Questions tagged [sepic]
For questions about single-ended primary-inductor converters (SEPICs), which are a type of DC/DC converter. Use with the "dc-dc-converter" tag.
59 questions
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AC-DC power supply vs 3.7 V Li-Po battery
Can someone please help me to figure out how to replicate the power you get from a 3.7v Li-Po, but from mains power?
A DC motor, powered directly with a 3.7 V Li-Po battery draws between 400 mA and 1....
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Circuit analysis for DC-DC convertor SEPIC architecture
I'm analyzing the following reference design from Texas instrument for making a variable dual output (+/-60V form 11V):
What I'm curious to know is to understand the signal waveform for the following ...
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Filter on SEPIC architecture output for making +/- 60 V from 11 V input
I'm working on a LM5155 Boost/Flyback/SEPIC controller reference design PMP40488 from TI. The goal of the design is making variable output (maximum +/- 60 V) from 11 V input. My question is related to ...
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DC-DC converter design simulation tools and Webench design tools to identify the best-suited IC and schematic
I did a research about what are the simulation tools and webench tools for major companies like AD and TI to find a effective tools for my design purpose:
For example for Analog Devices, there is the ...
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DC-DC SEPIC convertor design
In a reference design form Texas instrument for a SEPIC architecture:
I noticed there is a specific consideration for connection between HVGND and PGND for LM3488 as follows:
At the same time that ...
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DC-DC convertor-SEPIC architecture
I'm working on a SEPIC DC-DC convertor, in the reference design from Texas instrument there is MOSFECT which is derived by DR pin of the main controller (LM3488) as follows:
There is an diode (D4), ...
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LM3478 MOSFET and inductors overheating
I'm trying to design a SEPIC converter based on LM3478, with input voltage range 12-36 V, and output 24 V 2 A. I'm calculated all relevant values of components, according to "AN-1484 Designing A ...
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LTspice: SEPIC simulated output voltage does not match known output voltage
I am designing a SEPIC that meets the following criteria:
➢ Vin = 15 V-35 V
➢ Vout = 25 V
➢ Output voltage ripple 1% peak to peak
➢ Switching frequency 100 kHz
➢ Load 10 W-50 W
Calculations have been ...
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How to calculate diode forward voltage (Vd) for a MOSFET within a SEPIC?
I am in the process of selecting a MOSFET for a SEPIC. I require Vd in order to calculate the peak currents across the inductors, which are ultimately needed to calculate the MOSFET peak current, with ...
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What's causing this ringing? GaN SEPIC Converter Gate Ringing
I'm designing a SEPIC converter using a HEMT GaN from EPC (EPC2204) and a dedicated GaN driver IC (1EDN71x6U). I've been in this loop (mind the pun) trying to mitigate gate ringing, and I'm having a ...
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Not able to get enough current from buck boost (sepic) converter made using TL494
I am trying to build a buckboost converter for converting 5-40v input to 5-35V output at 3A max to use it for many purposes by usign TL494. I am using a SEPIC topology as i want a non inverting output....
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How can I achieve high efficiency in a SEPIC with AC inductor losses? Where's all my energy going and why?
I'm building an asynchronous SEPIC converter with a wide input range (10-60 V) and a 24 V 2 A output. This is based on an LM5022, and I'm trying to achieve high efficiency as its heat generation is a ...
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Is it good idea to cascade SEPIC converters to extend the input voltage range of the XL6009?
I'm currently working on designing a current controlled SEPIC converter with a wider range of input voltage for a medium sized power application which can be powered by a lithium battery.
The existing ...
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High power DC/DC step up or boost converter
From a wall power supply of 12V (I'm planning to use the PSU), I would like to boost the voltage to 22V at 9A to power some heating foil. These heating foil requires about 130W and I need at least a ...
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How to calculate components values for LM3421 in SEPIC mode
How can I calculate the components values for LM3421 in SEPIC mode?
In the LM3421 datasheet, there is not much information about SEPIC topology. (Section 9.2.9.2 is labelled "Detailed Design ...
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Meaning of these inductor dot symbols
For the following circuit from the NCV5171 datasheet:
What is the meaning of a solid dot on one inductor and an open dot on the other?
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Beginner seeking feedback on circuit design: SEPIC with adjustable voltage
I recently got very interested in electrical engineering. After watching a bunch of YouTube videos on circuit and PCB design, I figured it's finally the time to get a bit hands on. I decided to start ...
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13-48 V SEPIC - > 19.5 Vout; 0.5 A
I am trying to design a SEPIC converter with the parameters stated above and have already drawn a schematic using the LM5022 IC. I have built the system and noticed a few things:
The output voltage ...
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Ceramic output capacitor selection for ripple current (SEPIC)
I'm designing a SEPIC converter based on a wide input voltage range SMPS controller (LTC3758). The requirement is for a wide input voltage (10-60V) with a fixed output of 28V @ 1.5A. I'm trying to ...
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Confusion of the working principle of Isolated SEPIC converter
I am a bit confused about the current flowing in the magnetizing inductance L_m when the switch is off.
I am reading a book(Erickson & Maksimovic, Fundamentals of Power Electronics, 2020), ...
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Why does this SEPIC buck-boost oscillate so much?
I've made this SEPIC regulator based on this design, using a MT3608 boost regulator, which has the same oscillation (ripple) as this question:
I've made these changes:
C1=100uF, C2=470uF
R2(bottom ...
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Is a SEPIC converter truly isolated?
I have been in two separate design reviews where the SEPIC topology was rejected for an isolated < 40W application. These meetings were at 2 different companies and with different principal ...
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Calculating ripple voltage across sense resistor (SEPIC DC-DC Converter)
I am designing a SEPIC DC-DC converter based on the LT3758 (Analog Devices). In the data sheet the maximum switch ripple current percentage is calculated using the ripple voltage across the sense ...
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Coupled Inductor for DC-DC Converter ~50W
I'm designing a DC-DC Flyback or SEPIC converter, not decided yet.
The converter is used to source some power LED's.
The output voltage up to 60V and 1A with an input of 12-24V.
The switching ...
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Powering a 12 V Relay and a 3.3 V Microcontroller with one Power Supply
I'm trying to power the LN298 motor driver in order to use a 12V linear actuator. This motor driver comes with a 5V voltage regulator, so you can power a microcontroller with one power supply. The ...
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Secondry side pulse by pulse current limit
Coupled inductor SEPIC converter using UC3843.
Vin nominal = 14 V
Vout max = 30 V
Iout max = 2 A
According calculations based on many resources the MOSFET's current will be
Peak = 7.62 A
RMS = 5.3 ...
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160
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Buck converter after SEPIC converter
I have designed a SEPIC and Buck converter using the TI power designer tool, which I have individually tested, and proved to be working correctly. They are both of the non-isolated type, but when I ...
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SEPIC converter : why average secondary inductor is the output current?
I can't get the reason the why the average secondary inductor current is the output current.
Simulation confirms it's true, as well as documentation.
But I haven't found any clear explanation. Sorry ...
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Selecting capacitor for SEPIC converter
I'm looking for an advice how to select capacitors for my SEPIC converter. I have done calculations, but I haven't find Cin, Cs and Cout yet. What seems like a problem is that there are few work ...
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sepic converter using lm3478
Is it possible to make a sepic converter of 120 W using LM3478 ?
I am trying to make the circuit in TI web bench but it is not supporting over 12V 3A in LM3478.
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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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building real simulation in multisim(NI company) of dc-dc SEPIC convertor
hi I am trying to build real simulationin multisim of dc-dc SEPIC convertor how ever in my output voltage i get a lot of RIPPLE . the problem is that I get a lot of spikes in my capacitor current . ...
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SEPIC vs. ZETA feedback
When I was reading through the RECOM book of knowledge DC-DC, I found out that the SEPIC converter has more chance of having resonance feedback than the ZETA converter. They mention that the SEPIC has ...
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How to limit starting current of a SEPIC based LED driver?
I have designed a SEPIC based LED driver which gives 60 V, 350 mA constant output with a good power factor. It is connected with 220 V AC source.Then I have used full-wave rectifier.After ...
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High voltage drop over output diode sepic converter
I made a SEPIC converter please see the wiki for the scematic:
https://en.wikipedia.org/wiki/Single-ended_primary-inductor_converter
Observation:
The output is 12V 2A max. When I use a scope I see ...
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LTspice XVII problem simulating SEPIC converter
This is the second time I'm trying to simulate a SEPIC converter today. First I went with LT3959, but after hours of trying to make it work, I assumed there is something wrong with the component and ...
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TI LM3488 SEPIC, adjustable power supply down to 0 volts
I decided to make an adjustable power supply with input voltages from 3 to 6 volts (4A), and output voltages from 2 to 12 volts. But I had a thought, that as long as I'm making it, I should make it go ...
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Lossless Resistor model in PSpice?
Is it possible to make a lossless resistor model in spice? I want to test the large signal model of my DCM SEPIC converter (without linearizing it). OrCad's PSpice library doesn't seem to have it, but ...
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SEPIC vs Cuk vs Zeta Converter
My understanding is that SEPICs, Cuks, and Zeta converters all provide a stable output voltage despite an input voltage that can vary either above or below what is desired. The SEPIC and Zeta ...
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SEPIC converter capacitors calculation
I have got a SEPIC converter design see here:
http://www.linear.com/docs/27994
The calculation of the SEPIC converter starts at page 21.
For the input capacitance on page 17 they tell you need:
\$I_{...
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SEPIC converter working in BURST mode without having one
I designed a SEPIC using the LT3467 with coupled inductors. It supply 17V starting from a 12V input.
On the simulator (LTSPICE) everything works, but on the test board there is a problem.
With 70mA ...
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Sepic based charger
I have acquired a LT1512 Sepic based controller which is a controller for charging purposes.
I have followed the datasheet as much as can, read few articles on how to set it up for my purposes, ...
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Compensation Capacitor and Resistor Values
I'm currently working on a Power Electronics project which I will convert 10-28V input DC voltage to 12V DC output voltage. I've deciced to use LM3481/3488 configured as SEPIC in my project. I've ...
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Vin: 2-36, Vout: 4.2. Should I use step-up, followed by step-down, or SEPIC?
My application has a small device, which draws about a watt, and is powered through a small dynamo, backed by a battery:
The dynamo generates 33 volts at maximum speed, close to L6902's max input ...
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Low voltage DC UPS - confirm specs
I've looked at the other answers here regarding building a low voltage UPS and have come up with the following design.
Requirements: 1) At least a couple of hours of up time; 2) USB power 5V @500mA, ...
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Can I use a common mode choke as a coupled inductor in a SEPIC converter
I do not really understand the difference between common mode chokes and coupled inductors. They are both 2 coils wrap around the same core but I know they have different purposes.
I want to design a ...
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Isolated DC/DC flyback/SEPIC
As far as I understand the flyback topology, it can be used in both buck and boost converters.
What I am not sure about is: Does it also work for the case where buck-boost is needed, i.e. \$V_{\text{...
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Why does my SEPIC converter output more power at higher temperatures? What are the implications of this behavior?
I have a Pololu S18V20ALV SEPIC voltage regulator board that is wired to a high-amperage 5V USB power source on the input and a DC brushless fan on the output. The output is set to about 5.5V. ...
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LTSpice SEPIC simulation current spikes
I am designing a SEPIC power supply using the LT3758. I have simulated the circuit in LTSpice and all the waveforms are as expected except the L1 current.
Here I see massive overshoots when the MOSFET ...
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How to choose V_out resistors for LT8494 SEPIC
I am in the middle of a project where i want to use a mcu (ST32F3028U6 with DAC of 2.4V - 3.6V) to control the V_out voltage of a LT8494 SEPIC DC/DC Converter. I understand the basic operation of the ...
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