SU563709A1 - Monostable multivibrator - Google Patents

Description

one

The invention relates to pulse techics and can be used in time delay devices, in frequency pulse modulation devices and in electrical measuring equipment.

A one-shot is known, which contains an on-amplification amplifier, a time setting capacitor, a resistive divider, and a source of onion voltage 1. However, it has insufficient stability of the generated impu; 1s because it is determined by the stability of the saturation voltage of the opting-in amplifier, in addition, the duration of the generated impulses There is no impulse noise, since the transition of the one-shot to the initial state does not occur at a zero voltage level at the output of the resistive divider.

A one-shot is also known, which also contains an operational amplifier, a capacitor, and a resistive divider 2. But it requires that the trigger pulses be of relatively large magnitude.

The closest technical solution to the present invention is a single-shot containing an operational amplifier, a first capacitor and a resistive divider, one input of which is connected to a common P1, and the middle point is connected to the first plate of the second capacitor 3. However, this single-shot has insufficient stability and gap. cost and value.

2

The purpose of the invention is to increase the stability and noise immunity of a single vibrator. This is achieved by introducing a reference current source, first and second MOS transistors, and a parametric voltage regulator into the proposed single vibrator, with the output of the reference current source connected to the inverter input of the operational amplifier, with the first capacitor lining and the drain of the first MOS transistor, the source of which is the second lining of the first capacitor connected to the common bus, and the gate of the first MOS transistor is connected to the output ohm operational amplifier, the parametric stabilizer input, the output of which is connected to the second input of the resistive divider, li with the gate of the second L1DP transistor, whose drain is connected to the input terminal of the one-shot, and the source to the second plate of the second capacitor, the first plate of which is connected to the non-inverting input of the operating booster.

The drawing shows a nipcipial circuit of the proposed one-shot.

The single-oscillator contains an operational amplifier 1, a first capacitor 2, a resistor 1vny divider on resistors 3 and 4, a second capacitor 5, a source 6 of the reference current, MDP transformers 7, 8, and a parametric voltage regulator 9, and the source output

6 is connected to the drain of the MDP transistor 7, the inverted input of amplifier 1 and through a capacitor 2 to a common bus connected through series-connected resistors 3, 4 and a stabilizer 9 to the output of amplifier 1, a gate of the MOS transistor 7, the source of which is connected to a common ear, and a gate of the MDG1-tra "of the resistor 8, the drain of which is the input of the odiovibrator, and the source is connected through a capacitor 5 to the non-inverted input of the silytel 1 and the output of the resistive divider.

The single vibrator works as follows.

Suppose that in the initial state the output output of amplifier I is negative and equal. In this case, the MOS transistors 7 and 8 are in the open state, as a result, the inverting input of the amplifier 1 will have a zero potential, and the non-inverting JM will have a voltage f / i, which is determined from

If // - R. + R.

where R {and R2 are the matches of resistors 3 and 4.

With the arrival of the field: an output triggering pulse, the amplitude of which exceeds the value Ui, an avalanche-like process occurs, as a result of which a positive voltage equal to the saturation voltage U: is generated at the output of the operational amplifier 1. At the same time MIS-Traisieto | 51) 1

7 and 8 are closed, the time setting capacitor 2 begins to charge from source 6, the input part of the one-shot is cut off from the source of trigger pulses. At the inverting input of amplifier 1, a voltage is applied AND, which is determined from the expression

//

W about 1

RI + RI

where f / cT is the voltage at the output of the parametric stabilizer 9.

Incidence on capacitor 2 increases linearly but by law

Ur and s -,

where / o is the current from the reference current source;

t is the current time;

C is the capacitance of capacitor 2. When the voltage across capacitor 2 reaches the level t / 2, a reverse avalanche-like process occurs. As a result, the output of amplifier 1 is set to negative.

the voltage (/ MOS-transistors 7 and 8 open, the capacitor 2 is discharged through the open MOS transistor 7.

The duration of the generated imiuls 7, j is determined from the ratio

T -

 P -

/ and (1 t)

All the components of the right-hand side of this expression can have a good effect: their desired stability and temperature stability, due to which a high stability of the duration of the emulsions generated is achieved.

Interference that may be present at the input of a single birator does not affect ia duration of 7 °, since during the generation of the emulsion of the trigger signal of the trigger pulses it is disconnected from the input of the odiovibrator.

Claims (3)

1. The patent of Germany L 1762290, cl. H 03 K 3/289, 1972. 2. Ermolov. R.S. Pifron1L1 frequency meters. M., “Eiergne, 1973, p. 82 3. .BTopCKoe witness. (SSR Du 358768, class H 03 K 3/284, 1972. + f