 6
is a control switch for switching and controlling the transfer lines 4a and 4b, and the operation signal of this control switch 6 is F.
The output signal of F (flip-flop circuit) 7 is inverted.

The output signal of FF7 is supplied to the gates of the P-channel MOS transistor of transmission gate 5a and the N-channel MOS transistor of transmission gate 5b, and is also supplied to the gates of the N-channel MOS transistor of transmission gate 5a and the P-channel MOS transistor of transmission gate 5b via inverter 8. Channel M
It is supplied to the OS transistor, and selectively controls transmission gates 5a and 5b to turn on and off. F
The output signal of F7 is further supplied to a display section (not shown), which displays transfer line selection information. A signal passing through either of the transmission gates 5a, 5b is applied to the base of an N-channel transistor 9. The transistor 6 is turned on when the signal applied via the transfer line 4a or 4b is at high level (OV). A coil 10 and a vibrating body 11 including a piezoelectric element are connected in parallel to the collector of the transistor 9, and a voltage "Vo" is applied to the emitter of the transistor 9.

Further, a diode 12 for reverse voltage compensation is connected between the emitter and the base of the transistor 9. Next, the operation of the above circuit will be explained.

Assuming that the output signal of the FF 6 is now at a low level (-Vo), the transmission gate 5a is on, and the clock pulse from the pulse generating circuit 1 is supplied to the transistor 9 via the transfer line 4a. Therefore, the transistor 9 receives the clock pulse at a high level (O
V), the potential on the collector side of the transistor 9 becomes "1Vo".However, when the clock pulse reaches the low level (1V), the transistor 9 is turned off and no collector current flows. Therefore, due to this rapid change in the collector current, a high voltage is induced in the coil 10', and the vibrating body 11 is driven by this induced voltage to generate sound.
Next, operate the control switch 7 to change the output signal of FF6 to /
- When set to the high level (OV), the clock pulse from the pulse generating circuit 1 is supplied to the transistor 9 via the transfer line 4b, and the vibrating body 11 similarly performs the sound generation operation. However, in this case, since the resistance value of the transfer line 4b (the resistance value of the transmission gate 5b) is smaller than the resistance value of the transfer line 4a, the base current of the transistor 9 increases. Therefore, transistor 9
The amount of change in the collector current when the transfer line 4a is turned off also increases, and as shown in FIG. 2, the voltage induced in one coil becomes larger than when the transfer line 4a is selected. Since the sound pressure of the sound generated by the vibrating body 11 depends on the magnitude of the driving voltage, in this case, the vibrating body 11 produces sound at a higher sound pressure than when the transfer line 4a is selected. In addition,
The diode 12 cuts off the negative voltage at a constant value so that even if a reverse voltage is applied to the transistor 9, it will not damage the transmission gates 5a, 5b, etc. In the above embodiment, the on-resistance values of the transmission gates are made different, but next we will show an example in which the on-resistance values are controlled by the number of transmission gates.

In the embodiment shown in FIG. 3, two transmission gates 5a, 5a' are arranged in series on one transfer line 4a, and one transmission gate 5b is arranged on the other vehicle germ transfer line 4M. Here, even though the transmission gates 5a, 5a' and 5b have the same on-resistance, they have the same effect on the circuit as the transmission gates 5a, 5a' and 5b which have two different on-resistances. Similarly, in the embodiment shown in FIG. 4, transmission gates 5a, 5b, 5b' are arranged for three transfer lines 4a, 4b, 4b', respectively, and one control is provided to the transmission gates 5a, 5b, 5b'. The transfer line 4a and the transfer lines 4b and 4b' are selectively used by a signal.

For this reason, each transmission gate 5a, 5b, 5
Even though b' has the same on-resistance, two transmission gates 5a and 5a, 5b' having different on-resistances are selected in the circuit. Incidentally, in the above embodiment, the transmission gate is composed of a CMOS transistor, but it goes without saying that it may be composed of a single channel MOS transistor.

Further, the sound pressure of the sounding body can be set to an arbitrary number of stages, and further control may be added that does not drive the sounding body. FIG. 5 shows this example, where the control switch 7
provides a control signal to each transmission gate 5a, 5b, and 5c via the shift register 13 to control switching, and it is also possible to select not to drive the sounding body. Further, in the above embodiment, a buzzer using a piezoelectric element was used as the sounding body, but a speaker can be used as well.

As described above, the present invention provides a transmission gate means having different resistance values, which is composed of MOS transistors, between a pulse generation circuit and a high voltage generation circuit to which a pulse signal from the pulse generation circuit is supplied. Since the sound pressure is controlled by switching and controlling the circuit, the circuit configuration is simple and integration is possible. Effective.

[Brief Description of the Drawings] Fig. 1 is a circuit configuration diagram showing an embodiment of the present invention, Fig. 2 is a diagram showing the relationship between clock pulses and induced voltage, and Figs. 3 to 5 are diagrams showing other embodiments of the invention. FIG. 2 is a circuit configuration diagram of main parts showing an embodiment of the present invention. 1...Pulse generation circuit, 5a, 5b, 5c.・
・．． ...Transmission gate, 7...Control switch, 9 """ transistor, 10...Coil, 11...
...Vibrating body. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. A pulse signal generation circuit that outputs a pulse signal of a predetermined period, a high voltage generation circuit that generates a high voltage using the pulse signal from this pulse generation circuit, and a sounding body driven by the voltage obtained from this high voltage generation circuit. In the alarm device, a plurality of pulse signal transfer lines each having at least one transmission gate constituted by a MOS transistor are provided between the pulse signal generation circuit and the high voltage generation circuit, and The resistance value of the on-resistance of the transmission gate in the pulse signal transfer line is set to be different, and the sound pressure of the sounding body can be varied by switching and selecting the pulse signal transfer line. alarm device.