JPS582489B2 - Denatsuniyorparushababa Moshikuha Shuukikahengatapalushatsei Cairo - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pulse generation circuit that varies pulse width or period depending on voltage.

An object of the present invention is to provide a pulse generation circuit that can vary the period or pulse width depending on the voltage.

Another object of the present invention is that when the voltage is high, the pulse width is short;
On the other hand, when the voltage is low, the pulse width or period is long, and the rate of change is approximated by the inverse proportion of the square of the power supply voltage.The pulse width or period varies depending on the application. It is an object of the present invention to provide a pulse generation circuit that can adjust the amount of change in .

Still another object of the present invention is to provide control that actively changes the pulse width in order to supply constant energy in response to fluctuations in the power supply, especially in the control of electronic devices using dry batteries as the drive source, where the power supply voltage fluctuates. The object of the present invention is to provide a pulse generation circuit that obtains an optimal signal for the system.

Still another object of the present invention is to provide a pulse generation circuit that can change the pulse width depending on the temperature of the environmental conditions and is optimal as a signal source for constant temperature driving of electronic components and electronic equipment.

FIG. 1 is a circuit diagram of an embodiment of a pulse generating circuit according to the present invention.

It is characterized by incorporating a varistor into the resistor part that determines the time constant of the commonly used unstable multi-bye break.

A typical multi-bye break that does not use a varistor is
In most cases, the oscillation period changes irregularly with respect to the power supply voltage, or the period hardly changes even if the voltage changes.References 1 and 2 are oscillation transistors in the oscillation circuit, and are connected to capacitors. 4, 6, the resistor section 3 (inside the dotted line), and the resistor element 5 determine the time constant and the period T.

The resistance section 3 includes a varistor 7 and a resistance element 8.

A varistor has characteristics as shown in FIG. 2 in terms of the relationship between applied voltage x and flowing current i.

In other words, as the height of the electrician increases, the resistance value decreases and the current increases rapidly.

The present invention actively utilizes this characteristic.

FIG. 3 shows how the output waveform of the oscillation circuit changes with changes in the power supply voltage v1 (assuming that the power supply voltage of the pulse generating circuit in FIG. 1 is v1).

α is the second characteristic diagram of the varistor when the power supply voltage v1 is high.
It can be seen from the figure that the resistance value has become smaller.

Therefore, the time constant τ1=C4R3 is also small and the period is short.

As the power supply voltage v1 decreases, the resistance value of the varistor 7 also increases and the time constant τ1=C4R3 increases, so in the circuit shown in FIG. 1, the high level time of the output waveform rapidly increases and the period T becomes longer.

b and c show the states of the output waveforms showing the situation.

This relationship is shown in a graph as shown in FIG.

The y-axis shows the power supply voltage v1, and the X-axis shows the period T.

d and e show characteristic curves of circuits with different resistance section configurations.

Depending on the characteristics of the varistor 1 and how it is combined with the resistive element, it is possible to create various characteristic curves in addition to d and e depending on the application.

Further, if it is desired to change the cycle significantly, a varistor may be used for the resistor 5 as well.

Figure 5 shows an example of the configuration of the resistance section 3, where K is an example where only a varistor is used, l is an example where a varistor and a resistance element are connected in series, and m is an example where a varistor and a resistance element are connected in parallel. In the example, n indicates an example in which a resistance element is connected in series to a parallel circuit of a varistor and a resistance element.

FIG. 6 shows another embodiment of the present invention, in which the present invention is applied to an oscillation circuit of an IC such as a C-MOS-IC that is allowed to vary the power supply voltage.

Time constant τ2 of capacitor 11 and resistor section 12=C11×R
12 determines the frequency.

FIG. 1 shows yet another embodiment of the invention, which is a monostable multi-bibreak.

21 is a capacitor, 22 is a varistor, 23 is a thermistor, and 24 is a resistance section formed by the varistor 22 and the thermistor 23.

Due to the resistance section 24 and capacitor 21, the time constant τ3=C
21·R24 is determined, and the pulse width is determined.

FIG. 8 shows input and output waveforms of the monostable multi-bi break shown in FIG.

0 provides a trigger on the input waveform of the multivibrator.

P, Q, and R indicate the state of the output waveform, and as the power supply voltage V3 decreases, the pulse width increases and changes from WP to WQ to WR.

23 in FIG. 7 is a thermistor. This is the power supply voltage V3
The idea is to not only change the pulse width of the output waveform depending on changes in the output waveform, but also change the pulse width depending on temperature, which is one of the environmental conditions.

In this case, if a negative characteristic thermistor is used, the pulse width will be short when the temperature is high, and conversely, the pulse width will be long when the temperature is low.

In the embodiment of FIG. 1, the configuration example of the resistance section 24 is as follows:
Although the thermistor 2 and the thermistor 23 are connected in parallel, various configuration methods can be considered depending on the purpose, such as adding a fixed resistance.

FIG. 9 is an example of an application using the monostable multivib break shown in FIG.

Reference numeral 31 denotes an oscillator that oscillates at a relatively stable period and is not affected by the power supply voltage V4.

32 is the monostable and multi-by-break (
The oscillator 31 generates a predetermined pulse by triggering the oscillator 31 (hereinafter M.M).

33 is a signal transmission resistor that sends a signal to the 7 driving transistor 34.

The driving transistor 34 is turned on when the MM32 is at a high level, and conducts current to the load 35.

A current is supplied to the load 35 with a short energization width when the power supply voltage is high, and with a long energization width when the power supply voltage V4 is low.

When the load 35 has a simple resistance value, the energy E supplied in one cycle is expressed by the following equation.

If the resistance value of the resistor is R35, becomes.

Next, if E is constant, then V■×W=E・R35=constant (Formula-2). If the MM 32 is configured in combination with the above, the load 35 can maintain an isoenergetic state, that is, a constant temperature and constant power, even when the power supply fluctuates.

Experiments have shown that depending on the construction method of k in FIG. 5, that is, the varistor alone, the pulse width change matches Equation (2) depending on the type.

The thermistor 23 has a characteristic that its resistance value decreases as the temperature rises, so if it is inserted as shown in Figure 1, the pulse width will be short when the temperature is high, and long when the temperature is low. Become.

If this characteristic is applied to the circuit shown in FIG. 7, it is possible to compensate for environmental temperature changes.

Some capacitors have capacitances that change depending on the temperature, and by using a capacitor whose capacitance decreases as the temperature increases, it is possible to create a behavior similar to the thermistor described above by using a capacitor 21 in Figure 1 whose capacitance decreases as the temperature rises. .

This type of temperature control is most effective,
The thermal head of the thermal printer is raised.

Surfle printers are one type of equipment for which the above-mentioned constant temperature control is particularly effective, since the print quality varies significantly depending on the temperature of the thermal head.

Further, when a lamp is used as the resistor 35 and the lamp is turned on, it is possible to emit light at a constant brightness despite voltage fluctuations by making the cycle of the oscillator 31 fast enough to prevent the lamp from blinking.

In addition, by using pulse width control using a power supply as a drive signal for power electronic devices such as step motors and Platzers, it is possible to suppress heat generation to a constant level despite voltage fluctuations, which is effective in preventing thermal damage to devices. be.

There are two types of varistors used in the present invention, unidirectional and bidirectional, and the materials include silicon, silicon carbide, zinc oxide, etc., and any of them can be used.

As described in detail above, the pulse width or period variable type pulse generation circuit according to the present invention can be widely applied to the field of electronic equipment.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of a pulse generation circuit according to the present invention.
3 is a resistance section that determines the time constant, 7 is a varistor, and 8 is a resistance element. Figure 2 shows the applied voltage and current characteristic curves of the varistor. FIG. 3 shows the output waveform of the pulse generation circuit shown in FIG. 1. FIG. 4 is a characteristic curve of the output waveform due to the difference in power supply voltage of the pulse generation circuit of FIG. 1. FIG. 5 shows an example of the configuration of the resistance section 3. FIG. 6 shows an example of use in a C MOSIC in another embodiment of the present invention. FIG. 7 shows still another embodiment of the present invention, in which a varistor and a thermistor are incorporated into a monostable multi-vibration brake. 24 is a resistor related to a time constant, 22 is a varistor, and 23 is a thermistor. FIG. 8 shows input and output waveforms of the monostable multi-by-break of FIG. 7. FIG. 9 is an example of an application circuit to which the present invention is applied, in which 32 is a monostable multi-vibration brake using the varistor of the present invention;
4 is a schematic diagram showing each driving transistor.

Claims (1)

[Claims] 1. It has at least one set of charging means formed by connecting a resistor means and a capacitor means in series, one end of the resistor is connected to one end of a power source, and the capacitor is charged through the resistor, In a pulse generating circuit which is based on discharging the capacitor at a predetermined time after charging, the resistor means is approximated to the inverse proportion of the square of the power supply voltage by using a resistor group including at least a varistor. A pulse generation circuit characterized in that it generates a pulse width or period that corresponds to the width or period of the pulse.