[spatular]

I've yet to see a voltage regulator IC with built-in caps. DC-DC modules sure, but author argues that this kind of info (module / ic) should be present in schematics. BTW, some linear regulators can't handle ceramic and low-ESR capacitors at output, and may be better with none if that's the choise.

[rightbyte]

I hate to maybe be proving his point by showing that I'm not into the EE field and thinking of a board mounted DCDC-converter as a voltage regulator (which it is but not what you usually call it in english?)

I would still argue that logic IC have alot of internal pull ups. Or that eg. "Reset sequence of digital component is wrong" is a bad whiteboard question.

[spatular]

I believe that without qualification "linear regulator" could be just anything that regulate voltage. Usually you can easily tell from schematics around it if it's some switching IC, an LDO or a module. And if you have layout or 3d render of the board it'd be almost certain.

Otherwise the person may just ask: "where are caps, or is this thing a module or what?"

[msds]

No, a linear voltage regulator is well understood as something with a transistor pass element in linear mode and a (probably dumb) control loop.

Definitely not a switcher or module, could be an LDO.

[mkeeter]

In my experience, "linear regulator" refers specifically to voltage regulators which drop from a high voltage to a lower voltage by burning all of the power in between (e.g. the venerable 7805).

They're useful if the voltage drop isn't too large and/or if you need a particularly stable output voltage; contrast them with switching regulators, which are more efficient but have some amount of output ripple.

One design that I worked on used a switching regulator to generate 5V, then linear regulators to generate something like 3.7V and 2.9V for various sensitive analog circuits.

[kragen]

No, switchers aren't “linear.” And on a schematic the regulator isn't going to be a box labeled “regulator”! It will have a part number, probably a familiar one.

[spatular]

Sorry, I meant to write "voltage regulator" about which parent asked about, not sure how I ended up with "linear regulator".

[kragen]

Yeah, a switching regulator is still a regulator.

[sitkack]

ICs with multiple power domains have a boot sequence that must be followed or the IC isn't in the proper state. Many interview questions fall into the "assumed assumptions" category. Simply saying, "lets reset to a known good state and modify one variable at time disqualifies many candidates". Because we don't teach science like we should. We should be teaching the scientific method before we teach the three Rs.