JPS5821235Y2 - Tongue anti-multi vibrator - Google Patents

Description

[Detailed description of the invention] This invention relates to a monostable multi-bi-break, and is designed to be stable by reducing the number of external parts even when integrated circuits, and to simplify the circuit configuration. .

An embodiment of the monostable multi-bibreak according to the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 indicates a switching element such as an npn transistor, and a voltage higher than the threshold voltage of this transistor 1 as shown in FIG. 2A is applied to the base of the transistor 1 from the trigger pulse input terminal 2. A trigger pulse signal having a relatively small pulse width is supplied, and when this trigger pulse signal is supplied to the base, this transistor 1 is turned on.

The collector of this transistor 1 is connected to one end of a resistor 3, and the emitter of this transistor 1 is grounded.

Further, the other end of the resistor 3 is connected to one end of the resistor 4 and also to one end of the capacitor 5.

Further, the other end of the resistor 4 is connected to a power supply terminal 6 that supplies a positive voltage, and the other end of the capacitor 5 is grounded.

In this case, the capacitor 5 is externally connected, and the resistor 3 and this capacitor 5 constitute a time constant circuit, and the resistor 4 and this capacitor 5 constitute a time constant circuit, and the resistance value of the resistor 3 is changed to the resistance value of the resistor 4.
Select a value sufficiently smaller than the resistance value of .

That is, the time constant of the time constant circuit composed of resistor 3 and capacitor 5 is set to be sufficiently smaller than the time constant of the time constant circuit composed of resistor 4 and capacitor 5.

Further, the resistance value of the resistor 4 is selected depending on the required time constant, that is, the required pulse width.

On the other hand, the other end of resistor 3 is connected to an npn type transistor F, and the collector of this transistor 7 is connected to resistor 8.
It is connected to the base of an npn transistor 10 through a series circuit of a resistor 9 and a resistor 9, and is also connected to a power supply terminal 6 through a resistor 10.

The collector of transistor 10 is connected to power supply terminal 6, and the base of transistor 10 is grounded via resistor 12.

Further, the emitters of the transistors 7 and 10 are connected to each other, and this connection point is connected to a resistor 13 constituting a constant current circuit.
Ground through.

These transistors 7 and 10 constitute a Schmitt circuit 14, so that when transistor 7 is on, transistor 10 is off, and when transistor 7 is off, transistor 10 is on.

Further, a differential amplifier 17 is configured by the npn type transistor 15 and the npn type transistor 16, and the emitters of each of the transistors 15 and 16 are connected to each other, and this connection point is connected to one end of the resistor 18. .

One end of this resistor 18 is further connected to the cathode of a diode 19, the anode of this diode 19 is connected to one end of the capacitor 5, and the other end of the resistor 18 is grounded.

In this case, the resistor 18 and the capacitor 5 constitute a time constant circuit, and the resistance value of the resistor 18 is selected to be sufficiently smaller than the resistance value of the resistor 4.

That is, the time constant of the time constant circuit made up of resistor 18 and capacitor 5 is set to be sufficiently smaller than the time constant of the time constant circuit made up of resistor 4 and capacitor 5.

Furthermore, the collector of the transistor 16 is connected to the power supply terminal 6, and the base of this transistor 16 is connected to the resistor 8 and the resistor 9.
Connect to the midpoint of the connection.

The base of transistor 15 is connected to power supply terminal 6 through resistor 4, and the collector of transistor 15 is connected to power supply terminal 6 through resistor 20.

Further, the output terminal 21 of this monostable multi-by-break is led out from the collector of the transistor 15, for example.

Since one embodiment of the rod-stabilizing multivibrator according to the present invention is constructed as described above, a pulse signal with a relatively small pulse width as shown in FIG. 2A is supplied to the base of the transistor 1 from the trigger pulse input terminal 2. Then, the base voltage of this transistor 1 becomes higher than the threshold voltage, and this transistor 1 is turned on.

Therefore, the capacitor 5 is discharged through the series circuit of the resistor 3 and the transistor 1, and in this case, the capacitor 5 is discharged due to the time constant of the time constant circuit of the resistor 3 and the capacitor 5.
Since the capacitor 5 is discharged in a relatively short time, the voltage across the capacitor 5 falls as shown by the curve a in FIG. 2B.

At this time, the base voltage of the transistor 7 constituting the Schmitt circuit 14 also decreases, so this transistor 7 is turned off, and the voltage drop between the terminals of the resistor 11 decreases, so the base voltage of the transistor 10 increases and The voltage rises to point b in FIG. 2C, and this transistor 10 is turned on.

In this case, since the resistance value of the resistor 3 is selected to be sufficiently small as described above, the time constant of the time constant circuit of the resistor 3 and the capacitor 5 is approximately determined by the capacitance value of the external capacitor 5. Therefore, the rise of the base voltage of the transistor 10 is stabilized.

Further, since the capacitor 5 maintains a discharged state until the pulse signal shown in FIG. 2A supplied to the base of the transistor 1 changes from, for example, +1 volt to zero volt and this transistor 1 is turned off, The voltage across the terminal becomes as shown in the curve shown in FIG. 2B.

The duration of this curve is then determined by the pulse width of the pulse signal applied to the base of transistor 1.

Next, when the transistor 1 turns off, the capacitor 5 is charged by the current from the power supply terminal 6 via the resistor 4, and in this case, due to the time constant of the time constant circuit of the resistor 4 and the capacitor 5, the capacitor 5 is charged. Since the capacitor 5 is charged over a relatively long predetermined time, the voltage across the capacitor 5 rises as shown by the curve C in FIG. 2B.

At this time, the base voltage of transistor 7 also rises, so
This transistor 7 is turned on, and the voltage drop across the terminals of the resistor 11 increases, so that the base voltage of the transistor 10 decreases to point d in FIG. 2C, and this transistor 10 is turned off.

After this, the capacitor 5 is discharged through the series circuit of the diode 19 and the resistor 18, and in this case, due to the time constant of the time constant circuit of the capacitor 5 and the resistor 18, the capacitor 5 is discharged in a relatively short time. Therefore, the voltage across the capacitor 5 falls as shown by curve i in FIG. 2B.

However, the voltage difference f that occurs between the voltages across the capacitor 5 at this time is determined by the resistance ratio of the resistors forming the Schmitt circuit 14.

Furthermore, when the capacitor 5 is charged as shown by curve C in FIG.
A current flows through the collector of this transistor 15, and a voltage difference g is generated between both ends of the resistor 20 as shown in the second diagram. Since the voltage decreases as the voltage across the capacitor 5 decreases as shown by the curve i in FIG.

Therefore, when the capacitor 5 is charged as shown by the curve C in FIG. 2B, a differential pulse signal as shown in the second diagram can be obtained at the output terminal 21.

After this, the capacitor 5 remains charged, and the voltage across the capacitor 5 becomes as shown by the curve e in FIG. 2B.

Furthermore, a second terminal is connected to the base of the transistor 1 from the input terminal 2.
When a trigger pulse signal with a relatively small pulse width as shown in FIG.

As a result, a differential pulse signal as shown in the second diagram, for example, can be obtained at the output terminal 21.

As described above, the monostable multivibrator according to the present invention requires only the capacitor 5 as an external component even when integrated into an integrated circuit, and is therefore stable against temperature and variations.

Further, according to the present invention, a monostable multivibrator can be constructed using only the switching elements such as the transistor 1, the time constant circuit, the Schmitt circuit 14, etc., so the circuit construction is simple.

Furthermore, since it is not a saturation type but a current switching type, it has the advantage that it can be used up to high frequencies.

Further, in this example, the output terminal 21 is led out from the other end of the resistor 20 connected to the collector of the transistor 15, and a differential pulse signal as shown in the second diagram is obtained as an output signal at this output terminal 21. However, in addition to this, the output terminal 21 can also be led out from a predetermined location in order to obtain a desired output signal.

Further, in this example, the other end of the capacitor 5 is grounded, but even if the other end of the capacitor 5 is connected to the power supply terminal 6, the charging and discharging operations will only be reversed. It is easy to understand that there are effects similar to those described above.

Note that the present invention is not limited to the above-described embodiments, and various other configurations may be adopted without departing from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a connection diagram showing an embodiment of the monostable multi-bibreak of the present invention, and FIG. 2 is a diagram for explaining the present invention. 1.7, 10, 15 and 16 are transistors, 2 is a pulse input terminal, 3, 4, 8, 9°11.
12, 13, 18 and 20 are resistors, 5 is a capacitor, 6 is a power supply terminal, 14 is a Schmitt circuit, 17 is a differential amplifier, 19 is a diode, and 21 is an output terminal.

Claims (1)

[Scope of utility model registration request] A series circuit of a resistor and a switching element connected between power supply terminals, a capacitor connected in parallel with the switching element or the resistor, first and second transistors constituting a Schmitt circuit, and emitters of the same a third and a fourth transistor connected to each other, a connection point between the resistor and the switching element is connected to a base of the first and third transistor, respectively, and a connection between the resistor and the switching element; a diode is connected between the point and the connection point of the emitters of each of the third and fourth transistors, the bases of each of the second and fourth transistors are connected to each other, and the third and fourth transistors are connected to each other. An output signal is obtained from at least one collector of the transistor, and in the Schmitt circuit, a feedback circuit is provided between the collector of the first transistor and the base of the second transistor, and the switching element is activated by a trigger pulse. A monostable multivibrator, characterized in that the capacitor is charged or discharged in a controlled manner, and the third transistor is turned on during a period in which the first transistor of the Schmitt circuit shifts from off to on.