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Reverse current into DC/DC or LDO

A generic regulator only sources current, and will source curtent to keep the output voltage at the setpoint. They do not, generally, sink current to bring voltage down to the setpoint. So if your ...
Justme's user avatar
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0 votes

Does mobile charger and buck converter have any basic difference?

Does mobile charger and buck converter have any basic difference? A mobile charger is typically a (fairly) isolated power supply, while a buck converter typically shates it's input and output grounds....
Math Keeps Me Busy's user avatar
2 votes

How to tell if buck converter outputs are isolated?

A buck converter is per definition not isolated. For the broader term of converter being able to down-regulate but with transformer (and transformer ratio), it would be a forward type converter.
winny's user avatar
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4 votes
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Buck converter has low frequency ripple with high amplitude

This is "PFM" mode, or pulse frequency modulation. At light loads, instead of keeping the frequency constant, the converter enters a hysteretic mode where it switches only when the output ...
John D's user avatar
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2 votes
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Custom buck converter putting out 1V instead of 5V

C15 isn't connected properly. It should go between the BST (pin-6) and SW (pin-5) pins. This is the bootstrap capacitor which provides the level-sifted voltage necessary to drive the high-side ...
qrk's user avatar
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1 vote

Circuit to convert 14.8v battery with max 4a discharge current into 12v, 9v and 5v output?

To reduce unwanted interactions (e.g., motor noise vs. control circuits), it's an advantage to have three separate power supplies. One might derive a 5 V supply from the 12 V rail with resistors and ...
DrMoishe Pippik's user avatar
1 vote

AOZ2261 Buck Switching Regulator doesnt give reasonable Output

The IC can't work with VCC = 3.3V because UVLO threshold for rising VCC can be as high as 4.5V. Apply 5V to VCC pin. The datasheet recommends VCC = 5V which is the voltage that the IC is characterised ...
Rohat Kılıç's user avatar
1 vote
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Can I use one 12 V 8 A power supply to provide 5 V 10.5 A power via buck converters?

That will work just fine. The buck converters will need to be at least 52.5/96 = 54.7% efficient, which is such a low requirement that practically any buck converter on the planet can do it. The Pi 4B ...
Jonathan S.'s user avatar
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2 votes
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Using capacitor with voltage rating close to input voltage

If you take the ISO-16750 standard (electrical standard for road vehicles) as a reference, or if it's a must for your project to meet, then the input voltage capacitors' voltage rating should be ...
Rohat Kılıç's user avatar
0 votes

Buck converter with external reference voltage?

Any linear or switching regulator with an accessible feedback can do this. I didn't draw the regulator, but suppose Vout is the output voltage, R1 and R2 form the feedback divider, and the regulator ...
bobflux's user avatar
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Using a capacitor to handle the inrush surge power of a fridge

You're likely to need quite a large capacitor to start the fridge, but not as extreme as those capacitor banks you see people use for starting cars. But the first thing to check would be to try the ...
Jasen  Слава Україні's user avatar
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Buck converter with external reference voltage?

A circuit based upon the feedback circuit below may or may not suit your needs. simulate this circuit – Schematic created using CircuitLab The output of the feedback circuit \$V_{fb}\$ is given ...
Math Keeps Me Busy's user avatar
1 vote

Buck converter with external reference voltage?

Probably more complex than you'd like but the LTC3886 can be digitally programmed (I2C). It has 12-bit digital programmability of output voltage of 2 to 13.8V in 4mV steps and 16-bit digital readback ...
Spehro Pefhany's user avatar
0 votes

Can I connect buck boost converters back to back?

You may want to consider using a battery charger IC with the ability to seamlessly switch between DC input and battery input. It is normally called dynamic power management (DPM) and dynamic power-...
VBwhatnow's user avatar
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3 votes

State-space average model of non-ideal buck converter

i myself struggled with this too. I will show how to derive the equation for a system only containing the ESR resistor for the Inductor and capacitor, as these are the parts bringing some ...
Jakob's user avatar
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3 votes

What is the purpose of the Zener diode in this voltage smoothing circuit?

As far a depictions go, I'd draw the circuit as follows: simulate this circuit – Schematic created using CircuitLab This makes it perhaps more obvious that R1 is dropping down voltage, and that ...
Kuba hasn't forgotten Monica's user avatar
4 votes
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What is the purpose of the Zener diode in this voltage smoothing circuit?

This circuit is not generally looked at as a low pass filter but as a regulator with bypassing. The Zener and resistor are used as a shunt voltage regulator. The capacitor is to bypass the regulated ...
GodJihyo's user avatar
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3 votes

I assume that AOZ1280 buck converter misses datasheet specs

I found similar behavior with low input voltage (abt. 4,5V) and output to be 3,3V when using AOZ1280. I found saw-tooth from 0V to 3,3V on output. Oscilloscope shows recurring voltage breakdown at ...
G. Hippchen's user avatar
3 votes
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TL494 step-down converter high voltage LTSpice

You are using an N channel MOSFET and that requires a driver that is boot-strapped: - Unfortunately, you don't appear to have implemented boot-strapping correctly. For instance, consider this circuit ...
Andy aka's user avatar
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0 votes
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Synchronous buck converter using gate driver IC

Why am I seeing some discrepancies between measurement and expected value of output? When I set duty cycle 50% and fsw = 20kHz, I expected output to be around 7.5V and 100mA with the load of 75 ohm. ...
Andy aka's user avatar
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Synchronous buck converter using gate driver IC

If a buck converter worked according to Vout = Vin*duty cycle (continuous mode) without a control loop, there wouldn't be a need for a control loop at all. In reality, the switches have resistance as ...
John D's user avatar
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