Too much complexity without any benefit (when adjusted for new failure cases and cost of additional components and complexity).

Electronics is mostly KISS, not only motivated by the financial factor but also reliability, manufacturing, etc.

So far micro controllers are too expensive, too sensitive to unstable power supply, too complex in general (requiring some support components in some cases, have an additional prefabrication step for flashing firmware by the chip vendor, and cost a lot more.

There is no clear advantage to the approach you mentioned.

The "new failure cases" it adds are rather exciting -- if the MCU locks up or glitches, which they are prone to, then it could short the supply rails and blow the switching transistors, or destroy the connected load by overvoltage. Analog control ICs, while they are not 100% reliable either, have many safeguards built-in that can react nearly instantaneously and don't depend on the relatively complex process of executing machine instructions.

There are plenty of systems where a software failure leads to permanent hardware failure. This would just be one more.

The main benefit is probably a wider flatter efficiency curve. Instead of saying "this power supply is 98% efficient when delivering 1 Amp (but more like 80% efficient at 0.1 amps or 2 amps), the power supply can adjust the switching frequency to trade off switching losses and output ripple for efficiency if the application allows.

I've come across a broken laptop before that had a complex power control computer like what you've described.

I ended up repairing it by hard-resetting the NVRAM and forcing the power control computer back to its initial "reset" state.

This was a common enough problem that the manufacturer had a step-by-step guide showing how to fix it on their website.

The moral of the story is that adding complexity, even when that complexity is designed to increase robustness, usually just means that there are more systems that can fail.

Well, your ARM-powered chip will need some analog-to-digital converters since the feedback signals are analog. And you'll need a high-current output driver to control the switching transistor. And some sort of startup circuit to provide power before the processor starts running. And an undervoltage lockout circuit to prevent the processor from malfunctioning if the voltage drops. So you still have a bunch of analog circuitry but you've added an analog-to-digital converter and a microcontroller. There are some applications where this tradeoff makes sense, but in a lot of cases it would just be excess complexity.

You can use an MCU as a controller. Here's an example.

https://youtu.be/m8rK9gU30v4

The problem is that you can't make every controller with an MCU, and you can't always make a competitive controller with an MCU.

There are already controller ICs that are configurable. In fact, modern controllers are a mix of analog and digital hardware. They do everything an MCU would do in that situation, but faster, less invasively, and with less power. Often, they do more than an MCU because they're not slowed down by an instruction cycle.

See my comment before last for an example of a software-configurable hardware controller.

Condition monitoring is a thing, and it's done with MCUs, DSPs, and FPGAs. But controllers sit on the non-isolated side of the gate driver, where they have basically no physical access to any useful signals. That's why condition monitoring is separate.

The lookup table idea is used for motor control. It's called a firing angle table. But that's a slower application.

This is definitely happening in onboard power management for systems with batteries. I suspect it's just big generic PSUs that stick to old analog ASICs.

Not self-tuning, though, they have to be tuned and all that software written.

Dedicated PMIC chips will be mixed signal, with digital control and analog failsafes.

Before switching ICs became ubiquitous it was common to roll your own with an 8-bit micro. It isn't cost effective now because of the additional external components, board area, and NRE you'd need vs the single chip solution.

I was actually looking into that this week due to chip shortages... it is not cost effective, but if the alternative is sitting and waiting a year for the specialized switch controller to become available again, that NRE doesn't look too bad.

TI makes some DSP chips with a dedicated peripheral (basically just a high resolution timer with some fancy capture/compare units) for doing PWM for power supplies.

Supposedly it can also detect shoot-through and modify timing to compensate.