JPH0818406A - Pulse width control method for one-shot multivibrator - Google Patents

Abstract

PURPOSE:To provide the pulse width control method of a one-shot multivibrator capable of varying an output pulse width without changing the resistance value of a charging resistor. CONSTITUTION:The serial circuit of the charging resistor 2 and a charging capacitance 3 is connected to a main body circuit 1 and the connection point of the charging resistor 2 and the charging capacitance 3 is connected as a charging point P. A voltage Vcc is applied from a power supply terminal 4 to the main body circuit 1. By supplying trigger pulses PTR to an input terminal 5, the output pulses POUT of a pulse width Tw are obtained in an output terminal 6. By applying a control voltage Vcw different from the voltage Vcc to the other end (the opposite side of the charging point P) of the charging resistor 2 and varying the voltage Vcw, the pulse width Tw of the output pulses POUT is varied. The pulse width Tw of the output pulses POUT is varied by varying the control voltage Vcw applied to the charging resistor 2, the pulse width Tw is not varied by varying the resistance value R of the charging resistor 2 and the pulse width Tw is accurately varied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the pulse width of a one-shot multivibrator.

[0002]

2. Description of the Related Art FIG. 9 shows the structure of a conventional one-shot multivibrator. Reference numeral 1 is a main circuit of the multivibrator. A series circuit of a charging resistor 2 and a charging capacitor 3 is connected to the main circuit 1 and the charging resistor 2
And the connection point of the charging capacity 3 is connected as the charging point P. A voltage Vcc is applied to the body circuit 1 from the power supply terminal 4. The other end of the above-mentioned charging resistor 2 (one end has the charging capacity 3
Voltage Vcc is also applied from the terminal 4.

Further, an input terminal 5 to which a trigger pulse PTR is supplied is derived from the main body circuit 1 and an output terminal 6 from which an output pulse TOUT is obtained is derived. in this case,
When the trigger pulse PTR is supplied to the input terminal 5 as shown in FIG. 10A, the output terminal 6 obtains the output pulse POUT having the pulse width Tw from the falling time t0 of the trigger pulse PTR as shown in FIG. . Here, the pulse width Tw
Is determined by a function of the type of IC forming the main body circuit 1, the value R of the charging resistor 2 and the value C of the charging capacity 3, and (1)
It can be expressed as a function of R and C like a formula.

Tw = F (R, C) (1)

[0005]

The pulse width Tw of the output pulse TOUT is generally changed by changing the resistance value R of the charging resistor 2. Further, the dynamic variation of the pulse width Tw of the output pulse TOUT is performed only by configuring the charging resistor 2 with an active element such as a transistor and dynamically changing the resistance value R thereof. In this way, the pulse width Tw of the output pulse TOUT is set to the resistance value R of the charging resistor 2.
However, according to the method of varying the output pulse width Tw, it is very difficult to accurately control the output pulse width Tw because it is necessary to accurately change the resistance value R of the charging resistor 2.

Therefore, the present invention provides a pulse width control method for a one-shot multivibrator which can vary the output pulse width with high precision.

[0007]

A pulse width control method for a one-shot multivibrator according to the invention of claim 1 is
One having one or more charging resistors connected at one end to a charging capacitor and varying the output pulse width by varying part or all of the applied voltage applied to the other end of the one or more charging resistors Is.

A pulse width control method for a one-shot multivibrator according to a second aspect of the present invention is the one according to the first aspect, wherein the applied voltage is dynamically varied to dynamically vary the output pulse width.

According to a third aspect of the present invention, there is provided a pulse width control method for a one-shot multivibrator according to the first or second aspect of the present invention, wherein the applied voltage applied to one or more charging resistors is a buffer amplifier or a D / D converter. It is supplied through the A converter.

A pulse width control method for a one-shot multivibrator according to a fourth aspect of the present invention is the one according to the first aspect, wherein one or more of which one end is connected to a connection point between the charging capacitor and one or more charging resistors. Is provided, the output pulse width is dynamically varied by dynamically varying part or all of the applied voltage applied to the other end of one or more capacitors.

A pulse width control method for a one-shot multivibrator according to a fifth aspect of the present invention is the method according to the fourth aspect, wherein the applied voltage applied to one or more capacitors is passed through a buffer amplifier or a D / A converter. To supply.

[0012]

According to the invention of claim 1, the output pulse width can be varied by varying a part or all of the applied voltage applied to the other end of the one or more charging resistors. Instead of changing the value to change the output pulse width, it is possible to change the output pulse width with high accuracy.

According to the second aspect of the present invention, the output pulse width can be dynamically and accurately varied by dynamically varying a part or all of the applied voltage applied to the other end of the one or more charging resistors. Is possible.

According to the third aspect of the present invention, the applied voltage applied to one or more charging resistors is changed to a buffer amplifier or a D / A.
Since it is supplied through the converter, fluctuations in output pulse width due to disturbance noise, jitter, etc. can be prevented even if the supply line of the applied voltage is lengthened, and the output pulse width can be easily changed by remote control.

In the invention of claim 4, the output pulse width can be dynamically and accurately varied by dynamically varying part or all of the applied voltage applied to the other end of the one or more capacitors. It will be possible.

According to the fifth aspect of the present invention, the applied voltage applied to one or more capacitors is supplied through the buffer amplifier or the D / A converter, and even if the supply line for the applied voltage is lengthened, the disturbance is disturbed. Fluctuation of output pulse width due to noise,
Jitter etc. can be prevented, and the output pulse width can be easily changed by remote control.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first embodiment of the present invention will be described below with reference to FIG.
An example will be described. In FIG. 1, parts corresponding to those in FIG. 9 are designated by the same reference numerals, and detailed description thereof will be omitted.

In this example, the other end of the charging resistor 2 (on the side opposite to the charging point P) is connected to a terminal 7, and this terminal 7 has a voltage Vcc (fixed voltage) supplied to the main circuit 1. Different control voltages Vcw are supplied. The present example is configured as described above, and the others are configured similarly to the example of FIG.

In this example, by varying the voltage Vcw supplied to the terminal 7, the pulse width Tw of the output pulse POUT can be varied. That is, in this example, the pulse width Tw is the value R of the resistor 2 and the value C of the charge capacity 3.
And the control voltage Vcw as a function, and can be expressed as a function of R, C, and Vcw as in Expression (2).

Tw = F (R, C, Vcw) (2) Note that FIG. 2 shows the SN74LS1 as the IC of the main body circuit 1.
23, Vcc = 5V, R = 1kΩ, C = 0.00
The relationship between the control voltage Vcw and the pulse width Tw when 1 μF is shown. In this case, when Vcw is varied from 3V to 7V, Tw can be varied from 985ns to 315ns.

As described above, in this embodiment, the pulse width Tw of the output pulse POUT is changed by changing the control voltage Vcw applied to the other end of the charging resistor 2, and the resistance value R of the charging resistor 2 is changed. Does not change the pulse width Tw, but the pulse width Tw can be changed accurately.

Next, a second embodiment of the present invention will be described with reference to FIG. 3, parts corresponding to those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

In this example, a plurality of charging resistors 2 ₁ ,
2 _2, ..., one end of the 2 _n are connected to the charging point P are commonly connected, the plurality of charging resistor 2 _{1, 2} 2, ..., 2 _n
The other ends of are connected to terminals 7 ₁ , 7 ₂ , ..., 7 _n , respectively. Then, these terminals 7 ₁ , 7 ₂ , ..., 7 _n have control voltages Vcw ₁ , Vcw ₂ , ..., Vcw _n different from the voltage Vcc (fixed voltage) supplied to the main body circuit 1, respectively.
Is supplied. The present example is configured as described above, and the others are configured similarly to the example of FIG.

In this example, the terminals 7 ₁ , 7 ₂ , ...,
Control voltage Vcw ₁ supplied to _{7 n, Vcw 2, ···,} Vcw n
Output pulse POU by changing part or all of
The pulse width Tw of T can be changed. That is, in this example, the pulse width Tw is equal to the resistances 2 ₁ , 2 ₂ , ...
..., value of _{2 n R 1, R 2,} ···, R n, the value C and a control voltage Vcw _1, Vcw ₂ charge capacity 3, ... are determined as a function of Vcw _n, (3) As in the formula, R ₁ , R ₂ , ...,
It can be expressed as a function of R _n , C, Vcw ₁ , Vcw ₂ , ..., Vcw _n .

Tw = F (R ₁ , R ₂ , ..., R _n , C, Vcw ₁ , Vcw ₂ , ..., Vcw _n ) (3) Note that FIG. In the case where the charging resistors R ₁ and R ₂ are connected, SN74LS123 is used as the IC of the main body circuit 1.
, Vcc = 5V, C = 0.001μF, R ₁ = 1k
It shows the relationship between the control voltage Vcw ₂ and the pulse width Tw when Ω, R ₂ = 10 kΩ and Vcw ₁ = 5V. In this case, when Vcw ₂ is varied from 3V to 7V, Tw is 437
It can be varied from ns to 397 ns.

As described above, also in this example, the control voltage Vc applied to the other ends of the charging resistors 2 ₁ , 2 ₂ , ..., 2 _n.
The pulse width Tw of the output pulse POUT is varied by varying part or all of w ₁ , Vcw ₂ , ..., Vcw _n , and charging resistors 2 ₁ , 2 ₂ , ..., 2 _n Resistance value R ₁ ,
The pulse width Tw is not changed by changing R ₂ , ..., R _n , but the pulse width Tw can be changed accurately as in the example of FIG.

Next, a third embodiment of the present invention will be described with reference to FIG. 5, parts corresponding to those in FIG. 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

In this example, the terminals 7 ₁ , 7 ₂ , ...,
Control voltage Vcw displayed as a function of time at 7 _n
1 (t), Vcw ₂ (t), ..., Vcw _n (t) are supplied. The present example is configured as described above, and the others are configured similarly to the example of FIG.

In this example, the terminal 7₁, 7₂・ ・ ・ ・ ・ ・
7_nControl voltage Vcw supplied to₁(T), Vcw₂(T),
..., Vcw_nChange part or all of (t)
And the pulse width Tw (t) of the output pulse POUT can be changed.
Can be made. That is, in this example, the pulse width
Tw (t) is resistance 2₁, 2₂・ ・ ・ ・ ・ ・ 2_nValue of R₁, R
₂・ ・ ・ ・ ・ ・ R_n, Value C of charge capacity 3 and control voltage Vcw
₁(T), Vcw₂(T), ..., Vcw_nIn the function of (t)
Determined and R as in equation (4)₁, R₂・ ・ ・ ・ ・ ・ R_n,
C, Vcw₁(T), Vcw₂(T), ..., Vcw_n(T)
Can be expressed as a function of.

Tw (t) = F (R₁, R₂・ ・ ・ ・ ・ ・ R_n, C, Vcw₁(T), Vcw₂(T), ..., Vcw_n(T)) (4) In this way, in this example, the pulse of the output pulse POUT is
The width can be obtained as a function of time Tw (t) and the control
Voltage Vcw₁(T), Vcw₂(T), ..., Vcw _n(T)
By dynamically changing part or all of the
The loose width Tw (t) can be changed dynamically.
It In this case, charging resistance 2₁, 2₂・ ・ ・ ・ ・ ・ 2_nResistance
Value R₁, R₂・ ・ ・ ・ ・ ・ R_nPulse width Tw
It does not dynamically change (t), but the pulse width
It is possible to dynamically change Tw (t) accurately.
Wear.

Next, a fourth embodiment of the present invention will be described with reference to FIG. 6, parts corresponding to those in FIG. 5 are designated by the same reference numerals, and detailed description thereof will be omitted.

In this example, one ends of a plurality of capacitors (capacitances) 8 ₁ , 8 ₂ , ..., 8 _n are commonly connected to a charging point P, and the plurality of capacitors 8 ₁ , 8 ₂ are connected. ，
The other ends of 8 _n are terminals 9 ₁ , 9 ₂ , ...
9 _n . Then, these terminals 9 ₁ , 9 ₂ , ...
.., 9 _n , the control voltage Vm ₁ displayed as a function of time
(T), Vm ₂ (t), ..., Vm _n (t) are supplied. The present example is configured as described above, and the others are configured similarly to the example of FIG.

In this example, the voltages Vm ₁ (t), Vm
By varying a part or all of ₂ (t), ..., Vm _n (t), the pulse width Tw (t) of the output pulse POUT
Can be changed. That is, in this example,
The pulse width Tw (t) is the value R ₁ , R ₂ , ..., R _n of the resistors 2 ₁ , 2 ₂ , ..., 2 _n , the value C of the charge capacity 3 and the control voltage Vcw ₁ (t). , Vcw ₂ (t), ..., Vcw
_n (t), Vm ₁ (t), Vm ₂ (t), ..., Vm
It is determined by a function of _n (t) and can be expressed as in equation (5).

Tw (t) = F (R₁, R₂, ..., R_n, C, Vcw₁(T), Vcw₂(T), ..., Vcw_n(T), Vm₁(T), Vm₂(T), ..., Vm_n(T)) (5) Thus, in this example, the control voltage Vm₁(T), V
m₂(T), ..., Vm _nDie part or all of (t)
Even if the output is changed to be namic, the output is the same as in the example of FIG.
Allows pulse width Tw (t) of pulse POUT dynamically
It can change.

Next, a fifth embodiment of the present invention will be described with reference to FIG. 7, parts corresponding to those in FIG. 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

In this example, a plurality of charging resistors 2 ₁ , 2 ₂ ,
, 2 _{n to} the other end (on the side opposite to the charging point P) from terminals 10 ₁ , 10 ₂ , ..., 10 _n , respectively.
Control voltages Vi ₁ , V via 1 ₁ , 11 ₂ , ..., 11 _n
i _2, ···, it is Vi _n is applied. The present example is configured as described above, and the others are configured similarly to the example of FIG.

As in this example, a plurality of charging resistors 2 ₁ , 2 ₂ ,
..., 2 _n to buffer amplifiers 11 ₁ , 11 ₂ , ...
·, 11 a control voltage via the _n that is to be applied, even by increasing the supply line of the voltage applied to the fluctuation of the pulse width Tw of the output pulse POUT by external noise, it can be prevented such as jitter, remote control The pulse width Tw can be easily changed by.

Next, a sixth embodiment of the present invention will be described with reference to FIG. 8, parts corresponding to those in FIG. 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

In this example, a plurality of charging resistors 2 ₁ , 2 ₂ ,
..., the the 2 _n other end (opposite to the charging point P), respectively terminals 12 _1, 12 _2, ..., the digital data [D11~D1m] supplied to 12 _n, [D21~ D2m] 、 ・ ・ ・ 、
[Dn1 to Dnm] are D / A converters 13 ₁ , 13 ₂ , ...
At 13 _n, it is converted into an analog control voltage and applied.
The present example is configured as described above, and the others are configured similarly to the example of FIG.

As in this example, a plurality of charging resistors 2 ₁ , 2 ₂ ,
..., 2 _n to D / A converters 13 ₁ , 13 ₂ , ...
..., 13 a control voltage via the _n that is to be applied, as in the example of FIG. 7, even by increasing the supply line of the voltage applied to the output pulse POUT by external noise pulse width Tw
Fluctuation, jitter, etc. can be prevented, and the pulse width Tw can be easily changed by remote control.

It should be noted that applying a control voltage through a buffer amplifier or a D / A converter as in the examples of FIGS. 7 and 8 and applying a control voltage that dynamically varies as in the example of FIG. In this case, or when the control voltage is applied to the capacitors 8 ₁ to 8 _n as in the example of FIG. 6, the same effect can be obtained.

[0042]

According to the first aspect of the present invention, the output pulse width can be changed by changing a part or all of the applied voltage applied to the other end of one or more charging resistors. Instead of changing the resistance value of the resistor to change the output pulse width, the output pulse width can be changed with high accuracy.

According to the second aspect of the present invention, the output pulse width is dynamically and accurately varied by dynamically varying part or all of the applied voltage applied to the other ends of the one or more charging resistors. be able to.

According to the third aspect of the present invention, the applied voltage is applied to one or more charging resistors via the buffer amplifier or the D / A converter. Even if the supply line for the applied voltage is lengthened, disturbance noise is generated. It is possible to prevent fluctuations in output pulse width, jitter, etc. due to, and to easily change the output pulse width by remote control.

According to the fourth aspect of the invention, the output pulse width can be dynamically and accurately varied by dynamically varying part or all of the applied voltage applied to the other end of the one or more capacitors. it can.

According to the fifth aspect of the present invention, the applied voltage is applied to one or more capacitors via the buffer amplifier or the D / A converter, and even if the supply line of the applied voltage is lengthened, it is caused by disturbance noise. It is possible to prevent fluctuations in output pulse width, jitter, etc., and easily change the output pulse width by remote control.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a control voltage and a pulse width in the first embodiment.

FIG. 3 is a configuration diagram showing a second embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between a control voltage and a pulse width in the second embodiment.

FIG. 5 is a configuration diagram showing a third embodiment of the present invention.

FIG. 6 is a configuration diagram showing a fourth embodiment of the present invention.

FIG. 7 is a configuration diagram showing a fifth embodiment of the present invention.

FIG. 8 is a configuration diagram showing a sixth embodiment of the present invention.

FIG. 9 is a configuration diagram showing a conventional one-shot multivibrator.

FIG. 10 is a diagram showing a relationship between a trigger pulse and an output pulse.

[Explanation of symbols]

1 Multivibrator main circuit 2, 2 _{1 to} 2 _n Charging resistor 3 Charging capacity 4 Power supply terminal 5 Input terminal 6 Output terminal, 7, 7 _{1 to} 7 _n , 9 _{1 to} 9 _n , 10 ₁ to 10 _n , 12 ₁ ~ 12 _n
Terminal 8 ₁ to 8 _n capacitors (capacitance) 11 ₁ to 11 _n buffer amplifiers 13 ₁ ~13 _n D / A converter

Claims (5)

[Claims] 1. An output is provided by having one or more charging resistors, one end of which is connected to a charging capacitor, and varying a part or all of an applied voltage applied to the other end of the one or more charging resistors. A pulse width control method for a one-shot multivibrator, wherein the pulse width is variable. 2. The pulse width control method for a one-shot multivibrator according to claim 1, wherein the applied voltage is dynamically varied to dynamically vary the output pulse width. 3. The one-shot multivibrator according to claim 1, wherein the applied voltage applied to the one or more charging resistors is supplied via a buffer amplifier or a D / A converter. Pulse width control method. 4. One or more capacitors, one end of which is connected to the connection point of the charging capacitor and one or more charging resistors, are provided, and one of the applied voltage applied to the other end of the one or more capacitors. 2. The pulse width control method for a one-shot multivibrator according to claim 1, wherein the output pulse width is dynamically changed by dynamically changing part or all of the parts. 5. The pulse width control method for a one-shot multivibrator according to claim 4, wherein the applied voltage applied to the one or more capacitors is supplied via a buffer amplifier or a D / A converter. .