Basic Electronics

Definition: Phase-locked loops are the circuits used to maintain synchronization between input and output frequency of oscillator circuits by comparing the difference in phase of the two signals. With the evolution of IC, it has emerged as the basic building block of electronic circuits. Phase-locked loops are abbreviated as PLL and are basically a feedback circuit comprising of a phase detector (or comparator), a low pass filter and voltage-controlled oscillator along with an … [Read more...] about Phase-Locked Loops (PLL)

Definition: Beat Frequency Oscillator or BFO is an oscillator that produces a sinusoidal signal of the variable audio frequency range. It provides such a frequency that can be varied over a very large range. BFO was invented in 1901 by Reginald Fessenden. It is among the most common type of oscillator that can generate a signal of variable frequency at its output. Block Diagram and Working of Beat Frequency Oscillator The figure below represents the block diagram of a BFO:Here as we can … [Read more...] about Beat Frequency Oscillator (BFO)

Definition: Phase shift oscillators are the oscillators that generate a stable sinusoidal signal at the output. Basically, the circuit has, an amplifier unit like transistor or op-amp along with a feedback network comprising of resistors and capacitors. Thus, is also known as RC phase shift oscillator. The RC network is present in the feedback path is connected in ladder fashion thus also known as ladder RC phase shift oscillator. We know for an RC circuit; the output voltage leads the input … [Read more...] about Phase Shift Oscillator

Definition: An op-amp detector that has the ability to detect the change from positive to negative or negative to a positive level of a sinusoidal waveform is known as a zero crossing detector. More specifically, we can say that it detects the zero crossing of the applied ac signal. It is basically a voltage comparator whose output changes when the input signal crosses the zero of the reference voltage level. Thus it is named so. It is also known to be a square wave generator as the … [Read more...] about Zero Crossing Detector

Definition: A relaxation oscillator is basically a non-linear oscillator that has the ability to generate a non-sinusoidal periodic waveform at its output. Such as triangular wave, square wave etc. These are also known as non-sinusoidal waveform generators. A relaxation oscillator operates in such a way that it generates oscillations by charging the capacitor and quickly discharging it after attaining a pre-determined threshold voltage. The figure below will help you to understand the … [Read more...] about Relaxation Oscillator

Definition: A special type of amplifier that is used to amplify signals of extremely low-level is known as Instrumentation Amplifier. It is basically a differential amplifier, that performs amplification of difference of input signal. It has high CMMR, offers high input impedance and consumes less power. CMMR stands for common mode rejection ratio, it is the ability to reject unwanted signals. It is also known as data amplifier. Nowadays, it has become an elemental part of modern … [Read more...] about Instrumentation Amplifier

Definition: A bandpass filter (BPF) is an electronic circuit that passes a certain band of frequency without attenuation. The particular band of frequency passes by the filter is known as passband. The important parameters that have to be considered in a BPF are the low and high cut-off frequency, centre frequency along with bandwidth and selectivity. Bandpass filters are basically of two types: Active BPF and Passive BPF. An active bandpass filter requires an external power supply and … [Read more...] about Bandpass Filter

Definition: Photoresistor is a type of device whose resistance changes with respect to the intensity of the incident radiation. It has a tremendous ability to change its resistance in exposure to light. LDR is an acronym for Light Dependent Resistor. It is a non-linear device. The photoresistor is also termed as the light dependent resistor or photoconductor as it displays the property of photoconductivity. What photoconductivity basically is? It is the phenomenon which improves the … [Read more...] about Photoresistor – Light Dependent Resistor (LDR)

Definition: TRIAC is basically a 3 terminal ac switch that shows conduction in both the directions. These are triggered into conduction by low energy gate signal. TRIAC is a contraction of TRIode for Alternating Current. It is a bidirectional device that belongs to the thyristor family and is basically a diac with gate terminal used to control the turn-on conditions of the device. Let us have a look at the schematic symbol of a TRIAC: More specifically we can say in TRIAC, Tri denotes … [Read more...] about TRIAC

Definition: VCO is an acronym for Voltage Controlled Oscillator. It is a device that produces such an oscillating output signal whose frequency can be regulated or altered by the input dc voltage. In other words, we can say, VCO generates an output signal having an adjustable frequency range that is controlled by the dc input voltage. It is a type of oscillator in which the output frequency obtained is the function of the input signal. Usually, the frequency of an oscillator is … [Read more...] about Voltage Controlled Oscillator (V C O)