All Questions
Tagged with buck switch-mode-power-supply
47
questions
9
votes
3
answers
4k
views
Snubbing DCM (nonsynchronous) Buck converter
FINAL UPDATE:
I've posted an outcome report below. I'm very satisfied with how this has come out and I learned a lot in the process. More details and before/after shots in the answer below. Thanks to ...
- 7,172
2
votes
1
answer
3k
views
Relationship between switching frequency and controller's crossover frequency in buck SMPS
Context: tuning the control loop of a buck SMPS. I specicifally have a TI TPS40200-based circuit in mind, but I think this applies to SMPS design in general.
Quoting from Type 2 compensation network:
...
- 320
1
vote
1
answer
691
views
Is there a good topology for splitting a DC power supply from a few LM2576 and LM2577?
So, this isn't the most serious project, more of a toy/hack, but I have a some LM2576 and LM2577 and I wanted to see if I could somehow get an adjustable dual rail (bipolar) supply out of them, for ...
- 793
10
votes
5
answers
876
views
MOSFET failure in a high power AC-DC SMPS buck converter
I've made a AC-DC step down buck converter that converts 220 VAC to a variable 45 to 70 VDC at 5 to 10 A to charge a Li-Ion battery. I'm currently using ESP32 to drive a MOSFET driver (IR2110) to ...
- 101
2
votes
1
answer
1k
views
Input filter to reduce conducted emissions caused by DC/DC converter
This material from ROHM explains the input filter design for a DC/DC converter.
The filter circuit is given below.
I understood the design of Lf, Cf2, Cd and Rd.
If you see the 3rd page (design of ...
- 2,593
19
votes
6
answers
14k
views
Why do buck (step-down) switching regulators require an inductor and diode?
So, I understand, at least at a basic level, the method of operation of switching converters, both buck and boost. What puzzles me, though, is why buck converters in particular aren't simpler.
Why ...
- 7,749
15
votes
3
answers
2k
views
Why did my DC/DC Buck Circuit fail?
I'm in the process of debugging a PCB I made. On this board, a 24V input feeds through a DC/DC buck circuit (based around the TI TPS54202DDC) to output 11V, then an LDO to output 9V (to ensure a very ...
- 671
8
votes
3
answers
1k
views
Critique my SMPS buck design
I'm using an LM2734 buck regulator to get +3.3V at 400mA. The datasheet is unclear on how to lay out the supply, so I tried to follow some common sense, keeping all power traces short where possible. ...
- 31.9k
4
votes
1
answer
636
views
Can a synchronous regulator "chirp" in burst mode?
I'm looking at (the millions of) buck regulators available for a project where the board will be a host board for a Gumstix Dual Cortex A9. This can pull quite a bit of current at maximum so I was ...
- 2,588
4
votes
1
answer
877
views
Why 2 diodes in parallel buck converter design?
I have been looking up dc-dc buck converter designs and have question regarding the diodes.
It says "5A High current Schottky diode" is it common in buck converter design to parallel ...
- 127
3
votes
1
answer
717
views
Is it useful to think of SMPS input capacitance as part of an LC filter?
I'm at the stage of learning about switched-mode power supplies that I'm focused on understanding the role of input capacitance. Just for background, I'm working with a buck topology for this ...
- 7,172
2
votes
2
answers
2k
views
switching noise from ltc3780
I have currently built a buck-boost converter using LTC3780 on a breadboard following this deisgn.
The circuit is calculated and designed to accommodate the input voltage given in the schematic. I ...
- 21
0
votes
2
answers
1k
views
Calculating inductor value for my buck converter [duplicate]
I'm trying to understand the SMPS operation.
The goal is to select inductor (L1) & capacitor (C1) values that satisfy the working condition below:
V1: 22-26 V range.
Power supply required: 1 A.
...
- 13
18
votes
1
answer
17k
views
How important is self-resonant frequency for an inductor when used in a fast (~3MHz) buck SMPS?
I'm using the LM2734Z, a 3 MHz buck regulator. It's really fast which means it has a small inductor.
One of the things I'm wondering is how important is the self-resonant frequency of the inductor? I'...
- 31.9k
14
votes
3
answers
3k
views
High current buck converter has excessive ringing and poor regulation
I am designing a power supply to power two fiber-coupled diode arrays for a solid state laser. The diode arrays need a current controlled source of about 50 A and will have a voltage drop of < 2.2 ...
- 237