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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Miyuki on April 29, 2016, 02:38:55 pm

Title: Differential probes vs insulated channels
Post by: Miyuki on April 29, 2016, 02:38:55 pm
Hi I'm no sure where to post this question

I want to discuss about pros and cons of this two solutions:
Differential probes vs insulated channels

Even DIY probes and triggering two insulated scopes

What is strong and weak sides of this two ways ?
Title: Re: Differential probes vs insulated channels
Post by: Marco on April 29, 2016, 08:17:12 pm
There are multiple styles of differential probes.

Compared to most high voltage differential probes using a scope with insulated channels will have lower noise, because high voltage differential probes generally have a 100x divider at the differential inputs.

Low voltage high speed differential probes often do their differencing near the probes, this allows them to put a much smaller capacitive load into the circuit you are measuring compared to a normal scope probe (insulated channel or not).
Title: Re: Differential probes vs insulated channels
Post by: tautech on April 29, 2016, 08:40:54 pm
Hi I'm no sure where to post this question

I want to discuss about pros and cons of this two solutions:
Differential probes vs insulated channels

Even DIY probes and triggering two insulated scopes

What is strong and weak sides of this two ways ?
What are your real test requirements?
Title: Re: Differential probes vs insulated channels
Post by: bson on May 01, 2016, 06:25:03 am
If you already have a scope, then an inexpensive low-bandwidth (say, 25MHz) HV differential probe will let you freely probe a power supply using your existing scope.  A bench scope will likely have a better screen, higher bandwidth, higher sample rate, more channels, digital MSO features, more memory, more compute power, and cost less than a handheld.

A high-bandwidth, low-voltage differential FET probe on the other hand is a completely different animal that will be cumbersome to use without a full-featured scope with an intelligent probe interface.