EEVblog #490 - Peak Detector Circuit
Why Electrical Engineering Stack Exchange recommends it
Electronics Stack Exchange answerers point people to it as the standard video explanation of peak detector circuits, and askers cite it as the basis for their own designs.
Recommended by 4 people across 4 different months, 2014 to 2021.
What it is
Dave Jones of EEVblog walks through how to design and measure basic and precision opamp peak detector circuits, in a 'Fundamentals Friday' episode. He covers the simple diode-and-capacitor version and then opamp-based designs that compensate for the diode drop.
What people said
Recommends Nick Alexeev · 2014-10 · Electrical Engineering Stack Exchange · on “Simplest possible way of latching the voltage peak?”
I think, the type of a circuit that you are looking for is called peak detector . The simplest peak detector consists of a diode and a capacitor. The diode prevents the capacitor from discharging, so it retains the max voltage less the diode drop. The diode drop is a shortcoming of a simple circuit like this. It doesn't "see" voltages that are less than the diode drop. (That page where this snippet came from [LINK] is worth skimming through.) An OpAmp peak detector is more precise. It compensates for the diode voltage drop. ( source [LINK] ) There is a fair amount of information about peak detectors: EEVblog video [this video] , Planet Analog article [LINK] .
Recommends steffka · 2016-10 · Electrical Engineering Stack Exchange · on “Piezo input stage for drum triggering”
I want to design an input stage for my DIY midi-drum-trigger. Piezo-Elements are used as drum trigger and i want to read out the voltage spikes with the built-in ADC of a ATMega168p in order to generate MIDI-Signals. I checked different resources for how to design a input stage for the piezos, since they generate a very high voltage, but the circuits i found are very different. Here is a circuit i found at edrum.info [LINK] : [LINK] I am very new to electronics, but this is how i would explain the circuit: The potentiometer acts as a voltage divider and scales down the signal. The BAT85-Diode removes the negative portion of the signal. I don't know what the resistor in parallel to the BAT85-
Recommends Bimpelrekkie · 2018-06 · Electrical Engineering Stack Exchange · on “Need help analyzing a circuit?”
The circuit in the red rectangle is an AM detector or peak detector . The diode is an essential part of the circuit. The diode will conduct if the input voltage is higher than the voltage across the capacitor to ground on its right. Dave from the EEVBlog made a video about peak detectors, go watch it! [this video] Here the peak detector basically translates the amplitude of the audio signal (and more amplitude means louder) into a changing DC voltage to control the lights. The virtual ground circuit in the blue rectangle is a way to prevent having to use a symmetrical supply voltage. A symmetrical supply voltage could be for example +10 V, ground and -10 V. That requires a slightly more complex p
Recommends Peter Jennings · 2019-08 · Electrical Engineering Stack Exchange · on “Detecting signal / amplitude from 2 wire DC speaker”
It sounds as if you need a peak detector circuit. This can be as simple as a single diode and a capacitor. There's a very good video lecture over on YouTube here [this video] which discusses how it works and various forms of the circuit depending on what you want to achieve.
Cites Sparky · 2016-02 · Electrical Engineering Stack Exchange · on “Strange behavior from peak detector's certain op-amps”
I built a multiple feedback 2kHz band-pass filter with gain Vo/Vi = 4 and an envelope detector for this filter as shown in this great video tutorial EEVblog #490 - Peak Detector Circuit [this video] When i applied a 1v 2kHz square wave signal at the input of the BP-filter i got 4v peak to peak sine wave signal (2v positive and 2v negative).So far so good. For the peak detector, in the beginning, i chose two OPA379 op-amps. When i connected the output of the filter to the input of the peak detector and measured the filter's output and the demodulated voltage with the oscilloscope something strange happened. The filter's output was at 2v (positive peak) as i expected but The demodulated detector's
Cites Daniel K. · 2020-11 · Electrical Engineering Stack Exchange · on “How to make a peak detector circuit”
There seems to be no link to the video in the question, so here it is: [this video] "EEVblog #490 - Peak Detector Circuit"
Cites paulplusx · 2021-01 · Electrical Engineering Stack Exchange · on “Optimising a single pulse precision peak amplitude detector”
[LINK] So I made this precision peak detector circuit (with reference from EEVblog's video [this video] and experimenting with the resistor/capacitor values), with which I want to measure the peak amplitude of a single pulse of width 5us (50ns each rise/fall time at best and 155ns/90ns rise/fall time at worst) and the amplitude is variable and can be within 3mV to 3V. I would like the peak-detector to hold the voltage level for a sufficient amount of time (in this case around 60ms, although I have simulated up to 3s with the same result) without degrading the voltage level too much (a maximum of 1-2mV degradation over 60ms is acceptable for me). So the result of the above circuit looks good in th