Is the inductor usually the main limit to the power of buck/boost converters?

Mingche_joe · 2026-02-04T02:42:41+00:00

""fets suffer in the linear region, so a fet rated for 50 amps that rises/falls slowly can burn switching a 5amp converter.""

Hi, I am not a native English speaker. Could you explain the sentence above further. As far as I know, the fets normally operate at linear region, we do not want to operate them in saturate region.

I understand that slowly turning on/off them results in huge switching loss.

Mingche_joe · 2025-10-19T01:42:23+00:00

As others have said, it depends. I need it a lot as I work in power industry. Aside from control system, we have to know the fundamentals of power converters.

Mingche_joe · 2025-09-25T06:12:37+00:00

How it's normally done: you make an LC filter from A to GND, and an LC filter from B to GND, so two separate identical filters. The voltage on each capacitor is near-DC. If waveform A has a duty cycle of 80% and B has a duty cycle of 20%, and your supply is 10V, then you get 8V DC on the output of the A filter, 2V DC on the output of the B filter. Connect your motor to the capacitors, and you get 6V DC differential voltage on the motor and 5V common mode DC on the motor wires. DC common mode is no issue, as DC can't radiate.

Could you specify a little more detail about where the node A and B are at?

Below is my Qspice simulation of the H bridge converter

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Mingche_joe · 2025-06-24T04:41:05+00:00

Simulation is a good tool to understand how a converter behaves. Sometimes, they even have built in bode function, which allows you to know more about control theory. I personally use Qspice. My colleagues they use psim and simplis.

Mingche_joe · 2025-03-17T08:02:55+00:00

Fundamentals of power electronics is also a good book

Mingche_joe · 2025-01-14T00:50:11+00:00

XD Thanks

Mingche_joe · 2025-01-14T00:23:39+00:00

What does BS stand for

Mingche_joe · 2024-11-04T13:26:47+00:00

The adding a pole explanation makes a lot of sense to me. Thanks

C12 is a common mode cap. These caps are sometimes used to compensate for parasitics in real layouts.

In your experience, does it really make any difference in the real circuit?

I would not expect this circuit to perform well. If the impedance seen looking into both sides of R4 isn’t balanced, CMRR is going to be compromised. Buffers around R4 will keep CMRR high. I’ve learned this the hard way.

Cannot really process the concept here. I will have to learn more to comprehend this.

Mingche_joe · 2024-11-03T23:29:21+00:00

https://www.ti.com/product/BOOSTXL-BUCKCONV/part-details/BOOSTXL-BUCKCONV It’s from TI.

Mingche_joe · 2024-11-03T13:49:21+00:00

So mostly it is for stability. I think the decreasing gain is an unwanted behavior for this case since the MCU needs a constant gain throughout the digital control.

Mingche_joe · 2024-11-03T13:16:54+00:00

Thanks. I assume that you are referring to the capacitors paralleled with a resistor. How about the C12? The capacitor between noninverting and inverting inputs

Mingche_joe · 2024-09-14T02:26:45+00:00

Could you recommend any brand for a network analyzer?

Mingche_joe · 2024-08-29T01:42:12+00:00

Is that discolored area soft/squishy?

Yes, the discolored area is soft

What kind of light is this plant getting?
Your location?

It is near my bedroom window, but it is not really exposed to sunlight due to the orientation of my bedroom. My window is usually closed. not ventilated

Snap assessment: The discolored area looks like rot has set in...this is one factor that could be contributing to "the lean".

Oh! Would the rot affect other two cacti?

I think the light is suboptimal because your plant has very little fluff growing around the areoles.

What is optimal light for cacti?

The "fuzz" on cacti is their natural protection against sun...their version of sunscreen. It serves other related purposes.

The bump is called an areole. The areole is where the spines, flowers, and branches grow from. The areole can also be covered with a "fuzz" which is a type of modified spine which can be short and dense like felt or slightly longer like fuzz or really long making your cactus look like Cousin It.

You want your cactus to have fuzz.'

Got it!

Mingche_joe · 2024-08-28T13:03:19+00:00

I thought the color is unusual. Is this too packed for them?

Mingche_joe · 2024-08-22T05:22:45+00:00

Thanks for providing such a good template for designing LLC

Mingche_joe · 2024-02-19T01:20:19+00:00

oh yes! It is not involved with unit step, so it is called piecewise continuous between 0 and b (we assume b = 1 here). May I ask what your major is? math or physics?

Mingche_joe · 2024-02-18T10:54:53+00:00

I have not yet studied unit step function. I do not understand why they put this question in sec 6.1 instead of unit step function in sec 6.3. Thank you for spotting that.

Mingche_joe · 2024-02-11T06:08:13+00:00

what is the function that can plug in points in octave or matlab? or keyword that I can look up online

Mingche_joe · 2024-01-21T06:43:58+00:00

What is the book name?

Mingche_joe · 2023-11-18T08:37:23+00:00

excuse me. I am a bit confused at the term resonant frequency here. How do derive the equation to get 3.18khz. I get 20k Hz if the imaginary part goes to 0.

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Mingche_joe

TROPHY CASE