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

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23 views

Buck-Boost converter controller design

I am trying to design a four mode buck boost converter based on the LTC3789 controller such that I want to completely substitute all the PLL functions, clock and everything else internal to it so ...
2
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1answer
27 views

High Drain Current MOSFET vs Low Drain Current MOSFET for Synchronous Buck Converter

For a battery charging application, i have to build a synchronous buck converter (i/p voltage = 12V , o/p Voltage = 4.5V) which would be driven by a PWM signal from the micro-controller. This Buck ...
0
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1answer
59 views

High voltage AC-AC or DC-DC buck conversion

I have a schematic for an amplifier which if supplied a lower voltage will still work as a low-wattage amplifier. In the original circuit this is achieved using a 3-tap transformer: I would like to ...
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0answers
46 views

LM2596 voltage dropping

I bought a cheap LM2596 adjustable buck module from eBay and I connected it to 19V power supply and adjusted it to 5V output. The problem is that when I add load the voltage drops, which is not what ...
0
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1answer
60 views

LED array at high current or high voltage?

Is it more efficient to drive LEDs at a high current and low voltage, than a lower current and high voltage? I'm in a situation where I have to design an LED driver for a custom CoB emitter, so can ...
3
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1answer
83 views

PCB Layout and Trace Widths for Buck Converter

I am doing a PCB layout for a simple 12V DC to 5VDC buck converter. The rated output is 3A continuous 5A peak. Here are links to the schematic and first go at the pcb layout. I realize the traces are ...
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1answer
34 views

-12 Volt Buck converter

I cant seem to figure this one out. Can someone please help me design a Buck converter that can take an input of around -40v and produce -12v around 2 amps?
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2answers
83 views

Why does touching the capacitor in my buck regulator cause my micrcontroller to start executing code?

I have an AC powered microcontroller board. I use a CUI module (VSK-S15-48U) to generate 48V DC from the wall. That 48V gets bucked down to 3.3V to power a micro (atmega328-mmh) and some other ...
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2answers
51 views

Layout of doubled SW pin on buck converter IC

I'm working on a PCB for the MP2617. That IC integrates a buck converter and has two physical SW pins sandwiching the VIN pin, as shown in my tentative layout below. No other pins on the IC are ...
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3answers
89 views

PCB layout of buck converter: capacitor placement

I'm designing a PCB for an IC that includes a DC/DC buck converter (MP2617). This is my first PCB, so I've been using the following resources for the layout: 1 and 2 (PDF files, the first one is a ...
4
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1answer
50 views

Increasing 12V Rail current on power supply for mobile computing

I am building a miro-itx slimline pc for my mobile home that is powered by solar. I have selected a GPU with a rated TDP of 120 Watts and a CPU with a TDP of 53 Watts.I purchased a DC-DC buck ...
0
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1answer
28 views

What kind of driver should I implement in buck convertors

I have a couple of questions. In the diagram below, when the current falls to 0 , the NMOS is supposed to turn off. Similarly when the voltage error increase the PMOS turns off. However in the diagram ...
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1answer
48 views

Effect of load changes on buck converter

I know to some extent that the control block monitors the output and adjusts the duty cycle accordingly and the output changes with change in loading (that's why the control block is used in the first ...
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1answer
30 views

QFN VS MSOP- Which is better for thermal performance

I am having to decide between a MSOP package and a QFN package for a Buck controller that I am designing in. The Part number is LTC3603. The MSOP is called an eMSOP. I cant locate any further ...
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0answers
21 views

wireless charger coil/buck converter issues

I have a wireless charging receiver coil (output 5.6 v, 1 amp) connected to a variable buck converter. When I connect the wires, I get no output reading from the buck converter and the voltage on the ...
0
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1answer
64 views

Buck converter charge battery control output voltage

I have a buck converter charging 8 series of Li-Ion batteries ( 8 x 4.2 voltage of charging) with a source of 36 V. I am using this schematic (from here): I know that for a resistive load, the ...
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1answer
60 views

Lift the FB pin of buck regulator [closed]

I have a basic buck regulator with feedback control. \ If I open feedback pin of the regulator (example lift the FB pin), then the regulator will be damaged. Why ? Regards, Azlum
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3answers
91 views

Resistor instead of Inductor in buck regulator [closed]

In buck circuit, If I mount 0E resistor instead of inductor then what will be the problem ? And what is the use of inductor in buck regulator ? whether just for filtering ? Regards, Azlum
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1answer
30 views

Feedback in hybrid power supply

During my research of PSU I came across schematic from Linear's datasheet: 1) Whats the purpose of node which is going from output to SW pin of buck converter? 2) Is node which provides 6V ...
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0answers
117 views

problems faced in buck-boost bi-directional converter with supercapacitor

i'm making a buck-boost converter. it should have an input voltage of 75 v and produce an output of 400v when in boost mode. The 75 v is to be supplied using a supercapacitor. The mosfet used is ...
2
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0answers
72 views

Regulator design for negative voltage O/P

In my application, I am generating 7.5V from TPS5430 (Buck) regulator and to generate -5V, I am assigning inductor's one leg to input of 7905 for -5V o/p. Circuit is shown. U14 is TPS5430 and U15 is ...
1
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1answer
118 views

Buck converter Mosfet gate driver

How to turn on a buck transistor via a bootstrap circuit? In my circuit, I use a AVR microcontroller to turn on and off a buck switch. What circuit should I use here? Previously, I used optocoupler ...
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2answers
76 views

Peer Review of Buck Converter

The only limitations I can think of are: Comparator/Schmitt not gate output swing time, and Transistor switching time simulate this circuit – Schematic created using CircuitLab BTW, ...
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2answers
96 views

Help with MOSFET buck converter

I've started learning about Buck Converters, and I made a miniature one on an Arduino prototype shield. But when I turn the thing on, the voltage is stuck at 5v (the voltage input). I tried ...
0
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2answers
118 views

Available synchronous buck converter chips are bidirectional (current)?

I was going through available synchronous buck converter ICs with external PWM capability (which can be controlled with the help of a micro-controller) and i found this one for e.g. I have read in a ...
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0answers
85 views

Controlled supercapacitor charging with buck converter

I'm building a charging circuit for two supercaps (2.7V, 3000F each) in series. I've got a 12V supply and a buck converter rated to 15A, which I've set to provide 4.8V. I'm using balance resistors to ...
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2answers
113 views

Is there a DC-DC converter topology that can output positive and negative?

E.g. Is there a converter topology that can take a 12v input and convert it to -12 to +12v output with respect to GND? For the record I'd really prefer something that doesn't use rare magnetics. I ...
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2answers
875 views

Is it better to boost or buck?

I'm making a solder fume extractor from an old PC fan (4-pin PWM), driven by a mid-range PIC. The fan needs 12V @ max 0.28A for power and a 5V PWM @ max 5mA to control the RPM. So I'll be running the ...
0
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1answer
113 views

Buck converter controlled by a BJT based astable multi-vibrator with zener-based feedback?

simulate this circuit – Schematic created using CircuitLab This is my rough sketch for a buck converter controlled by a BJT based astable multi-vibrator with zener-based feedback. Before ...
0
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1answer
30 views

Why should I bother with Frequency Response calculations in a Spilt-rail buck regulator design?

I'm looking at an existing implementation a split rail step-down power supply (application report). I would like to know what's the big deal with frequency response in the reference design? I think ...
0
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3answers
64 views

The role of reference voltage in buck converters?

I asked a question here which made it quite clear that it's probably not a good start to make something that I plug directly into the mains. Instead, I've decided to build a low-voltage buck ...
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3answers
147 views

Buck converter based switching power supply?

simulate this circuit – Schematic created using CircuitLab I have designed this circuit based on a buck converter. I'm just having trouble finding out which values to plug in. I.E. C1, ...
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1answer
46 views

Summer camp project questions - bike charger

For a summer camp, I am building a bike-generator. Well I have found a few articles about that on the internet, but I have put together a list of questions and I would be really appreciated if someone ...
1
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1answer
139 views

High current Synchronous Buck Converter, MOSFET or IGBT?

I am supposed to design a synchronous buck converter (to be driven by micro controller control signals for switching purpose). The input Voltage range is 10V-15V, and output voltage range is 4V-5V but ...
1
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1answer
94 views

Sanity check my first project: to control my air conditioner with a Nest

I have a window air conditioner. It works well but is a bit old — new enough to be electronic, have a remote and a digital display, but not new enough to turn on from my phone or do anything smart ...
0
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0answers
61 views

How does Mean Well LDD range DC-DC constant current drivers handle dimming?

Mean Well LDD range DC-DC, constant current buck drivers have dimming function. 5v PWM signal allows you to dim the LEDs. Without PWM, you get the full rated current output. Now knowing anything ...
0
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1answer
29 views

Periodic Steady State voltage Buck Converter

What does Periodic Steady state mean with regard to a Buck Converter ? Does it mean the normal operation ? Also, From what I read, the net change in the capacitor voltage in the buck converter is ...
0
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1answer
53 views

Basic MOSFET question

I am using a P-Channel MOSFET to build a buck converter and change 12VDC, 2A (from a 12V battery) to 5VDC, 2A (for cell phone charging), should I use a MOSFET rated for 20V, 2A or -20V, -2A? I am new ...
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0answers
60 views

Bidirectional Current converter, discrete or IC?

I read in a post (Bi-Directional Buck Boost Converter) that for bidirectional current converters when a higher current is needed, external deiscrete FET transistors have to be used. Like one on the ...
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0answers
197 views

Arduino Controlled Buck Converter

I am building a circuit which consists of a buck converter's duty cycle being controlled by the PWM output of an Arduino. Essentially the Arduino generates the PWM signal from two inputs-the input ...
2
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2answers
371 views

How to control a buck-boost converter circuit from a microcontroller?

I'm reading about buck-boost DC-DC converters lately and one thing is still not very clear for me. Most of the converter ICs that I've seen have a feedback loop input pin. For example LTC3780 requires ...
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1answer
102 views

Buck-boost converter dropping source voltage

I have two solar panels connected in series, and I'm using them to charge a phone. Together they provide about 7 V when I connect their leads to a multimeter or a basic circuit (i.e. Resistors/etc.). ...
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0answers
24 views

Step load estimation/measurement in a complex circuit

Let's say you have input buck regulator that provides a system rail which is loaded by various other regulators (LDOs, switchers) which power CPU/Memory/RF systems etc, and direct loads (speaker ...
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1answer
97 views

How to reverse the direction of operation of the motor?

For Synchronous buck, half bridge converter, how to reverse the direction of operation of the motor? That would be great if you could explain me with the circuit diagram.
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0answers
23 views

Bidirectional buck stepdown

Does any one know if you get bidirectional buck step down modules. I have found this: ...
0
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2answers
75 views

DC to DC step-up boost converter compensation pin, what values to use?

Okay, so I decided on a DC to DC boost converter but am having some difficulty figuring out what values to use for the compensation pin capacitors and resistor. The data-sheet really does not go into ...
0
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0answers
89 views

Battery charging via Buck or LDO?

I am supposed to charge a Li-Ion battery (12V 50Ah) and then discharge it over a period of time for testing purpose to measure its efficiency. And this charging and discharging is to be done using ...
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2answers
109 views

P-type MOSFET is not turning off

I am designing a buck converter as class assignment as shown in figure. I have calculated all the value of inductor and capacitor. I am applying PWM to the input of MAX627 MOSFET driver through ...
0
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1answer
95 views

USB powered Switch Mode Li-ion Charger

I want to design a Switch Mode Li-ion charger which uses 5V as input and charges a single cell Li-ion cell. I am referring this AppNote On page 4 they have given the equation to find inductor value ...
0
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2answers
315 views

AC Power loss of inductor in a buck converter

I have a custom piece of equipment that gives a value for AC power loss (Pac) for an inductor plugged into an internal buck converter circuit. The custom equipment has an oscilloscope which is ...