Welcome to electrical and electronics engineering Q&A site...

Welcome to electrical and electronics engineering discussion website, Please login or register to continue.

Join our WhatsApp group

Subscribe To Our YouTube Channel

Draw and explain the working of Schmitt trigger.

Amazon Shopping

Please log in or register to answer this question.

1 Answer

0 votes

A Schmitt trigger converts an irregular shaped waveform into a square wave. It is a special type of comparator in which the output changes from one saturation level to another saturation level depending on differential input voltage.


Consider the circuit shown below to which an a.c. voltage is applied. The potential at B is positive and at point A is zero. The differential voltage is positive, so the output voltage is driven to + V sat. At this instant, the potential at B is: VB = R2/(R1 +R2)*(+Vsat.).This voltage is called upper trigger point (VUTP).When input becomes more positive than VUTP, the differential input is negative. Therefore the output is driven to – VSAT. Now the potential at B is: VB = R2/(R1 +R2)*(-Vsat.) This voltage is called lower trigger point (VLTP).The output remains at –Vsat until input voltage becomes more negative than VLTP.When input becomes more negative thanVLTP, the differential input is again positive. Therefore the output is driven to + VSAT. the circuit diagram and waveforms are as shown.image

Amazon Shopping

Welcome to Q&A site for electrical and electronics engineering discussion for diploma, B.E./B.Tech, M.E./M.Tech, & PhD study.
If you have a new question please ask in English.
If you want to help this community answer these questions.


Most popular tags

power motor dc circuit transformer voltage current used system phase factor resistance load synchronous energy ac induction generator electric series frequency capacitor use speed between electrical meter line type mosfet control transmission difference magnetic plant high single instrument bjt source advantages function diode machine unit winding torque amplifier define supply thyristor motors arduino field shunt maximum relay armature problem electricity time parallel on transformers types coil diagram state flow value material three starting and direction theorem method emf operating digital microprocessor test instruments efficiency ratio loss measure operation connected low applications wave effect single-phase working losses different network wattmeter temperature measuring constant signal controlled breaker device full compare drive wire resistivity logic materials machines inductance switch flux disadvantages converter transistor gain protection scr angle force core measurement number free principle rc generators law negative bridge friction open pole conductor conservation steam iron loop resistors hysteresis short computer circuits using lines secondary station battery rectifier inverter linear relays nuclear regulation reactance design analog work rotor electronics gate forces diesel damping rlc connection factors capacitors minimum insulation basic moving running systems air fault range direct main stability quality starter igbt eddy ideal ammeter rl 3-phase plants arc induced thermal error fuzzy biasing dielectric pressure balanced superposition errors rotation characteristics feedback measured electronic start alternator off back curve over solar three-phase tariff locomotive peak bias zener capacitance commutator surge rating universal potentiometer permanent mechanical copper self transducer capacity electrons memory adc excitation inductive transfer explain fuse pure harmonics application inductor internal pmmc average reaction welding resonance traction breakers designed electromagnetic si generation brushes density switching shaded rate impedance distribution methods star oscillator reluctance semiconductor simplification algebra 8085 boolean weston dynamometer insulating strength installation permeability definition fuel heating earth units neutral rms rated engineering conductors coefficient controller usually reverse excited analysis change body components