| Electronics > Projects, Designs, and Technical Stuff |
| 500KHz peak detector |
| (1/2) > >> |
| ricko_uk:
Hi, I have to make a peak detector of up to 500KHz. Using some of the classic configurations require a more expensive (high speed high slew rate op-amps). I have come across a comparator-type peak detector below but it start introducing error at 100KHz Any other suggestions for higher frequencies up to 500KHz? Or at the absolute minimum 250KHz? Many thanks :) |
| graybeard:
what is the range of signal amplitudes? do you need both positive and negative peaks? what are the source and load impedances? you need to define your requirements more completely |
| vk6zgo:
An old style "peak & hold" detector can work up into UHF, but may have limitations, in that very fast peaks in the midst of a lower frequency signal may be missed. If you need to detect rarely occurring transients, you are pretty much stuck with doing it digitally, & will need a very high sample rate, plus a lot of memory. If the transients you want to see are very infrequent, maybe the device could check what it has "seen" for a set previous time, flag that as "no transient found", empty & re-use the memory. |
| Circlotron:
Precision AM detector? I have a circuit at home I'll post later. |
| ricko_uk:
Thank you Circlotron and Greybeard, Circlotron, look forward to it. Thank you! :) Greybeard, - signal amplitues as mentioned from few tens of mV to 4.5V. It depends on the configuration for every specific application. Most cases are between 1.5 and 4.5V. - the signal is as just a fixed sinewave - detection of both positive and negative but no need to differentiate (i.e. a full wave rectifier would solve that) - source and output impedances are buffered with op-amps so generally speaking at this stage no major issues there that I can think of Thank you both :) |
| Navigation |
| Message Index |
| Next page |