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smruti
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If you are given a pure sinusoidal wave and a perfect DC is required from it. then what is the best way to get it? should we go for full bridge rectifiers? or any better way is there?
Are you , for your purposes, content to regard a full-wave rectified sinewave as "perfect DC"?smruti said:If you are given a pure sinusoidal wave and a perfect DC is required from it. then what is the best way to get it? should we go for full bridge rectifiers? or any better way is there?
Most high value capacitors are electrolytic. Electrolytic capacitors have a phenomena called effective equivalent series resistance (ESR) which is frequency dependent. The purpose of the small "bypass" capacitor is to cancel this effect. It is not needed if you pony up for an expensive ceramic capacitor as your main capacitor. Pairing a cheap electrolytic and a cheap small (perhaps mica?) capacitor is often the most economical choice for medium to large production runs.thankz said:a long time ago I learned that you should use slo diodes for ac rectification as fast diodes can introduce rf noise and need snubbers, as long as you use the right capacitance you ripple will be low, then you need an additional small value cap also to bypass because of internal resistance in the big cap at high freq, linear technology makes some better replacement 3 terminal regulators with better specs in every way than the lm317 they also come in negative, remember to use a 10uf cap after the regulator also
It seems this type of advice goes for many things in electronics. For example we use large electrolytics in parallel with small micas. This seems stupid to the untrained/unexperienced. There is no one component that covers from DC to GHz.thankz said:a long time ago I learned that you should use slo diodes for ac rectification as fast diodes can introduce rf noise and need snubbers, as long as you use the right capacitance you ripple will be low, then you need an additional small value cap also to bypass because of internal resistance in the big cap at high freq, linear technology makes some better replacement 3 terminal regulators with better specs in every way than the lm317 they also come in negative, remember to use a 10uf cap after the regulator also
A precision rectifier is a circuit that converts an alternating current (AC) signal into a direct current (DC) signal with high accuracy and minimal distortion. It is used to obtain a perfect DC output from a sinusoidal input waveform.
A precision rectifier uses diodes and operational amplifiers to rectify an AC signal. The diodes allow current to flow in only one direction, while the operational amplifier amplifies and inverts the signal to produce a positive output. This results in a DC output with the same frequency and amplitude as the AC input.
The main advantage of a precision rectifier is its ability to accurately convert an AC signal to DC, without any distortion or loss of information. It also has a fast response time and high precision, making it useful in applications such as signal processing and measurement.
Precision rectifiers are commonly used in power supplies, instrumentation, audio amplifiers, and other electronic circuits that require a clean and stable DC output. They can also be found in systems that perform mathematical operations on sinusoidal signals, such as Fourier analysis.
One limitation of precision rectifiers is that they require a precise and stable DC power supply for their operation. They also have a limited frequency range and may introduce small errors in the output due to diode and amplifier imperfections. Additionally, they may not be suitable for converting highly distorted or non-sinusoidal signals.