322 monostable multivibrator is cross-connected, when run under non-steady state condition between the oscillator Unicom, it will produce a continuous timing cycle, the same as

The schematic for a monostable multivibrator is shown in figure 3-11. Like the astable multivibrator, one transistor conducts and the other cuts off when the circuit is energized.

The logic diagram of the CD4538BC Dual Precision Monostable is shown in the following schematic diagram. This IC such a dual, precision monostable multivibrator with independent trigger and controls, according to the datasheet. This CD4538BC IC features wide supply voltage range, wide pulse-width range, low standby current, high noise immunity and more.

The ICM7216A or can be used as a minimum component complete Universal Counter. This circuit can use input frequencies up to 10 MHz at INPUT A and 2 MHz at INPUT B. If the signal at INPUT A has a very low duty cycle it may be necessary to use a 74121 monostable multivibrator or similar circuit,

The circuit is built around a 4001 quad two-input NOR gate, it provides switch selectable auto-advance times of 5, 10, 15, 20, 25 or 30 seconds through the remote-control socket of your projector. Ula and Ulb form an astable multivibrator, with its operating frequency dependent on the number of timing resistors switched into the circuit via S2. The frequency is about one cycle for every five seconds with a single timing resistor, one every ten seconds with two resistors, etc., providing six switched time intervals. The output of the astable at pin 4 of Ulb is fed to the input of a monostable multivibrator, consisting of the second pair of gates, Ulc and Uld. R7 and C3 are the timing components; they set the length of the (positive) output pulse of the monostable at a little more than half a second.

The application involves observing the light pulse emerging from a thick specimen after transillumination by a laser pulse. Pulses derived from the laser source are amplified using a Video Amplifier LM733. The reference level is set to 1 V in the comparator LM 710, to provide the necessary trigger pulses for the monostable multivibrator 74121. The laser pulses have a repetition frequency of 500 Hz and suitable values are as below: Rl = 33 k ohm, Cl = 22 pF R2 = 33 k ohm, C2 = 68 nF.

The 555 is used in a monostable multivibrator circuit that puts out a fixed timewidth pulse

This circuit converts frequency to voltage by taking the average dc value of the pulses from the 74121 monostable multivibrator. The one shot is triggered by the positive-going ac signal at the input of the 529 comparator. The amplifier acts as a dc filter, and also provides zeroing. The accuracy is 2% over a 5 decade range

This window comparator generates an output pulse for each event that occurs within a specified window. That is, each output pulse signifies an input voltage pulse or level change that exceeds VREFLOW. but not VREFHIGH· The monostable multivibrators, IC2A and IC2B, produce a 10-l"s pulse at their Q output in response to a rising edge at their A input. Comparator IC1B produces a rising edge when the input exceeds VREF Low and comparator IC2A produces a rising edge when the in])ut exceeds VREFHIGH.·

A single monostable multivibrator delays a pulse train by a variable amount; nonetheless, this amount can be no less than the minimum allowed pulse width fw· The exclusive-OR gate, IC1, generates a short pulse following every leading or falling edge of the input waveform. These pulses cause one-shot IC2 to produce a negative-going pulse with a duration equal to the desired time delay tp, which you set by adjusting potentiometer R.

You can obtain well over 360° of phase delay by cascading two monostable multivibrators. In a typical configuration, a single monostable multivibrator is used to introduce delay in a pulse train; the multivibrator triggers on each incoming pulse, provided it resets in time for the next pulse. Yet even when it resets in time, the single monostable multivibrator provides a maximum phase delay of less than 360°. However, with the cascaded-multivibrator approach, you can achieve 650° of phase delay by using an input-pulse spacing of 200 p.s for example, with the component values shown. Every input pulse will trigger the circuit while you adjust the phase delay throughout its available range.

The circuit can be used to tell whether or not an input signal is within a certain frequency range. The device consists of three !Cs, a dual monostable multivibrator, and two dual D-type flip-flops. The signal whose frequency is in question is fed to the clock input of one of the flip-flops. The Q output of that flipflop (IC1a) is cross coupled to its data input so that it acts like a divide-by-two counter. The trailing edge of the Q output is used to trigger the one shots formed by IC2.

Requiring only two ICs to monitor a train of positive pulses, this circuit produces a single positive output pulse for each input pulse whose duration is either too long or too short. You specify the minimum and maximum limits by adjusting the trimming potentiometers, R1 aod R2. You cao set the value of the acceptable pulse width from approximately 50 ns to 10 f-!S, for a 74123 monostable multivibrator. The leading edge of ao input pulse triggers one shots IClA and IClB as you cao see from the timing diagram.

The gate drive that phase controls the four parallel SCRs is accomplished with complementary MOS hex gate MC14572 and two bipolar transistors. This adjustable line-synchronized driver pennits SCR conduction from near zero to 180 degrees. A Schmitt trigger clocks a delay monostable multivibrator that is followed by a pulse-width monostable multivibrator. Line synchronization is achieved through the half-wave section of the secondary winding of the full-wave, center-tapped transformer.

If you need a wide-range, resistor-programmable monostable multivibrator, you can program tbe circuit for pulse widths from 1 JlS to 10s-107:1 range. A high-to-low transition at tbe input causes IC1"s output to switch low, thereby turning off Q1 and Q2. With tbe latter transistor turned off, IC3"s output increases and tbe output ofIC2 begins to ramp toward tbe negative supply level at a rate determined by the 0.01-JlF capacitor and tbe programming resistor.

This circuit operates by charging a small capacitor from a constant-current source when the pulse to be measured is present. Dual pnp transistor Q3 is the current source; its output current equals the LM329 reference voltage divided by the resistance of potentiometer Rl. When the input is high with no pulse present, Ql keeps the current source turned off. When the pulse begins and the input decreases, Ql turns off and the monostable multivibrator generates a short pulse.

The circuit converts frequency to voltage by taking the average de value of the pulses from the 7 4121 monostable multivibrator. The one shot is triggered by the positive-going ac signal at the input of the 529 comparator. The amplifier acts as a de filter, and also provides zeroing. This circuit will maintain an accuracy of2% over 5 decades of range.

Oscilloscope measurements of ground noise can be unreliable because noise can enter your circuit via the scope"s three-pronged power plug. You can avoid this problem by using the ground-noise tester shown. Powered by two 9-V batteries, the circuit dissipates power only while push-to-test switch Sl is depressed. Noise pulses that reach IC2A"s switching threshold of about 1.5 to 1.8 V create a logic transition that triggers the monostable multivibrator IC3, which stretches the pulse to produce a visible blink from LED Dl.

Comprising two low-power, CMOS chips, thepulse generator produces a precise pulse width in the 50 to 500 ns range. ICl is a dual monostable multivibrator (one shot) in which each positive trigger pulse initiates simultaneous positive output pulses at pins 6 and 10. In response, XOR gate IC2 produces a positive pulse whose duration is equal to the difference between the two input-pulse durations. Section 1 of the one shot generates an approximate 1-~ts reference pulse-shorter pulses are more susceptible to manufacturing variations caused by parasitic layout capacitance.

The 4047 is configured as a monostable multivibrator circuit or one shot that is set up to trigger on a negative-transition of the signal applied to its pin 6 input. The multivibrator"s on time is determined by the values of R1 and Cl. Although R1 is shown to be a 100-K unit, its value can be anything between 10 K and 1 MO. Capacitor C1 can be a nonpolarized capacitor with any practical value above 100 pF. By making R4"s value extremely high, the circuit can be used as a touch-triggered one-shot multivibrator.