Seeking Recommendations for Budget Oscilloscope for Switching Converters Design

[hamza zughibi]

Hi everyone,

my English writing is bad so I used chat GPT sorry for that 

I'm an electrical engineer diving into the world of switching converters design and I'm in need of a budget-friendly benchtop oscilloscope to aid in my projects. I've been researching various options, but there are so many choices out there.

Can anyone recommend a reliable and affordable oscilloscope that would be suitable for working on switching converters? I'm particularly interested in a model that offers good performance, sufficient bandwidth, and perhaps some additional features that would be beneficial for this specific application.

If you have personal experience with a particular oscilloscope in this context, I'd love to hear your thoughts and any tips you might have. Also, if there are specific specifications or features I should prioritize for switching converters, please share your insights.

Thanks in advance for your help!

[tggzzz]

It will probably be cheaper to buy new HV differential probes and use those with any cheap oscilloscope.

[kimballa]

Pound for pound, if you're buying a new scope, I think the Siglent 2104X / 2104X+ scopes are the best value for money.

They have a lot of features normally only available on scopes 5x their cost, and work well. There's also plenty of advice on how to buy one of the base 100MHz models and, er, liberate the higher bandwidth and other options. (And 100MHz is already plenty of bandwidth for power system design, unless you're designing a power system for your own 5Ghz wifi base station.)

I got a 2104X+ this past summer and it's been great to use. Bode plot tool has been very helpful for the audio system work I do.

There's a power analyzer software module for it too, although you'll also need to buy a separate set of current probes (true for any power analysis though).

[pdenisowski]

I'll second tggzzz's comment about needing a set of high voltage differential probes.

In my opinion, the most important thing is to be sure that you get a scope with enough bandwidth for your slew rates / rise times.  There are lots of other things you could look at, but I think HV differential probes and sufficient bandwidth are the most important ones.

[tggzzz]

Pound for pound, if you're buying a new scope, I think the Siglent 2104X / 2104X+ scopes are the best value for money.

How suitable are they for the OP's requirements, SMPSs? Frequently those involve:

• high voltages
• direct connection to high-energy source (i.e. the mains)
• can't connect a probe's shield to an ungrounded point (please don't suggest isolation transformers and similar)
• multiple "reference" voltages, e.g. simultaneously measuring V_ds and V_gs of both high-side and low-side transistors

[pdenisowski]

How suitable are they for the OP's requirements, SMPSs? Frequently those involve:

• high voltages
• direct connection to high-energy source (i.e. the mains)
• can't connect a probe's shield to an ungrounded point (please don't suggest isolation transformers and similar)
• multiple "reference" voltages, e.g. simultaneously measuring V_ds and V_gs of both high-side and low-side transistors

Indeed, although there aren't many scopes out there that have isolated channels (we make one - the RTH handheld oscilloscope).  As you mentioned above, a differential probe is probably more important than the scope itself, since that would address all of these points*

*And help keep the OP from electrocuting himself and/or destroying the scope

[tggzzz]

How suitable are they for the OP's requirements, SMPSs? Frequently those involve:

• high voltages
• direct connection to high-energy source (i.e. the mains)
• can't connect a probe's shield to an ungrounded point (please don't suggest isolation transformers and similar)
• multiple "reference" voltages, e.g. simultaneously measuring V_ds and V_gs of both high-side and low-side transistors

Indeed, although there aren't many scopes out there that have isolated channels (we make one - the RTH handheld oscilloscope).  As you mentioned above, a differential probe is probably more important than the scope itself, since that would address all of these points*

*And help keep the OP from electrocuting himself and/or destroying the scope

Just so.

I have a  £200 THS720, about the cost of an  HV differential probe 

But it is easier to buy those probes, and they are easier to ship around the world.