Questions tagged [dc-dc-converter]
DC-DC conversion. Implies conversion of a DC voltage level up or down. DC-DC converter can be isolated or non-isolated. Electronically it can be done by many kinds of circuits, depending upon the application (charge pumps, voltage multipliers, linear voltage regulators, boost/buck switched converters, etc)
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How does Riset work in this Boost Converter?
I'm trying to design a boost converter for a backlight which has Vf:10.6-13.6V, If:140mA
I picked AP3031, I did steps required to find component details e.g Inductor Value, Iswmax
So far I understand....
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What is the origin of the names "forward" and "quasi-resonant" converters?
I'm curious about the names of some types of converters, such as forward and quasi-resonant converters. Why are they called forward and ...
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How to make DC-DC 5V UPS circuit, power of 5V&battery 5V&UPS out 5V?
I only found 5V UPS that has a buck circuit to 3.7V li-battery(18650). Now I has a 5V li-battery that has a Cut-off voltage of 4.2V and want to make a UPS circuit as shown in the figure. Is it ...
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Voltage drop issues in LTspice simulation for buck converter using SW model
I have a LTspice design issue where I encounter the same problem, even when I use other available simulations.
Whenever I increase the load, there is a significant drop in voltage, despite having ...
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HV output flyback converter voltage spikes reduction
I'm trying to reduce the voltage spikes on the output of a high voltage output (~400 VDC). This output is used to apply a stimulus on a patient to evoke a response, so the output load depends on the ...
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What does "Single-Ended Primary Inductor" mean?
SEPIC stands for Single-Ended Primary Inductor Converter. Could anyone explain what "Single-Ended Primary Inductor" means in this context?
(Image from schematic of SEPIC in wikipedia here)
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UC3844 IC duty cycle problem [closed]
Recently I started building a flyback converter with a targeted input voltage of 12-24 V and output voltage of 150 V. The swicthing frequency is set to 100 kHz, for testing purposes I've used a ...
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What is the correct definition of a floating output DC-DC converter?
This is what Dave Tweed wrote in his post here about a floating power supply:
It simply means that the output side of the power supply is completely isolated from the input side, not even sharing a ...
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How can I control sudden drop in battery voltage while connecting a motor
I have a 12V 45AH battery connected with 800W DC motor . When I switch ON a sudden drop in battery voltage. Do I need to use some device in between
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Wide input voltage range buck/boost converter
I am designing a power supply circuit for a battery-operated device. My list of requirements:
Very low quiescent current (ideally under 1 uA), where by "quiescent" operation I mean no or ...
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Current flow from Output To Input of my Buck Converter
I just made my buck converter, this is gonna used in MPPT project. I use simple buck converter in this project.
My problem is when I connect battery to output of buck converter, then electricity is ...
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Does current mode control for dc/dc conv imply a constant current output?
I am getting very confused, I have read articles about current mode and voltage mode control, and it seems that most converters use current mode control - which seems has two nested control loops. The ...
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For a high powered LED loads, is a buck or boost converter more efficient / simpler?
I have a 3 high powered LEDs hooked up into a strip to for the load. For simplicity, I am going with a constant voltage driver. The load can be hooked up in 2 configurations:
Config 1:
3 Green LEDs (3....
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What is Ćuk converter's switch voltage stress?
I know voltage stress occurs during 1-D (switch off).
So voltage stress is going to be Vc1/(1-D).
But my professor said voltage stress is Vin + Vout because of charge balance law, but I didn't ...
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Switching Freq. and Output voltage error
Attached is the datasheet for the Synchronous Buck Controller: https://www.ti.com/lit/ds/snvsb32b/snvsb32b.pdf?ts=1711536038118&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FLM5145EVM-HD-20A
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Welding machine schematic: PWM controller connections
I don't understand why the VFB pin of the UC3845AD PWM controller is grounded, and why the compensator pin is connected to the output of the LM224 through VD1 and VD2.
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Lithium Ion Battery : Electrolytic Capacitor At Buck Converter Output
It is recommended not to parallel electrolytic capacitors with a battery due to the leakage current of the electrolytic capacitor (which is small but worthy of consideration over large time periods) ...
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Oring Diodes: is RC discharge circuit needed for prevent disconnection issue?
I have a new design implemented with oring diodes circuit as shown in picture below, where I have POE_VIN_24V coming from POE+ Module, and PHNX_DC_IN coming from phoenix connector, that is connected ...
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Is K7803-500R3 DC-DC converter "enough" for my circuit?
I have recently made a relay board powered by 12V and using a DC-DC conveter to step down to 3.3V . My question is as the title says, is the K7803-500R3 converter good enough for my board or should I ...
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Fly-buck converter common mode attenuation
I'm designing a "fly-buck" converter, as shown in the example picture below.
For coupled inductor I was planning to use one with 1 kV functional isolation voltage.
This converter needs to be ...
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How to make stable +-5V from li-po battery?
I am using LT3463 from Analog Devices to generate +-5V from li-po battery.
The ripple of DC/DC output is quite large. Then it affects back to the main power line.
Yellow is main power line (input of ...
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DC-DC Converter MOSFET Failures
I've been seeing failures in a few of my circuits in which Q17 and sometimes also Q16 are failed closed in the DC-DC converter. MOSFETs used are Vishay SiHP12N50E.
Below is a schematic reference for ...
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Buck Converter Current Mode Control Simulation
I have downloaded LTspice PWM switch from christophe basso website http://powersimtof.com/Spice.htm file name PWM-CM2-MD2 by Mark Dimattina
I am doing 5.1V converter based on LTC3890 IC so I tried to ...
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Buck Boost Charge Capacitor Balance
For a buck boost capacitor charge balance, I am curious if adding equation 11.7 and 11.10 is correct? Or is this the average inductor current?
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Current Mode Control
I am referring the doc https://www.venableinstruments.com/current-mode-control-wp and trying to understand behavior of current mode control but unable to understand following things
1.
What is the ...
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Synchronous SMPS Enabling with Charged Output
When using standard slow-start circuits that slew the 'comp' net for topologies like synchronous buck and boost converters, there can be reverse current events if the supply attempts to enable when ...
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Forward converter current flow confusion
I am slightly confused about the flow of the current in the forward converter during the turn off time of the MOSFET (when diode on left is conducting) as shown below. Now I am considering that n1=n2=...
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SIMPLIS (Elements version) - PWL Topologies Error Dialog Box = Annoying
Within the free version of SIMPLIS, there is an example "LLC_HALF_BRIDGE_CONVERTER". I can't seem to share the file, but it's free and anyone who downloads SIMPLIS has access to it. The ...
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Comparison of forward and flyback converters in terms of losses
If you read comparisons of different topologies in the context of power, you may notice that forward converters are usually recommended for higher power levels compared to flyback converters.
Could ...
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FETs in push-pull converter keep blowing
I have a push-pull converter that uses BSC040N10NS5ATMA1 MOSFETs. I have also tried using CSD19533Q5A MOSFETs.
The FETs keep blowing at low power output (about 15 W). I am trying to get to 100 W. They ...
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Average Modelling of Buck Converter
I am doing Modelling of Buck Converter for LT3890 (Datasheet link attached) for Frequency response analysis .
I have some reference model of Buck converter ,please refer below image
Datasheet Link: ...
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How can I protect a MOSFET from high voltage spikes in a DCDC converter?
I built DCDC converter using TL494 that is able to step down 30-200V to 12V with reasonable output. The circuit worked fine for quite a while, but I have always tested it while slowly raising the ...
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Powering multiple loads at same voltage with separated DC-DC converters
I'm working on the power distribution PCB of a battery powered robot with multiple loads at 24V, 12V and 5V. My idea is to use a big 24V converter, and then another two smaller converters to go from ...
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How to charge a 2200 µF capacitor to 59 V in around 100 ms from a 12 V battery?
I need to charge a 2200 µF capacitor to 59 V in around 100 ms from a 12 V battery. This converter needs to be at most 35 mm wide.
This requires the use of either a boost converter or a DC-DC flyback ...
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Could DC-DC isolated power supply switching noise harm the input of an instrumentation preamplifier?
I am looking for a noiseless protection against 100ms pulse of 1kV of an input of ultralow noise instrumentation preamplifier (eight AD8428 connected in parallel, fixed gain of 2000) to measure very ...
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Current driven proportional solenoid EMC
I'm looking to control a solenoid like this one through up to 60 feet of cable. (PV3P12032A0)
One chip I've looked at is the infineon TLE82453, although there are quite a few of this type from ...
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Cuk Converter Average Model
I would like to create average model of Cuk converter but not getting any reference. Can anyone give any reference or some idea to start with?
"Generally Cuk converter is 4th order but if we use ...
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Power Converter Average Modelling
This image is from Christophe Basso presentation. It has been mentioned in the slide that average model can predict the transient response but I have one question when we say average model then it ...
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Parallel resistors with polarised capacitor
I have been trying to choose the input capacitors for an SMPS and have noticed resistors being used in parallel with the polarized capacitors.
Since these designs are for an 800 V system, I am ...
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How to add a current limit for a dual rails power supply?
I want to make an adjustable power supply with -18 V and 18 V separately adjustable outputs. I found this circuit might be the best and simplest one to do the job.
How can I limit the output current ...
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DC/DC buck regulator regularly emits an audible clicking noise
Relevant TI forum post with no resolution: here.
I am using an AOZ2264NQI-11 chip to convert 24 V down to 12 V. I originally designed this circuit for use with an AOZ2261NQI-12 chip, which has an ...
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Buck converter frequency lowers as load current rises (TI TLV62595)
I simulated a design in the TI Webench tool and I am wondering why the switching frequency falls to 1.2 MHz @ 4 A. Like, where is the point of 2 MHz @ 1 A, when peak current and voltage ripple is the ...
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two DC-DC converters to get split rail
I'm trying to design a circuit to power my DIY analog synthesizer.
My requirements are:
9V DC input voltage (from a common 9V wall adapter)
+/-15V output voltage
able to supply about 500mA on +15V ...
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DC-DC Buck Converter high current, low quiescent current
I have an application where I'm trying to drive a 5 V 2 A load under control of a low-power microcontroller (MCU).
I was looking for a buck converter with low quiescent current for the MCU (e.g. <...
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LM27313 boost converter failure
I am trying to assemble a boost converter using the LM27313 (datasheet link), following the reference design and calculations given in the data sheet. The load is 6 white LEDs (Vf=2.95V) in series.
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Do solid state phased arrays need isolated power supplies?
Non-isolated DC/DC supplies could have higher power density but it seems that high power solid state phased arrays utilize mostly isolated DC/DC converters to power each of their amplifiers.
Why are ...
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Parallel resistor across inductor practical model - switching converter [closed]
While designing switching converter, I have included the inductor practical model as shown in the image. Since Rvar2 is small value and in the order of milli-ohm. I see it is impacting my circuit ...
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Why is there a difference between the model primary and physical primary in a forward converter, but not between the secondary or tertiary windings?
In a forward converter, the current through the physical primary winding is the sum of the current through the magnetizing inductor and the current through the model primary winding.
However, the ...
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MP28167-A DC-DC converter recommends a resistor T-network in feedback loop
I am designing a DC-DC buck-boost converter using the MP28167-A, and the datasheet contains this section:
I understand the need for a resistor divider such that the closed-loop control regulates the ...
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What is the relationship between the windings in a forward converter?
I'm trying to sketch the currents through each transformer winding of a forward converter. I also need to sketch the current through the source. I have a sketch of the current through the magnetizing ...