Questions tagged [buck]
A non-isolated DC-DC converter topology which outputs a voltage less than or equal to the input voltage.
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Startup transient on LMR14030-Q1 buck converter
So I'm trying to build my first buck converter for an audio project using a TI LMR14030-Q1. My first design had some acoustic noise so I changed the switching frequency, inductor, and output ...
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LM4510 Switching Converter not working
I am using a TI LM4510 converter (datasheet) to step up from 5V to 12V (adjustable). I have good input power, enabled chip, and followed datasheet, but the output voltage is actually lower than the ...
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Output voltage not stable - What is compensation with respect to DC-DC (buck converter)?
EDITS:
Input voltage range: 24V to 48V.
Changing the load current from 0.38A to 1.018A increases the mean output voltage from 12.779V to 13.26V. The supply should be producing 12.5V.
I'm using this ...
user220456
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Need help to identify this IC
I am struggling for about three days now to find the part number for U118. Tried every online database, but I still cannot figure it out. Marking is 14YN/H 891 A981.
Any ideas about which manufacturer ...
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LM3150 Webench not matching with LTSpice?
I'm trying to implement this design from Webench (5V @ 10A):
I'm using LTspice to simulate this design, but my results are bizarre, as shown here:
I have looked into this thread: TI Webench and ...
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Half-bridge circuit not working, high side running hot
As I'm a noob in this field I’m experimenting with a half bridge circuit to run a buck converter to learn about it. First I tested my circuit by putting everything together on a breadboard and it ...
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Inrush Current problem?
I have a 360W 36V Switch Mode PSU which I am using in a garden lighting system I have designed. I'm in the UK so it's running off 240V therefore can supply about 10A.
Each section of the ...
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Phase shift at half the switching frequency of a dc-dc converter
I would like to know if, regardless of the control loop used (Voltage mode control, average current mode control, peak/valley current mode control), there is always a 90-degree phase drop at FSW/2 due ...
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Power circuitry not coming up
I've created a PCB that has two buck/boost converters, the second one being connected to the output of first one. The enable pin of the second buck converter is connected to the PG pin of the first ...
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Double frequency buck converter - minimum values of smaller and larger inductances
Consider a double frequency buck converter shown below having small and large inductors operating at higher and lower switching frequencies respectively, in order to improve both the transient ...
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Output Capacitor Design for a Multiphase Buck Converter
According to this application note from Texas Instruments, in the design of the output filter for a multiphase buck converter there are basically two ways of choosing the output capacitor. The first ...
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Feasibility of my Buck Converter Design
I aim to design a simple open loop non-synchronous buck converter for a project at my college with the following specifications.
Parameter
Value
Input Voltage
10-30 V
Output Voltage
5-9 V
Output ...
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Device not working after 12V to 5V buck converter
I'm kind of upcycling an old radio with radio, Bluetooth and cast features.
The Bluetooth module and the amplifier for the speakers work with 12V so I chose a 12V power supply. It works well. When I ...
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Checking calculation of phase and gain margin in LtSpice
I am currently studying DCDC stability analysis in LtSpice. Could you please check my phase margin calculation, am I right? And how about the gain margin calculation? Is it equal to infinity in my ...
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Buck converter driver LTC4446 running too hot, too high current
I am trying to design a buck converter, but the driver LTC4446 is getting to hot with this design and the input current is also to high (130 mA), when it should be in the uA orders... Any ideas of why ...
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Is it true that power supply design is difficult when input voltage range is wider?
During power supply (buck converter) testing, I had seen the lowest efficiency values corresponding to highest input voltage. I thought if the design meets this worst case scenario, it should be ok no ...
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EMI Filter For Low Power SMPS
I've designed a 1.25W buck converter which is fed by 220VAC(85-265) and has a 5V output. Now I'm trying to design a EMI input filter for it. I don't have a PE connection so I didn't use a CM filter so ...
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Buck converter with state feedback: does changing the input voltage changes the dynamic of the converter?
Short question: in a buck converter with state feedback, do changes in the input voltage cause changes in the dynamics of the output voltage (and inductor current)?
The problem: let's say we have a ...
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EMC (radiated emission test) issue in buck converter
i am designing CV smps 12V 1A (with EMC design) post that output side i will use dc to dc buck (Vin-12V Vout-9V, 400mA) or Boost convreter (Vin- 12V VOut-36v, 100mA). which configuration will be more ...
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reverse voltage polarity protection
I'm thinking about making a reverse polarity protection for a buck converter AOZ1284, and I've found this article design-guide-pmos-mosfet-for-reverse-voltage-polarity-protection
I didn't find the ...
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Powering buck converter using charged capacitor
Is it possible to design a buck converter using a charged capacitor to get regulated voltage output? When the capacitor voltage falls below some threshold value the inductor should be able to provide ...
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Inconsistent Output Voltage in DC-DC Buck Converter
I'm trying to implement the following tps54302 DC-DC buck converter, for a 5V 3A output:
All resistor values 1% tolerance, capacitors 5% tolerance, inductor 20% tolerance.
I'm testing with a bench ...
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Stability of Buck Converter when output capacitance is variable
I am designing a buck converter for an application that has several different loads. Depending on what devices are connected, the capacitance seen at the output of the buck converter can vary ...
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NCP3420 failing in buck converter
I designed a constant current buck DC-DC super-cap charger with the NCP3420 as a dual MOSFET driver. The current is hysteresis controlled and the disable and PWM lines are pulled low on power-up.
The ...
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Any specific precautions should be taken when using 2x AA LiSOCL2 batteries in parallel?
I am working on the wireless sensor design and one of the sensor is such that it needs to be kept ON through out the operation and it takes supply of 3V and current of about 100uA, which I think is ok ...
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Advanced ATX Power Supply Modifications
I know there are multiple tutorials and questions regarding converting an ATX power supply, new or old, to a benchtop power supply for projects. I'm fully aware of how to make the basic conversion to ...
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very high current buck converter
Need to convert 40 volts to a 24 volt 2000 amp 1 second duration pulse. long duty cycle. Current must be settable from 500 to 2000 amps and time from 0.1 to 1.0 seconds. Ideas please.
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Calculation for the Boot Strap capacitor
For design of a synchronous buck converter (which would be used to charge the battery) which would be driven by Micro-controller's PWM output, i selected the IRLB8748 NMOS Power transistors (for both ...
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Suitable switching/buck regulator - Vin = 24V and Vout = 5V and max current = 0.4A
Due to a sudden change in design requirements with regards my circuit supply voltage I'm looking to change my voltage regulation on my circuit from the classic LM7805 linear voltage regulator to a ...
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Variable switching duty cycle for buck converter even if input voltage and output load is constant
I am testing a BUCK converter and observed that has a variable DC when supplied at input voltages lower than 9.5V (if input voltage is higher than 9.5V the BOOSTER stops and DC is constant). The BUCK ...
