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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How to model PCB parasitics
I am working on a buck converter on a PCB. I would like to run some LTSpice simulations to see the impact of the parasitic inductances and resistances of the traces and coupling capacitances.
Is there ...
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Lithium Ion Battery : Cell Array Configuration (V.batt when converting to ≤ 4[V] )
Question
I am seeking to array 6x 21700 lithium ion battery cells, leaving the option for:
1S • 6P (@ V.batt.nom = 03.7 [V], range: 02.7—04.2 [V])
2S • 3P (@ V.batt.nom = 07.4 [V], range: 05.4—08.4 [...
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Problem with the current in a multiphase buck converter
I am a student of electrical and computer engineering and am currently working on a project that involves the study of a multiphase buck converter or synchronous buck converter (2 phases, in my case).
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Synchronous buck battery charging circuit using totem pole gate driver
Background - We are trying to develop a very low cost buck (day time)/boost (night time) converter for charging LFP batteries (day time) and powering LED (night time). Due to cost impact we are trying ...
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High Current Step-Down Conversion 12V-5V/100A
I inherited two 12 V, 1200 W server power supplies a while back and I'd like to press them into service as electrolysis cell power supplies for making (per)chlorates. I need to drop the output to ~5 ...
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Buck and boost converter inductor confusion
I have seen that a boost converter uses the spikes of an inductor to step up the capacitor voltage as this spike is stored on the capacitor.
Why don't we get a similar effect in the buck converter? A ...
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LM2576 TI Simulation not working
I have used the PSPICE model of LM2576 IC from the Texas instruments but the simulation is giving me false results. I have used the exact same diagram from the datasheet but the IC is not working. I ...
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Difference OTA and op-amp
I have a question about OTA (operational transconductance amplifier). Why can an OTA can be used without negative feedback but would still be able to keep its inputs (V+, V-) close each other? I have ...
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Compensating for lack of via-in-pad for buck converter thermal design
I am designing a buck converter, based on a TI chip. Both the datasheet and an excellent document "Five steps to a great PCB layout for a step-down converter" show vias in the exposed pad, ...
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Noisy signal output from BD2320 MOSFET driver
I need help or technical solutions relating to this issue I encountered with BD2320.
I intend to use two BD2320 drivers for an interleaved buck converter. One of the channels works well, but after ...
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Modulator Small Signal Transfer Function
How is the transfer function derived from that figure?
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Zero due to ESR in buck converter
How come the equation given leads to one answer for the zero location (marked 1) whereas my intuition leads to another (marked 2)
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LC filter out of the loop if crossover frequency is below resonant frequency?
Referring to slides 78-84 of http://powersimtof.com/Downloads/PPTs/Chris%20Basso%20APEC%20seminar%202009.pdf, the RLC network rings alone and the oscillations are not due to the loop.
It is my ...
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How much current should a switching regulator consume on its own?
With your help on stack exchange, I finally finished assembling my first LM5143QRHARQ1-based buck converter! And it works! It does output 7V (well 7.03V) The only problem is that it consumes around 0....
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How do I use the TPS5403 DC-DC buck to get 3.3V output from a 5-15V input?
I am trying to use the TPS5403 (datasheet) buck converter to power an ESP32 at 3.3V from an input of 5-15V, however, I can't find enough resources online to be sure in my design.
Below, I have ...
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Buck converter - what to do with the rest of the duty cycle
I am looking into making a MPPT charge controller for some solar panels - I understand that it works on the basis of using buck converters to get the most efficient voltage to current ratio for the ...
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DC-DC variable resistor's side
I plan make DC-DC mini-PCB PCB like it. In my schematic I want regulate output voltage. Because of it I made R1 as variable resistor. In my schematic I am afraid that middle pin of variable resistor ...
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Why is there an output ripple on my LM2576? [duplicate]
I built a buck converter using the LM2576HVT-15/NOPB. I built it exactly like the recommended schematic:
The diode I am using is a 1N5822 and the inductor is a 470uH inductor with a 100uF ...
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Can a buck converter functioning in CCM have non-linear behaviour at light load currents?
I've been designing a Simulink/Simscape model of a TI buck converter launchpad (https://www.ti.com/tool/BOOSTXL-BUCKCONV) and I'm trying to have my model fit the behavior of the device.
The board can ...
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PFC Boost Converter
I have two questions regarding PFC boost Converter.
Why boost converter is preferred over buck for PFC?
What is the difference between PFC boost converter and a traditional Boost converter?
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Reverse recovery diode power loss in switching MOSFET
For designing a low side non-sync buck regulator I am looking for MOSFET(s) that can provide low overall power loss. Conditions would be 60V to 48V, 10A, 600 kHz (worst case), 1 Ohm source and 0.35 ...
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How to calculate bootstrap Resistor in MC34163 Buck configuration
I am designing a DC-DC buck converter with MC34163DWG. I try to understand what value of resistor RB must I use at the buck/step down configuration and I also have questions about the CB capacitor. ...
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Choosing capacitors for Buck Converter – How many Electrolytic, How many Ceramic?
I am working on a high-power buck converter. This converter will be powering a purely resistive load (it’s a literal resistor – a heating element).
However, I am having some issues deciding how many ...
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Is the PCB routing for this LM5143A-Q1-based buck converter right?
Thanks to your advice on StackExchange, I'm in the final stage of developing my first LM5143A-Q1-based (link to datasheet) buck converter! It may be a bit rushed as I need to prepare this for a high ...
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How to convert a {200 VDC, 3A} power supply into a {12 VDC, 50A} source?
As title states, want to convert a high-voltage, low-current DC bus to a low-voltage, high-current DC bus that's more compatible with electronics circuits. This seems to be a pretty large input for a ...
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Final design considerations for LM5143A-Q1 buck converter. Are these features needed?
After a few days of learning how to make a buck converter using the LM5143A-Q1 TI IC, it's finally becoming a reality! This is the final design, highly inspired from page 30 in the datasheet, some ...
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Shielding Buck Converter
I have a simple question, and I want to ensure that nothing unexpected happens. I'm currently working on a Raspberry Pi-based robot project with a Pi camera, and I plan to power it with a battery, ...
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Buck converter PWM generation issue
I am trying to design a buck converter without using a controller IC. Input 32-52V output 12V, 50W.
I don't know how to get the desired duty cycle from the stable 2.5V error feedback. While it is ...
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How to choose the right type and values of capacitors for LM5143A-Q1 output?
While learning and trying to make my first buck converter using the LM5143A-Q1 (datasheet link) from TI, I calculated the required capacitance at the output for the IC to be able to output 31A, which ...
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How to choose the right inductor current limit for buck converter?
While learning and trying to make my first two-phase buck converter to power some servos, I found 2 x 3.3 uH inductors are needed for an application that will draw 30A (15A each). The problem is that ...
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How to choose the right inductor for buck converter with LM5143A-Q1? (from TI)
While working on my first voltage regulator circuit I got stuck at calculating the inductor value... The IC is LM5143A-Q1 from Texas Instruments, and according to the datasheet, the formulas for ...
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How to put the LM5143A-Q1 IC in voltage adjustment mode? (From Datasheet)
I'm trying to make my first voltage regulator circuit using the LM5143A-Q1
Buck IC. The datasheet does include examples and all the values required to get the 3.3/5V fixed output, but it barely has ...
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What is the optimal method for interfacing a 12VDC or 24VDC relay using a 48VDC supply in an automotive application?
I need to interface a 12VDC or 24VDC relay into a 48VDC (nominal voltage) battery pack for switching applications in my automotive design.
Directly driving the relay coil with the 48VDC battery pack ...
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Choice of DC-DC converter feedback voltage (0.8V vs 0.736V)
I am choosing a DC-DC Buck converter for my application (AP62200 family). The part in question is offered in 2 versions - one with 0.8V FB voltage (AP62200) and one with 0.736V (AP62200T). Is there ...
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Low Side N-Channel 75V to 12V Buck Converter with feedback
I want to design a buck converter for E-bike with 75V input and 12V, 20A (240W ideal case) output to drive the other components of E-bike using n-mosfet as a low side.
I also want to use a feedback ...
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Overshoot on dc/dc converter
Any idea on what would the level of overshoot that this LDO can provide?
Would that data/information on overshoot would be provided in the datasheet? If not, how should I understand that?
I am using ...
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Modelling the PID controller for a Buck Converter from a given schematic
I followed a document to implement a PID controller for a Si MOSFET based buck converter as the traditional multistep analog PID converter was not giving any good results for some reason. The document ...
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Efficiency curve of synchronous DC-DC controller with external MOSFETs
I'm designing a 48V to 12V, 300W buck converter. I am considering using the LM5148 controller and NTMFSC004N08MC switches. I'm confused about how synchronous DC-DC controllers can list efficiency ...
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Buck Converter Gate-Source Voltage anomaly
I have a desinged a buck converter which has a high side MOSFET, and due that when simulated on ALTIUM the circuit did not work as expected without a bootstrap configuration.
Now with the bootstrap it ...
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Variable Vout of Buck Converter [duplicate]
I have been trying to understand the working of buck converter (without the use of a dedicated IC). So, I used LTspice to test a circuit on the parameters:
Vin: 100 V
Vout: 50 V
Freq.: 10 kHz
I: 5 A
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LTC7803 Buck Converter Current Mode Compensation
I wanted to design a step-down converter using the LTC7803. Goal is to have a 5V, 0-2A output with an input voltage range of 10-30V. Switching frequency is set at 1MHz. As shown in the LTSpice picture ...
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Photovoltaic cells and CC load
Hello! I am newbie in photovoltaic electronics and recently learned about MPPT.
In my project load needs constant current. Does constant ...
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Is it safe to connect buck feedback after current sense shunt resistor?
Is it safe to connect feedback voltage divider to output voltage after current sense amplifier instead of connecting it before current sense resistor? Will this connection influence regulator ...
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Choosing an appropriate gate driver for IRLZ44N high side for a buck converter
For the TL;DR folks:
Need high side NMOS gate driver IC, similar to Julian Ilett's DCOI driver but cheaper, higher switching speed and less complex;
THT highly preferred, because 1,27mm perfboard is ...
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Preventing backfeeding buck converter
I have a device powered by either USB or a single-cell NiMH, like in the diagram below. The boost converter is resistant to backfeeding, but I need to prevent backfeeding the buck converter when ...
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Buck converter/ NiMH charger circuit review
I'm going to be charging an embedded NiMH battery and I'd like to use a switching charger to minimize heat production. For various reasons, I haven't found an off-the-shelf charger IC that would work ...
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How can I replace a potentiometer with a fixed resistor on a buck converter?
I want to use a buck converter which steps down 12 V DC to 5 V constant DV output to power my custom PCB.
I came across a buck converter in market which can do it but there is potentiometer on it ...
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DC to DC voltage step down converter on PCB
I'm a beginner and I'm designing a PCB where I want to power my PCB from a 12-24 V DC car charger.
On PCB itself, I want to use 5 V and 3.3 V for different components, so for this purpose I'm trying ...
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Is it possible to include a behavioural source in an LTspice sub-circuit for use in a buck converter model?
I'm in the process of modelling a buck converter following the approach in Sam Ben-Yaakov's A unified SPICE compatible average model of PWM converters article in which he models a switched inductor ...
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Why does this multi-phase buck controller have one phase to be driven by external driver?
https://www.renesas.com/in/en/document/dst/isl62883-isl62883b-datasheet
"The ISL62883 uses two integrated gate drivers and an external gate driver to provide a complete solution"
Why would ...
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