Questions tagged [buck]

A non-isolated DC-DC converter topology which outputs voltage less than or equal to the input voltage

Filter by
Sorted by
Tagged with
2
votes
2answers
94 views

Can I use a buck regulator for mains voltage if I put a resistor before it?

I am reverse engineering a consumer product that I have, and the circuit seems to be mains voltage (85-250VAC) -> resistor (10ohm) -> bridge rectifier -> buck regulator -> linear regulator ...
6
votes
3answers
854 views

Change voltage without consumption

Is it possible to change voltage without consuming power? I have a 5V Arduino circuit that makes use of a wireless chip (NRF24L01) that runs on 3.3V. My current approach to get 3.3V out of a 5V source ...
0
votes
0answers
57 views

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 ...
2
votes
2answers
122 views

Limiting input voltage for buck converter

I want to power some micro controllers and a couple of leds on my electric bike, counting up towards 5 Amps. Power supply is a 36V battery, with a range of about 42V to 33V. This voltage is to be ...
0
votes
0answers
41 views

Fast switching constant current buck output capacitor

I'm using a 1A constant current buck LED driver (the TPS92518 from TI), in order to implement "shunt FET dimming", where the load (1A LEDs) is short-circuited using a MOSFET in order shut-...
1
vote
1answer
71 views

Why 2 diodes in parallel buck converter design?

I have been looking up dc-dc buck converter designs and have question regarding the diodes. It says "5A High current Schottky diode" is it common in buck converter design to parallel ...
0
votes
0answers
32 views

LTC1707 Buck regulator Vout signal ground confusion

I am using the LTC1707 buck regulator to step down from ~6V (4 aa alkaline cells) to 5V. I am confused about proper grounding. Initially I used a common ground and this caused Vout to be 6V when Vin ...
0
votes
0answers
30 views

Determining Voltage Overshoot, Voltage Droop & Current Step

I have a buck converter design in excel where i am trying to determine the output capacitor using the formulas in page19 of the ADP1850. It says select the largest result of the previous three ...
0
votes
3answers
63 views

board to board soldering without castellated vias, how?

I want to produce (small scale) a simple device (0.5A stepper motor controlled by atmega and a498 with a potentiometer to regulate speed). To simplify the whole process I'm using as many ready made ...
0
votes
0answers
88 views

Low efficiency buck converter

I've seen the circuit below on YouTube. But it has low efficiency and the p-chnnel MOSFET gets hotter as the output & input voltage difference increases (it goes above 100c with heatsink). I don't ...
1
vote
2answers
147 views

Need help to understand inductor based non-isolated offline buck converter [closed]

Here ADGJ IC is used in offline buck topology. Can anyone share the schematic of it. Picture taken from sonoff mini and shelly1 board is attached below
0
votes
0answers
89 views

Buck Converter Switching Pin and Voltage Output

By using rohm's BD9G341AEFJ-LB buck switching regulator, we want to take 5V. In datasheet BD9G341AEFJ-LB's datasheet the example circuit given like But we had to try circuit that is in Image-2, ...
0
votes
0answers
54 views

High current buck converter

I am looking for a solution to step-down the 12V 82A from a server power supply to charge a 3S2P supercapacitor to 8.1V. Not sure which buck converter to go or if there are any specific limitation to ...
0
votes
1answer
37 views

High Current Buck Converter with wide input voltage [closed]

I'm currently building a powerbank with PD outputs that are capable of outputting 5 amps at 20 volts, but my battery pack is 33.6V (8S Li-ion). I've managed to find a possible buck converter IC (...
0
votes
3answers
111 views

Buck converter without inductor in a NiMH charger (Zilog AN0259 application note)

After doing some reading online, it seems that you can't really build a step-down converter with only a filtering capacitor and without an inductor, because the losses occuring during charging of the ...
1
vote
1answer
72 views

Buck Converter design, which is better? 48V->12V direct conversion or 48V->24V->12V conversion for 12V application

I am designing a 1KW DC-DC buck converter with Vin(51V battery pack with Vnom = 48V) for driving four 250W motors. Is it advisable to step down the voltage directly from 48V to 12V or should I first ...
1
vote
0answers
29 views

Peaks on buck converter voltage

I have noticed, that my +12V Buck Converter LMR16006X (Datasheet) has some voltage peaks with a constant frequency for any input voltage from +15V to +48V. This peaks are also independent of the load ...
0
votes
3answers
130 views

Is most of non-isolated power supply “safe”?

I need a large power supply (a little over 1kW) for a consumer appliance that only has a single on/off switch and some non-conductive handles. An off-the-shelf isolated supplies run at least $60 for ...
0
votes
0answers
41 views

Is it possible to connect a switching buck converter to a simple transformerless power supply?

Many cap based transformerless power supplies intended to use with 5V circuits, use a 5.6 zener diode to regulate ouput voltage. I'm using below circuit and the calculator here [which is based on the ...
2
votes
1answer
2k views

Relationship between switching frequency and controller's crossover frequency in buck SMPS

Context: tuning the control loop of a buck SMPS. I specicifally have a TI TPS40200-based circuit in mind, but I think this applies to SMPS design in general. Quoting from Type 2 compensation network: ...
0
votes
1answer
71 views

Gate driver Isolation

I have designed a 50 W, 12V-5V buck converter operating at switching frequency 200kHz.This is just for understanding practical converter circuits, so I made a totem-pole bjt driver circuit for IRF640N....
3
votes
2answers
157 views

Why is there no frequency compensation required in TI's TL494 example buck regulator design?

This example circuit is given in Texas Instrument's application note SLVA001: "Designing Switching Voltage Regulators With the TL494": They use a 140 μH inductor and a 220 μF electrolytic ...
1
vote
3answers
89 views

PSIM simulation of buck chopper

I'm having some trouble simulating a closed loop buck converter I designed.I am using PSIM for verifying the correctness of my circuit, but I can't figure out why the output is all wrong. It is ...
0
votes
1answer
159 views

Using an old eBike battery to power an electric trolling motor

I have a couple of old 36v eBike batteries lying around. I also have a Minn Kota Endura C2 30 electric trolling motor for my small boat which needs a battery. My previous experience with a large lead ...
0
votes
1answer
60 views

Optimum phase margin Controller Design

I am designing a PI voltage and current Controller (Cascaded Control for Buck Converter with LC filter) and I am confused about what is the perfect phase margin to choose for the application. I read ...
2
votes
2answers
130 views

What is wrong with my buck regulator circuit using the RY8310 IC?

A component in a larger circuit I've designed is a step-down regulator circuit. It provides an output voltage of 18V from an input of up to 29V. For no other reason than the PCB manufacturer had it ...
1
vote
1answer
64 views

Duty cycle generator (PWM Modulator)

Below is a circuit used to control duty cycle in SMPS, and I have some question about this design: Why the designer has connected the output of the error amplifier (Type 3 in this circuit) to the ...
0
votes
1answer
41 views

IC datasheet and MOSFET selection question

I am trying to design a buck converter using TI's LM3150 synchronous buck controller and I am wondering how to read some of these specs and how to select MOSFETs based on gate charge: https://www.ti....
0
votes
1answer
212 views

Shorting the Output of a voltage regulator

I am using this Buck Converter Input Voltage Range - 8-16V Output Voltage - 5V Load Current - 550mA This 5V is the power supply (Vcc) to the mentioned IC loads : Microcontroller , LED Driver , 2x CAN ...
2
votes
2answers
579 views

Two parallel CR123A batteries DC voltage converter

I selected two non rechargable CR123A lithium-manganese battery to power my project due to their ability to operate under extreme temperature. A single battery is 3V with a rated capacity of 1550mAh. ...
4
votes
2answers
865 views

Where does the inductor energy go in a buck converter when the load is suddenly disconnected?

It is known that inductors resist a change in current. So, my question is that in a buck converter, what prevents the output voltage from going all the way up due to inductor resisting a current ...
3
votes
2answers
6k views

What would happen if you connect a solar panel to a buck-boost converter?

What would happen if you connect a solar panel with the following characteristics: Max Power:3.5W Voltage: 6V Open Voltage: 7.2V To a buck-boost converter that convert an input voltage in the ...
0
votes
2answers
1k views

Making A USB Charge Cable (to replace 2.4V power supply) - Buck Converter?

I have battery-powered hair clippers that charge with a 2.4V 2000mA AC adapter. I'm looking for the best possible way to lighten or eliminate the adapter, as the one that was included is huge and ...
0
votes
2answers
104 views

Buck Converter - Ripple Current

I think I understand the buck converter operation (continuous conduction mode) except I'm a bit confused about the ripple current. Here is what I know so far I understand everything up until the last ...
1
vote
2answers
119 views

Drop input voltage for a boost converter

I have a 21V DC solar panel power source, that feeds a DC-DC boost converter. I set the output voltage of the boost converter to 19.5V to charge my laptop, but since the input voltage is higher than ...
0
votes
0answers
129 views

Buck-Boost Converter Modeling

I wanted to perform AC analysis for a buck boost converter using SIMetrix/SIMPLIS for simulation, using this simulator the designer does not need to the average model to get the frequency response of ...
0
votes
1answer
66 views

Question regarding chinese voltmeter ammeter module

I am new to this forum. I am a Diploma in Electronics from India and a passionate DIY hobbyist too. I have a question regarding cheap 10 amp ammeter and a voltmeter module I bought off aliexpress. I ...
0
votes
0answers
22 views

MOSFET Selection based on peak drain current

While selecting a MOSFET for application how do we calculate the peak currents which can occur in the circuit? I am designing a DC/DC interleaved synchronous Buck Converter (2 MOSFETS per rail) for ...
2
votes
2answers
138 views

Using a behavioral voltage source as a zero crossing detector for inductance current in LTSpice

I'm trying to simulate a buck converter IC in LTSpice (MP4569) based on the functional block diagram from the datasheet using behavioral voltage sources to represent the logic from the block diagram. ...
1
vote
2answers
54 views

Power inductor's staturation current for buck converter

Is it correct that when selecting an inductor for a buck converter I should be choosing an inductor with the saturation current higher than the converter's peak current? How much of a margin should it ...
1
vote
2answers
95 views

Understanding Buck Converters and Solar Panels

I have a solar panel rated at 5V 80mA and want to increase the output current significantly higher to around 500mA and decrease the voltage to either 3V or minimum of 2.7V, how can I go about this? I ...
2
votes
1answer
67 views

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 ...
0
votes
1answer
26 views

Determining \$I_{peak}\$ and \$f_{min}\$ and \$f_{max}\$ for MP4569 buck IC

Trying to figure out what inductance value is needed for my application of MP4569. They give the minimum inductance value in terms of \$I_{peak}\$ (page 12): \$L_{MIN}={{V_{IN(MAX)}{\times}t_{ON(MIN)}}...
2
votes
1answer
35 views

Should I avoid a switching frequency close to my target SPI or CAN frequency?

I have a kind of an open-ended question. If I'm designing a board with a buck converter and have picked out my peripherals, and say for example I want to run my CAN FD interface at 1MHz baud and maybe ...
0
votes
1answer
38 views

Voltage Mode Buck Converter Output Voltage

I am trying to design a simple buck converter. But it doesn't work as expected. Output voltage should be 19V but it is very close to input with value 48.5V. Also there is a problem with pwm generator. ...
0
votes
0answers
25 views

Constant Voltage Power Supply

I’m working on a project were I need to power to some 24V 4-20mA sensors, a 3.3V ESP32 and a 5V SIM808 module. To accomplish this I’m using a step-down buck converter to reduce a 12V electrolytic ...
0
votes
2answers
43 views

TPS54383 Thermal Pad

I'm experimenting with a TI Dual Output Buck Converter, the TPS54383. In section 11.3, on page 43, the datasheet says 11.3 PowerPAD Package The PowerPAD package provides low thermal impedance for ...
1
vote
1answer
37 views

What is the best way to tap 12v from a 6x6v battery array for intermittent loads?

Greetings beloved comrades, I recently acquired a 36v golf cart that has 6 6v batteries in series. The existing 12v accessories, mainly lights, are powered by a separate series connection to 2 of the ...
0
votes
0answers
453 views

Powering an ESP32 from a car 12V supply

I'm confused. The datasheet seems to say 3.3v, but I read (e.g., https://techexplorations.com/guides/esp32/begin/power/) that one may apply up to 12V to the 5V pin. However the car runs at about 14.5V ...
0
votes
2answers
55 views

Buck Converter has minimum output current

I was looking online for a buck converter and I came across this on eBay: https://www.ebay.co.uk/itm/DC-DC-5-40V-to-3-3V-5V-9V-12V-24V-Buck-Step-Down-Converter-Volt-Linear-Regulator/263325140035?hash=...

1 2 3
4
5
21