Questions tagged [buck-boost]
A non-isolated DC-DC converter topology
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24 views
How to improve buck converter's efficiency
I am designing a buck converter for 600 - 10V converting (60 times lower than input).
My first question - is this even possible? I've seen a 650 - 40V converter on mouser, but that is the best that I ...
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3answers
56 views
Soft latch switch circuit with buck converter load does not work
I have been experimenting with soft latch switches. There is one that EEV Blog has developed that only uses 2 NPN transistors and a P-Channel MOSFET. The circuit is seen at 14:44 in this video.
I have ...
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1answer
27 views
Can this Noise Suppression Filter/ RF Inductor be used in buck/boost converter instead?
Say I have a buck/boost converter operating at 100Mhz. Would this inductor (VAF201610FA-841-1) be a good choice if I needed larger inductance, over other fixed inductors? (considering I do not surpass ...
0
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1answer
86 views
the sound from the coil when the current is drawn
I have buck-boost converter using a TPS630250(4.2 ->Vin) - (3.3 -> Vout) in my PCB. This buck-boost converter can draw max 4A in buck mode and max 2A in boost mode.
While there is no load or ...
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3answers
68 views
Design own Buck-Boost converter - Some questions
For a project of mine I would like to design my own buck-boost converter because the fixed solutions are more expensive and a bit to big for my preferences.
Vin is 12VDC - 24VDC regulated to 12VDC ...
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33 views
LTC3115 Buck-Boost Converter isn`t able to provide specified current
Currently I am designing a regulator circuit based on an LTC3115-1 Buck-Boost regulator which should be able to supply a current of 1.5 A for charging a NiMH battery pack with 18 cells (18...28 V).
As ...
2
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1answer
67 views
Buck-Boost small signal
I read the paper "Simplified Analysis of PWM Converters Using The Model of The PWM
Switch", and I have some questions about the model of DCM (Discontinuous Conduction Mode) flyback.
This is ...
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0answers
45 views
Power output from a buck boost circuit is too low
Thanks to all who helped on the earlier part of the circuit - that's now fixed and working.
Now the buck boost circuit to drive the LED is working, but it only puts out a very small fraction of the ...
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2answers
40 views
Best practice to get several voltages from a wall adapter via buck/boost adapters
There are two battery operated devices connected to the garage door in my house. One is a bought solution which opens/closes the garage door, the other is a self-made module which detects whether or ...
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0answers
35 views
High efficiency buck-boost converters for 3.3V and 4V power rails up to 3A peak current
I need a buck-boost converter to power a 3.8-4.5V GSM module and a 3.3V controller from batteries. So I need a boost-buck converter that can give me a stable voltage over the lifetime of the batteries....
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2answers
55 views
Why is the Irms so different from Isat in different power inductors?
I'm looking at power inductors for a DC-DC boost converter clocked in the 500KHz range (but KHz could change if necessary). Here are two examples:
Example 1: Irms=55A, Isat=140A, 70nH
Example 2: ...
1
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1answer
68 views
Why do DC/DC switching controllers seem to favour the buck-boost topology over similar ones like Cuk, SEPIC and Zeta?
I am looking at various DC/DC converter topologies for a power system I am designing. The most suitable topology for me is one that can perform both step-up and step-down functions, so I am looking ...
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0answers
19 views
LTC3106 solar harvester over-voltage at output during recharge
I'm using an LTC3106 in the configuration of the attached schematic:
It works fine from battery and from Vin inputs, delivering the expected 3,3 V at Vout.
Problems arise when, with Vin present, the ...
2
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1answer
37 views
Reversible 4-switch buck-boost?
Can a 4-switch buck-boost be reversible?
The base scheme seems symmetrical but I did not find any reversible design.
Do you have an exemple of such a design?
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1answer
32 views
Transistors choice for buck boost converter using LM34936
I've been using TI's Webench online design tool for buck boost design purposes that uses LM34936.
The simplified schematic in LM324936's datasheet looks:
Webench design tool generated 4 different MOS ...
1
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1answer
60 views
How to bypass current sensor (ACS712) default 2.5V voltage output in buck/boost converter PCB
I'm having a bit of trouble coming up with the most practical fix for my buck/boost converter PCB. To give a bit of an overview, I'm using a current sensor to read the current value through an ...
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0answers
66 views
TPS61097A-33 booster providing lower voltage than input
I ve been trying to get the TPS61097A-33 working to get the promised 3.3V output voltage. I am using two AAA batteries as input and the circuit current draw is 20mA. I am using 4.7uH inductor and 10uF ...
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0answers
47 views
How does this compensation network work?
By accident I stumbled upon this Linear Technology application note (LT1074/LT1076 Design Manual):
https://www.analog.com/media/en/technical-documentation/application-notes/an44fa.pdf
Just for fun I ...
0
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1answer
46 views
1200w dc-dc boost converter low voltage protection not working
I've purchased a 1200w dc-dc converter with the model number SZ-BT07CCCV.
I'm using it to convert 12v from a big battery to 24V.
the converter comes with three potentiometers according to the ...
1
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0answers
31 views
Rule of thumb for boost converter current usage
I have a sensor that requires 12V DC for 14 seconds. I only have a 6V source. The device pulls 6.2mA at 12V during the 14 seconds. If I use a boost converter to get to 12V should I assume >12.4mA ...
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78 views
Strange oscillations in Simulink for a buck-boost converter connected to a solar panel
I am building a model of a solar power system. In it, I connect a string of solar cells to a buck-boost converter. I use Simulink and Simscape Electrical to perform simulations. I am encountering an ...
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1answer
55 views
Can I use a laminated silicon steel transformer core as a low frequency boost converter core?
Since laminated silicon steel is used in low frequency transformers, can't I also use it as an inductor in a low frequency boost converter, at maybe 100Hz, theoretically shouldn't this work as well as ...
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1answer
24 views
Using xl6009 on a 5v powerbank circuut
I want to use xl6009 boost converter on a 5v 2 amp powerbank circuit to power up my 12v amplifire amplifier load is 750ma. What you guy's think about this. Please answer my question ASAP. (sorry for ...
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0answers
48 views
Understanding type III compensation network for Buck-Boost DC/DC converter
I'm trying to design a circuit based on Linear Technology's LTC3533 Buck-Boost DC/DC Converter for my own project.
One of the last things I have left to do is to calculate the feedback loop ...
1
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1answer
48 views
Voltage drop over MOSFET controlled by microcontroller
I made the circuit below to power a microcontroller and a load from one power source.
But looking at the voltage drop between drain and source of the IRLZ44N MOSFET, instead of 12 V I got only 3.1 V ...
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0answers
34 views
Should I Boost ~3.7V to 9V and 5V or downregulate ~12.1 to 9V and 5V?
I'm restoring an old radio/cassette player and I want to add lithium-ion batteries. Originally it was able to house 6 D-cell batteries, so I thought I'll just use 3 li-ion batteries connected in ...
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1answer
108 views
I have a 5 volt converter but I also need 3.3 volts, what should I do?
Goal is to get 5V and 3.3 V output by the use of a buck/boost converter. Important is to use a converter instead of an LDO for heat reasons.
I want to draw minimum above 0.8A, preferably 1-1.2A at the ...
0
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1answer
23 views
The right way to control EN pin of TPS63806 using STM32 MCU
I have a 3.3v STM32L4 MCU powered by it's own supply and an external circuit powered by a buck-boost TPS63806. The power source is a 18650 battery, providing from 2.8-4.2 volts.
I want to turn on and ...
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1answer
75 views
Two TPS5430 inverting buck-boost converter modules failed in a row, am I using them wrong?
I've bought three of these inverting (negative voltage) DC-DC converters. I'll include hi-res images of the module's PCB at the end of my question.
Two of the three failed in a row during initial ...
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66 views
Working of -12V buck-boost supply using LM2576
I want to make a -12V supply and I came across a circuit using LM2576 that match my requirement but I am not confident enough about its working.
There is a note in the datasheet page no-16, ...
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0answers
42 views
Buck boost converter inductor rating
I am designing a buck boost converter with a 12v output, and 50A current output.
The input range is 8v-14v from a supercapacitor. However based on the Texas Instrument buck boost design sheet Basic ...
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0answers
50 views
on/off pin problems with the LM2678 5.0
PCB:
My name is Ertuğrul. I made a regulation board with an LM2678 but I have a problem: I provide 12V input but I can not get 5V output.
I only get 5V with the on/off pin enabled, but the datasheet ...
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1answer
53 views
How can I step up 6.5V to 10V?
I'm working with a buck/boost LED driver that uses a 0->10V dimmer input. I would like to use the output of an open-source LED module as a switch for the LED driver. The LED module outputs 0 V in ...
0
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1answer
38 views
Inverting Buck-Boost -12V converter Schematics
I saw two schematics for inverter switching converters for -12V output. I wonder, the first schematic uses many components compared to the second one but still, the output current rating of 2nd one is ...
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1answer
65 views
Is there a mathematical representation that represents the output voltage of a buck or boost converter in discontinuous mode?
Recently I have learned that in buck or boost converters, the output voltage depends only on the duty cycle and input voltage in continuous conduction mode or when current is continuous. However, in ...
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2answers
94 views
How does a boost converter allow for a gain in output voltage by just switching the positions of the inductor and switch?
I get that in a buck converter, a low pass LC circuit was attached and this effectively filters out high frequencies. If the bandwidth is configured so that it is lower than the switching frequency, a ...
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1answer
45 views
Generally, how do you describe the functions of the basic parts in a buck or boost converter? The parts are enumerated in the post [closed]
Here is a homework question I am answering.
1. Explain the function of the following parts in the DC-to-DC converter.
a. MOSFET
b. Schottky Diode
c. Inductor
d. Capacitor
Here is an accurate basic ...
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0answers
26 views
How does changing the inductance, capacitance and load in a buck or boost converter affect the circuit?
Before anyone calls me out, yes I am asking electronics related questions due to homework but honestly I am able to answer some of them. There are just some that I need StackExchange insights. For ...
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2answers
385 views
Why specifically use a MOSFET and Schottky diode on a buck or boost converter and not other transistors or diodes?
My electronics professor is currently teaching DC-to-DC converters. He decided to drop us some theoretical homework and just postpone the experiment. He gave us some questions. This is one of those ...
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0answers
41 views
Not able to figure out how to solve this as \$I(s)\$ is used in the feedback
I am not able to figure out the approach to this problem because \$I(s)\$ is connected to feedback instead of \$V(s)\$
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1answer
84 views
Bidirectional buck boost converter [closed]
I am searching for a bidirectional buck boost converter evaluation board for charging and discharging the batteries.
Input= upto 30V DC
Output= upto 10V to 20V DC
Current= less than 10A
I always ...
1
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1answer
51 views
How to take a nixie power supply and make a low power frequency modulated signal
The project I am working on requires a low input voltage stepped up to a high voltage at a certain frequency and PWM with low power.
I found a nixie power supply circuit that can supply 170V at 20mA ...
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51 views
Buck-boost with LT8705
I would like to do a buck-boost using H-bridge topology. I found the LT8705. I have two questions I don't understand.
How to choose the inductor of H-bridge buck-boost? The datasheet is using boost ...
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1answer
64 views
simple DCDC Step Up converter mystery
I'm designing a self sustaining guitar that has 6 amplifiers onboard and runs on a li-ion pack.
Power draw is a about 2.5A when on "full power" and I decided to make my own step up converter ...
1
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1answer
62 views
Buck-Boost polarity
One of the disadvantages of a Buck-boost converter is the minus sign at the output
(Transfer function of Vo/Vin = -D/(1-D) )
My question - Why can't we just place the load rotated? Wouldn't it solve ...
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2answers
82 views
DC-DC Boost Converter \w Inrush Current Protection - Voltage
I wanted to dive in Power Electronics and create a 24V DC-DC Boost Converter that would run from 2.5 to 5 V power supply. 80% efficiency was assumed, and 30 kHz frequency chosen for the PWM.
Initial ...
1
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1answer
123 views
Why overshoot happens in Inductor voltage in an open loop DC-DC buck converter?
I am extremely confused about why this overshoot occurs in the Inductor voltage waveform in buck converter and also why the time to achieve steady state reduces on increasing the load resistance.
...
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0answers
40 views
LTspice MOSFET stops charging capacitor past Vt
I'm building a buck-boost converter that transfers C1's charge to C2. In the schematic shown below, C1's initial charge is 4V. When I use switches instead of MOSFETs in the circuit, everything works ...
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1answer
120 views
3.7 to 5 V boost converter does not work as desired
I was trying to boost 3.7 V to 5 V @ max 1A.
Used LTC3426 DC-DC converter for it.
LTC3426 datasheet here.
I made a simulation before printing PCB and I get the voltage I needed.
However, now I have ...
1
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0answers
30 views
How is a zeta converter different from a buck-boost converter?
Both the topologies have the same output equation, but zeta appears to be better. Why's that?
