Finding a Good DC Peak Detection Circuit

[propergomper]

hi i was wondering if anyone could tell me of any good dc peak detection circuits. the voltages i am measuring are varying by one hundredth of a volt.
i have been using the peak detector on the wqikipedia website but the circuit doesn't seem to store the peak voltage as the reading on the dmm drops once i change the conditions of the circuit

any help is greatly appreciated

thanks

 

[berkeman]

The one at wikipedia.org is the correct basic one to use:

http://en.wikipedia.org/wiki/Peak_detector

Remember that unless you reset it, it should hold the peak value until the load resistance (your DVM?) bleeds off some of the charge on the storage capacitor. If you want longer hold times, you need to increase the capacitance (within reason), or raise the load impedance (maybe use a FET input opamp buffer stage?), or do some kind of sampling of the output voltage and store those values digitally somewhere.

 

[ravenprp]

There are several factors to consider when choosing a good DC peak detection circuit. The first is the accuracy of the circuit. Since you are measuring voltages that vary by one hundredth of a volt, it is important to have a circuit that can accurately detect and store these small changes. The peak detector circuit on the Wikipedia website may not be the best option for your needs, as it may not be sensitive enough to capture these small changes in voltage.

Another important factor to consider is the speed of the circuit. If you are measuring fast-changing voltages, you will need a peak detection circuit that can keep up with these changes and accurately store the peak voltage. Some circuits may have a delay or lag time, which can affect the accuracy of the measurement.

You may also want to consider the complexity of the circuit. Some peak detection circuits can be quite simple, while others may be more complex and require additional components. It is important to choose a circuit that is suitable for your skill level and available resources.

One option you may want to explore is using an op-amp based peak detector circuit. These circuits are known for their accuracy and speed, and can be easily customized for your specific voltage range. Additionally, there are many resources available online that provide step-by-step instructions and diagrams for building op-amp based peak detectors.

In conclusion, when looking for a good DC peak detection circuit, it is important to consider factors such as accuracy, speed, and complexity. It may also be helpful to do some research and consult with experienced individuals to find the best circuit for your specific needs. Good luck with your project!