Picture Courtesy: GoogleAstable Multivibrator is a two stage R-C coupled amplifier with positive feedback from output of one amplifier to the input of other amplifier. It is a switching circuit which has no stable states as it always changes from one state to another. That’s why it got the name Astable Multivibrator. Astable Multivibrator is …
Darlington transistor is a back to back connection of two NPN or PNP Bipolar Junction Transistors(BJT). As shown in figure the Emitter of one transistor is connected to the base of other transistor. Darlington transistor was invented by Sidney Darlington in the year of 1953. A Darlington transistor configuration also known as “Darlington pair” or …
To identify value of resistance of a resistor colour coding is used. Because size of the resistor is very small so we cant print resistance value on the physical structure. Thus we use coloured rings, These coloured painted bands produce a system of identification generally known as a Resistors Colour Code. Generally there are four colour …
Operatinal amplifier Operatinal amplifier or OPAMP are basic element in an analogue circuit. Opamp is a linear device. When signal is applied to minus terminal of opamp then output is in opposite phase of input. Differential gain of opamp should be greater than common mode gain. Ideal value of common mode rejection ratio CMMR is …
Continue reading ‘Operational amplifier and Opto-electronic devices’ »
Feedback amplifier Feedback factor varies with frequency, so negative feedback may change to positive and vice versa. OPAMP comparator doesn’t have any feedback. In common emitter amplifier the unbypassed emitter resistance is current series feedback. Voltage negative feedback is used in emitter follower. De-sensitivity factor is defined as the factor with which the feedback desensitizes …