Electronics > Projects, Designs, and Technical Stuff
20mV Enough for Power Supply Design?
PixieDust:
I'm starting the design of a power supply and was wondering whether my oscilloscope's 20mV (20 milivolt) per division minimum ? Resolution? will be enough?
Also, most likely it will be a switching power supply. I don't have x1 probes, what bandwidth will I need to look for?
Kleinstein:
Working with only 20 mV/div and than a times 10 probe could be a little tricky. For low impedance signals, like the supply output one could get away with just a coax cable and a 50 Ohms termination, as a kind of poor man x1 probe.
Speed wise is would be nice to have some 10 MHz BW at least. Much slower can become tricky and may higher some details. It would be still better than no scope.
PixieDust:
Yep I found this article on the topic by Tektronix:
http://www.tek.com/dl/51W_27668_0_MR_Letter.pdf
great resource, covers a lot. Was mostly wondering whether my scope will be up to the task (given that modern scopes appear to be able to have 1mV per division) and also what x1 probes to get.
Thanks, will look for at least 10 MHz probes.
amyk:
What voltages and precision?
ejeffrey:
20 mV / division is pretty poor. 2, 1, and even 0.5 mV / div are pretty common. Of course it is better than no scope at all but it really limits your measurement flexibility especially when it comes to using high impedance probes.
Whether it is suitable for a particular task is hard to say without knowing the details, but generically I wouldn't say such a low resolution scope is adequate for general use these days given all the much better options available so cheaply.
Navigation
[0] Message Index
[#] Next page
Go to full version