No, I have a couple of adjustable power supplies, but they are not lab quality instruments. Perhaps we are using the term differently.

Most of my projects are powered by phone chargers or 12-24V bricks.

To me, a "lab PSU" is a product advertised as a, wait for it, a "lab PSU". Not to sound stupid or anything, but really, what else would you use to categorize them? They have banana plugs. They try and achieve low noise. They output either voltage or current at a regulated limit (the fancy ones can do wattage too.)

That being said, "lab quality" depends on the lab. A lab at TSMC will need much better microscopes than a lab in the back of a doctor's office.

Personally, when choosing T&M equipment, I try and find the happy medium between price and performance. Typically, there's a curve you can see if you plot the various metrics and features with respect to price and you'll normally want to be at the "toe" or before the "toe" if you can.

 

To me, a "lab PSU" is a product advertised as a, wait for it, a "lab PSU". Not to sound stupid or anything, but really, what else would you use to categorize them? They have banana plugs. They try and achieve low noise. They output either voltage or current at a regulated limit (the fancy ones can do wattage too.)

That being said, "lab quality" depends on the lab. A lab at TSMC will need much better microscopes than a lab in the back of a doctor's office.

Personally, when choosing T&M equipment, I try and find the happy medium between price and performance. Typically, there's a curve you can see if you plot the various metrics and features with respect to price and you'll normally want to be at the "toe" or before the "toe" if you can.

A heuristic for Pareto Optimality, the 80/20 rule, has served me well and seems to be a close enough approximation of reality to be akin to called a “rule”. It can be stated in various ways, but the one I settled on is:

80% of the result costs as much as the other 20%
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In this case, “cost” means any work involved whatever the form. This can include time, money, physical size, or pretty much any target of a design. It is why unless you actually need that last 20%, there isn’t a rational basis for demanding it.

As loose as this concept is, it has been practically indispensable in my various careers. It is a way to cut to the heart of things with so close an approximation of ideal that even if I couldn’t spend the time to analyze further I can count in the fingers of one hand when it let me down.

 

Low pass filters have been used in power supplies forever. The capacitor across the diode bridge in old style transformer supplies is a low pass filter. No, using low pass filters is not new.