Electronic Circuits and Diagram-Electronics Projects and Design

The op-amp triangular-wave generator is another example of a relaxation oscillator. We know that the integrator output waveform will be triangular if the input to it is a square-wave. It means that a triangular-wave generator can be formed by simply cascading an integrator and a square-wave generator, as illustrated in figure. This circuit needs a dual op-amp, two capacitors, and at least five resistors. The rectangular-wave output of the square-wave generator drives the integrator which produces a triangular output waveform. The rectangular-wave swings between +Vsat and -Vsat with a time period determined from equation. The triangular-waveform has the same period…

How to make a Schmitt trigger or a Regenerative Comparator using 741 IC ? A Schmitt trigger circuit is a fast-operating voltage-level detector. When the input voltage arrives at the upper or lower trigger levels, the output changes rapidly. The circuit operates with almost any type of input waveform, and it gives a pulse-type output. The circuit of an op-amp Schmitt trigger circuit is shown in figure. The input voltage vin is applied to the inverting input terminal and the feedback voltage goes to the non-inverting terminal. This means the circuit uses positive voltage feedback instead of negative feedback, that…

How to make a Monostable Multi Vibrator using 741 IC ? As already explained , a monostable multivibrator (MMV) has one stable state and one quasi-stable state. The circuit remains in its stable state till an external triggering pulse causes a transition to the quasi-stable state. The circuit comes back to its stable state after a time period T. Thus it generates a single output pulse in response to an input pulse and is referred to as a one-shot or single shot. Monostable multivibrator circuit illustrated in figure  is obtained by modifying the astable multivibrator circuit  by connecting a diode…

How to make an Astable or Free running Multi vibrator using 741 Op-Amp ? The non-sinusoidal waveform generators are also called relaxation oscillators. The op-amp relaxation oscillator shown in figure is a square wave generator. In general, square waves are relatively easy to produce. Like the UJT relaxation oscillator, the circuit’s frequency of oscillation is dependent on the charge and discharge of a capacitor C through feedback resistor R,. The “heart” of the oscillator is an inverting op-amp comparator The compa­rator uses positive feedback that increases the gain of the amplifier. In a comparator circuit this offer two advantages. First, the high…

How to make a Zero Crossing Detector using  311 Op-Amp IC ? A zero-crossing detector using IC 311 (8 pin DIP unit) is illustrated in figure. The positive (above 0 V) going input signal drives the output transistor on, the output going low (- 10 V in this connection). The negative (below 0 V) go­ing input drives the output transistor off, the output going high (+ 10 V in this connection). The output is thus an indication of whether the input is above or below 0 V. When the input is any positive voltage (above 0 V), the output is…

How to make a Zero Crossing Detector using 741 IC ? Zero-crossing detector is an applied form of comparator. Either of the op-amp basic comparator circuits discussed can be employed as the zero-crossing detector provided the reference voltage Vref is made zero. Zero-crossing detector using inverting op-amp comparator is depicted in figure. The output voltage waveform shown in figure indicates when and in what direction an input signal vin crosses zero volt. In some applications the input signal may be low frequency one (i.e. input may be a slowly changing waveform). In such a case output voltage vOUT may not switch quickly from…

Most digital systems require some kind of a timing waveform, for instance, a source of trigger pulses is required for all clocked sequential systems. In digital systems, a rectangular waveform is most desirable (unlike analog systems where sinusoidal signals are often used). The generators of rectangular waveforms are referred to as multivibrators. Multivibrators are of three types viz astable (or free-running) multivibrators, monostable multivibrators (or one-shot) and bistable multivibrators (or flip-flops). All these multivibrators have already been discussed. Until a few years ago, multivibrators used to be designed using discrete devices, such as vacuum triodes, bipolar junction transistors (BJTs), field-effect…

MOS (Metal Oxide Semiconductor)-IC’s As already mentioned in previous blog posts, ICs based upon the active devices are of two types viz. bipolar ICs using bipolar active devices like BJT and unipolar ICs using unipolar active devices such as FET. MOS ICs based on MOSFET structure are widely used in many applications especially in the digital field. This is because of its following advantages over bipolar ICs. 1. Reduction in Size. The MOS IC typically occupies only 5% of the surface required by an expitaxial double-diffused transistor in a conventional IC. Also, a MOS resistor occupies less than 1% of the area of…

How to make an integrated transistor amplifier ? We are now in a position to illustrate how a complete tran­sistor amplifier circuit including bias resistors can be formed on a silicon wafer using the masking and photolithographic processes, described earlier. The difference now is that the masking pattern must be layed out to include the appropri­ate interconnections as well. Appearing in figures is the complete IC layout of the transistor amplifier circuit shown in figure. The five circuit elements—one capacitor, three resistors, and one transistor—and all the interconnections are produced by the same masking, etching, and diffusion process-. In an…

Types of IC Packages For the protection of ICs from external environment and to provide mechanical protection and terminals for electrical connections, various types of packages are used. Several standard packages in general use are shown in figure. The metal can type of container provides electromagnetic shielding for the IC chip which cannot be provided by plastic or ceramic packages. The plastic dual-in-line package is much cheaper than other types of packages and is widely employed for general industrial and consumer applications where high temperatures are not met with. Ceramic or metal contain­ers are used where ICs are subjected to…