All Questions
Tagged with dc-dc-converter converter
119 questions
0
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799
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Why is there a LC filter in front of the DC/DC converter?
I have to study this circuit. I understand that Graetz's bridge is there to convert the current to positive, but why is there a LC filter at the entrance of the converter?
- 473k
0
votes
0
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100
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Forward Converter analysis
I am having difficulties in finding the DC component of the voltage across capacitor C2 expressed in terms of Vg and duty cycle D. In the first interval (DTs) the current through C2 is zero, hence the ...
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2
answers
453
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Drop input voltage for a boost converter
I have a 21V DC solar panel power source, that feeds a DC-DC boost converter. I set the output voltage of the boost converter to 19.5V to charge my laptop, but since the input voltage is higher than ...
- 152k
1
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0
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120
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Synchronous boost light load operation and general SMPS terms
What are the differences between the skip cycle, pulse skipping, diode emulation, and forced PWM at general DC DC converter light load operations? How do they work and when do I want to use them? Page ...
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2
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857
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Average input current in forward converter
I am trying to understand how to calculate the average input current of a typical forward converter. If the converter has negligible magnetizing current, a large inductance and a turns ration of n1:n2:...
- 23.5k
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1
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389
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Transformer secondary winding resistance
I am struggling to understand how to model a resistance loss of a transformer secondary winding. In a typical flyback converter, if the primary and secondary transformer have a resistance loss, how do ...
CommunityBot
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6
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7
answers
8k
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How to reduce MOSFET heating in Buck Converter
I have designed this Buck Converter which convert 60VDC to 12VDC at 10A.
Switching Freq 100KHz.
Facing MOSFET too much heating issue.
MOSFET ON time and OFF time is decided by a UC3845B based circuit. ...
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4
answers
1k
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Generating 5V from 37V DC with no EMI
I'm making a PCB for an audio amplifier + power supply (circuit here).
The power supply voltage rails with my transformer end up being about +/- 37V, and I want to generate a 5V rail from this for ...
- 121
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3
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450
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Connecting two DC converter's inputs in series
I know it won't work, but I want to make sure I have the right explanation why it won't work.
Given are two devices which have a build in converter (I have this digital voltmeter in mind). They need ...
CommunityBot
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6
votes
3
answers
3k
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Understanding Boost Converter
Theres a very good explanation for the Boost Converter on Wikipedia. But it is a very mathematical explanation. How would you explain the Boost converter to a non Math person like me?
CommunityBot
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1
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Can we use DC-DC Buck convert installed 3.8v battery to power Phone continuously?
I have a Windows tablet whose battery is dead and I want to convert it to without battery to use as a digital photo frame.
Table dead battery is 3.8V
Can I use DC-DC Buck convert (DC-DC converter ...
- 73.4k
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2
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105
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Misconceptions about layout of DC to DC step-down converters
I have noticed, in my opinion, some misconceptions in the layout of the majority of DC to DC step-down converters.
I've seen in many PCBs that the trace that goes to the input of the converter (point ...
- 81.7k
6
votes
2
answers
5k
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Behavior of Boost and Buck Converters
I have a couple questions about boost and buck converters.
First, do they try to hold the output voltage constant, or do they alter the input voltage by a constant factor? For example, if I change ...
4
votes
1
answer
2k
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What dc-dc topology to use for a 300W step-up converter?
I am asked to design a dc-dc converter with the following specifications:
Vin=24V(2 lead-acid batteries in series), Vout=300V and Iout=1A.
My initial choice of topology was the boost converter. ...
CommunityBot
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0
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56
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How do I get a lower/higher voltage from a cuk converter?
By definition, "The Ćuk converter is a type of DC/DC converter that has an output voltage magnitude that is either greater than or less than the input voltage magnitude"
So I was wondering how I can ...
- 889
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1
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3k
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What is Pass Transistor?
What is pass transistor?. How does it work?.
while reading about the DC-DC converter, I came across Pass Transistor.
CommunityBot
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4
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1
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494
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Is there a problem using electrolytic (polarized) capacitor as coupling capacitor in SEPIC converter?
I found this circuit from here and have been thinking about to build it:
The author present it as Ćuk converter but I understand it as SEPIC, after reading this and this.
Q: My main concern is, ...
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1
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203
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How can I boost 1 Volts 30 Ampere input to 5V with maximum Current limit of 5A?
How can I boost 1 Volt 30 Ampere DC input to 5V DC with a maximum Current limit of 5A?
CommunityBot
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2
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1
answer
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Boost converter: doubts on signs voltages
Please, if you could explain me why on step-up (boost) converter the sign of the t-off voltage part is positive in the following equation:
Vd * tOn + (Vd - Vo) * tOff = 0
I thought that the ...
- 24.7k
0
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1
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724
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Inductor and Capacitor for Bidirectional DC-DC Converter with Battery
I have to design a bidirectional converter to regulate a DC bus at 250 V with a battery bank at 144 V. My question is how to do it optimally, because I do not know the maximum ripple allowed in the ...
- 7,581
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1
answer
2k
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LC ringing on synchronous buck converter
I am working on a board that uses LTC3891 as a buck converter to step down 24V to 12V. There is quite a significant oscillation at the switching node, upstream to the inductor which I am curious about....
- 178k
11
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5
answers
20k
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DC-DC Boost converter in Parallel
I'm trying to power a 12V 1A device with 1 cell lipo battery. At 12W, the lipo would need to provide 3.24A (assuming no power loss) to step up the voltage to 12V and providing 1A.
However the DC-DC ...
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1
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2
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1k
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Convert 3v to 5v very high amperage using boost converter
I am trying to build a power bank that has 3 output USB ports that can provide 2.1 amp each; it has 8 LiPo cells. So total of 2.1×3=6.3amps so basically 7 amps at 5.1v out.
I have built the ...
- 14.6k
2
votes
1
answer
3k
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24V to 5V converter using a LM3489
I'm currently trying to create a converter 20V-26V to 5V with an 2.1A output. So I use the LM2489 chip (datasheet: here).
My circuit is the following:
I make this circuit but with I power up ...
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-3
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1
answer
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Design of SMPS for running 10 bldc motors [closed]
I want to run 10 motors, each motor has specification of max 70 V and max current 160 amps. My doubt is, is it possible to build SMPS for these purpose. If not what would be the best alternative. I ...
- 315k
1
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2
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399
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Buck Converter 24V 12A
I'm trying to make a buck converter that should carry a load of up to 12A. Probably no surprise, the n-channel mosfet is getting hot quick, even with a heatsink it is getting to hot. (I have currently ...
- 3,807
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0
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135
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How to get uni polar sinusoidal wave from buck converter?
I am trying to build a pure sine wave inverter by using a buck converter cascaded with a square inverter. My hope is that I can vary the duty cycle in such a fashion so as to reach a fully rectified ...
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-6
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1
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95
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Boost converter is acting as a capacitor
I've just bought two Xl6009 Boost converters and both are showing the same problem. When I connect a power source to the input terminals and tried to measure their output it shows 1 on the left side ...
- 21.6k
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1
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259
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DC-DC conversion with homemade transformer [closed]
We are a group of student who are working on a project, where we want to develop an alternative type of power supply.
First some quick information about our project: We want to sent 12V DC from a ...
- 174k
-2
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1
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354
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How to drain a AA battery (9V at 2A)
I want to know if it is possible to draw 9V and 2A from a normal alkaline AA battery using a boost converter? And if not so, why is it possible then to drain batteries quicker?
CommunityBot
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2
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1k
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Mosfet keep getting short circuit
I'm in the midst of prototyping my circuit. However during testing, the psu led light keep flickering and there was no output observed. Subsequent investigation revealed that the mosfet have actually ...
- 24.5k
5
votes
4
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1k
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LM2596 and other DC-DC converters why oscillate if the output capacitor ESR value is too low?
I would like to use LM2596 converter. Datasheet says:
'If the selected capacitor's ESR is extremely low, there is a possibility of an
unstable feedback loop, resulting in an oscillation at the output.'...
3
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4
answers
11k
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Difference between synchronous and conventional dc-dc boost converter?
What is the difference between synchronous and conventional dc-dc boost converter? which one is best and why?
- 57.9k
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2
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4k
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How to design a boost converter? And how to specify the inductor and capacitor values?
I want to design a boost converter with input of 48V and need to get to a voltage of 100V.
How to select the inductor and capacitor values in it?
- 473k
1
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2
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4k
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Using a DC-DC step up converter with small solar panel
I have a small solar panel that I would like to use for charging phones or other small devices.
Goal: 5v output
The panel has an Open circuit voltage of 1.8V, Short circuit amperage is 4A. (The ...
- 294
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1
answer
517
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230VAC to 60VDC circuit
I have a (750w) psu that takes up to 60vdc and would like to plug it in a 230vac 50Hz (domestic power outlet).
There are two solutions I thought of immediately, but am not sure which one is best :
1 ...
- 17.6k
0
votes
2
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481
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Synchronous Buck High Side Driver - Why is the Fall Time of High-Side Gate Drive so Slow?
Below is the picture of my gate drive signals. The blue trace is the low side gate signal and the yellow trace is the high side gate signal. Both signals are measured across the gate and source of the ...
- 148k
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1
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2k
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I would like to use MC34063 in step up mode, but when I change the resistor value it stopped to work
I would like to use MC34063 in step up mode, to step up 19V to 24V and 1Amps current.
I made this circuit: (the values not correct its only an image from the internet)
The correct values: input 19V, ...
- 327
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2
answers
1k
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How can I add adjustable current to a DC-DC converter?
I would like to use a DC-DC converter to adjust the voltage and the current too. I would like to use MP2307, XL4015 or something similar what can easily buy.
How to add adjustable current? I dont ...
- 5,528
3
votes
2
answers
3k
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How to trim up voltage on DC-DC converter
I'm using the TVN5-2421WI DC-DC converter where I need an output of at least +/-6V (which will then go into 2 LDOs that will drop it to +/-5V), so I'm trying to use the trim pin for this, however the ...
- 73.4k
1
vote
2
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945
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2 dc-dc boost converters to create dual power supply
I'm doing a project with a Silicon Photo-multiplayer where the breakdown voltage when negatively biased is -25V. I was wondering is there anyway to connect two DC to DC boost converters to give me a ...
- 3,626
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1
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908
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What resistor values should I use with this boost DC-DC converter IC?
I'm trying to use a STOD1317BTPUR DC-DC Boost converter to drive a 12v OLED Display from a 1-cell lipo (~ 3v - 4.5v). The thing is that in the application circuit provided in the datasheet the values ...
- 13.9k
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votes
4
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759
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Can anyone explain what is doing this diode-capacitor branch on a Boost converter?
I've analized the circuit through capacitor currents to find the transfer function, but I keep getting to the exact same transfer function of the typical Boost converter, is the Diode-Capacitor branch ...
- 3,674
18
votes
3
answers
4k
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Full-bridge converter rectifier kicks
I'm in the process of building an 8kW isolated DC/DC converter, full-bridge topology.
I'm seeing some interesting phenomena on the diodes. When each diode becomes reverse-biased, a voltage spike ...
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0
votes
1
answer
737
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MP1584 EN pin voltage
The MP1584EN datasheet says: Absolute maximum ratings section: All other pin: -0.3V to 6V max. Figure 3 shows the 1.8V typical application. On the picture, there is a voltage divider: between GND and ...
- 81.4k
1
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2
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880
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MP1584 inductor calculation
I would like to calculate the inductor value for MP1584EN.The datasheet says:
$$L= \frac{V_{out}}{f_s \Delta I_L} (1- \frac{V_{out}}{V_{in}})$$
On the first page of the datasheet there is a typical ...
- 88.8k
3
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2
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8k
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How to obtain negative voltage from positive voltage ?
My question is simple. I have one power supply which generate 28 volt. I would like to obtain -18V and 18V. I don't want to voltage divider with resistor. I generated 18 V to use regulator. But I ...
CommunityBot
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2
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158
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Current in Buck Converter
In Buck Converter, when switch in ON, Vi(I/P voltage)=Vl(inductor Voltage)+Vo(O/P voltage)when we switch it On, current increases linearly(according to the wikipedia) then Vl=Ldi/dt=constant and Vo(=...
- 473k
0
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2
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127
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unknown component in datasheet
im using xl6009 dc to dc converter , in page no 7 of datasheet the sepic inverting topology is show which generates 12 and -12v .my doubt is what component is used, is it a transformer or coupled ...
- 22.6k
4
votes
1
answer
434
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What's an efficient way to get below the standard 1.25V on buck converters?
So, I purchased a buck converter which was advertised to be able to range down to 0.8V but, as you can probably guess, it only goes down to 1.25V which I understand is the reference voltage for the ...
- 473k