Questions tagged [buck]
A non-isolated DC-DC converter topology which outputs a voltage less than or equal to the input voltage.
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Best power supply configuration
I'm making a power supply board with a buck converter for a 2A maximum and I would to know which is the best configuration between these two:
Is it best to put the input filter, a parallel damped LC ...
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Input impedance of a buck converter
Is there an approximate formula for calculating the minimum value of the input resistance (or impedance) of a switching regulator? I found several formulas but can't figure out which one to choose. I ...
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5 V to 3.3 V buck with limited input current and large capacitor to cover current spikes?
We need to design a power supply for a 3.3 V WiFi-device. But there are quite some current spikes during WiFi startup. Using the design below there is a risk the 5 V (250 mA max) supply (not mine) ...
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Does DC-DC 24V-12V waste less power than AC-DC 220V-12V?
I am modifying an existing UPS to allow for a longer backup time. I plan on adding a cooling fan along with an external current controlled power supply to charge the larger batteries. There are some ...
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Input filter for switching regulator
I'm trying to create an input filter for a switching regulator for automotive application.
My aim is to make a supply board, where from 24V come out 12V (from the buck) then 10V and 5V (from two LDOs)....
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Best way to control large buck converter?
I am looking for a faster way to control output voltage for a buck converter.
This buck converter has its own fet driver and I am not willing to change it. I really only need the signal to run the ...
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DC-DC buck converter inductor current
Draw a simple dc to dc buck converter fed with dc voltage of constant magnitude (= E). The
converter supplies a resistive load (=R). Draw the shape of voltage waveform across the
freewheeling diode. ...
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Cooling IAUC90N10S5N062 MOSFET from the top
I design a sync - buck converter, and I need to cool down my top side and bottom side MOSFETs. For mechanical reasons, it is easier for me to place a heat sink on top of plastic housing of MOSFETs (...
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How do I properly import a .lib description into a LTspice symbol?
I am trying to simulate the TI part TPS62808 in LTspice, Pspice for TI, and Tina TI. I managed to easily run the simulation in the latter two simulators, but the models were specifically made for them,...
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POE circuit with small transformer and small volume footprint
I would like to make an isolated POE802.3af controller that can convert POE ~48V to 5V 2A, but the main problem is most designs use a standard POE transformer that has multiple coils. The problem with ...
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I need to make a separate buck and boost converter with 200W power rating
I have to make two converters. One buck going from 240VDC to 12VDC 30 amperes and one boost from 12VDC to 24VDC, possibly with the ability to change from 6 to 30 amperes.
A few more details: The buck ...
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Why is there a negative source voltage when the MOSFET is off in this buck converter?
This is the voltage source. As you can see, when there is a turn-off phase, I have a negative source. Why?
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Buck converter with some big ripples
I am simulating a buck converter (schematic at the end) (datasheet) and I observe bigger spikes in addition to the normal ripple. In the screenshot below, Vout is in green and the buck converters SW ...
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Can a single buck converter be used for converting both 12V and 24V input to a constant 12V output DC to be fed into a 12V DC motor?
My target is to design a low-cost PCB to run a 12V DC motor. I do need to have 2 input sources, a 12VDC and a 24VDC. What is the best way to achieve this using a single board? Can I use a single buck ...
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Problems with buck converter
I designed a PCB with two LM61495 buck converters. They should produce a 3V3 and 5V output. However, for both circuits, the output is 12V. The picture below shows the output of one of the channels ...
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