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

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2answers
85 views

How can I regulate a 5V battery?

I am trying to use this 5V RAVPower battery pack to drive some electronics and a high-current load: ...
0
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0answers
45 views

Bidirectional DC-DC converter, 12V - 300V, 1 kW?

What DC-DC converter topology would you recommend for a device that supports bidirectional power flow of up to 1kW with 300VDC on the high-side and 10-15VDC on the low-side? I want to use it to ...
0
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1answer
59 views

Is it possible to use buck boost converter at the same time?

I have a input source from 50mV to 4V and I want a fixed/regulated voltage of 3V. Input voltage is varying every time so in order to achieve the 3V I have to implement Buck as well as Boost converter ...
0
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1answer
51 views

Charging 2 Li-Ion Batteries via a single charger

I'm currently building a portable USB charger. It uses 2 Li-ion batteries in series connected to a USB port via a 5V regulated buck converter. While a single Li-ion battery would suffice for most ...
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2answers
143 views

How to adjust output current on a buck converter?

I 'm planing to use a zinc–carbon 9 V battery to power up: the circuit that battery belongs to BeagleBoard-xM I 'm thinking of using a breadboard, in order to power up both circuits. ...
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1answer
84 views

what are the consequences of not using a diode in a buck converter, and why a diode must be used?

what are the consequences of not using a diode in a buck converter, and why a diode must be used? which component is most likely to break down in a buck converter circuit if a diode is not used?
2
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1answer
102 views

Extracting the Most Energy From a Capacitor

I have a 5V super capacitor which I'm trying to extract the most energy from in the most efficient way possible. This capacitor is tied to the input of some regulator (which is the question of this ...
1
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0answers
55 views

Multiple stacked DC-DC converters

I am trying to minimze the output voltage ripple of a 4-layer pcb power supply and am curious as to what approach would be better. So I have 6 low voltage high amp buck converters feeding 6 chips. ...
2
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2answers
92 views

Reducing voltage for solid state relay

I have a solid state relay which wants a 1.25-2.5V "activation" input, but my output from the micro controller is 5V. Is it possible to use a zener diode for this? Or do I need a buck converter? I ...
1
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2answers
77 views

What PWM frequency to use on SMPS

Just to give a little back ground on the project - I am currently building a buck converter linked up to 2 * 250W solar panels in parallel, then use an MPPT algorithum to track the max power. I will ...
0
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1answer
57 views

Can I use constant current LED driver as input to Buck regulator?

I have an 100W constant current LED driver that I bought in error but maybe I can use it in another way. I want to use 3 buck regulators to pwm control each individual color of 90W RGB LED. Can I ...
1
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3answers
243 views

DC-DC Step-Down (buck) converter 5V 10A 50watt, not understand how to size the supply

I have a 5V 10A 50WATT DC step-down converter: http://www.powerstream.com/dc-24V-5V.htm I'm just not understanding how to size the power supply needed to drive this converter at max power. I have an ...
2
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2answers
115 views

synchronous buck ls-FET switching losses and dead time minimization

I'm designing a Synchronous buck converter. I'm having doubts regarding the following: In the rectifying period of the converter, using a Schottky diode in parallel with the low side MOSFET will ...
2
votes
1answer
75 views

buck-boost, SEPIC IC out 3.3V and min 500mA 0.1" packaging

I am building some sort of navigation device for a logisitics project in my company. The whole thing is going to be battery (6V) powered, so I'm looking for every possible way to avoid losses to heat ...
0
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3answers
76 views

How to gauge resistance on parallel circuit with step down buck regulator

I'm trying to create a circuit with two loads in parallel ( essentially piggy backing one circuit on the power supply of the other ). Circuit 1, the main circuit requires ~900ma at 12v. Circuit 2, ...
1
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3answers
113 views

Correctly wire up a Switching Regulator

I am looking to use a Texas Instruments MC33063 Buck/Boost regulator. I have never used a switching regulator before so this may be a conceptual issue. My input voltage will probably be anywhere from ...
1
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0answers
49 views

TI's bypass mode step-down converters

Texas Instruments encourages the use of the TPS62730 step-down converter with bypass mode along its RF devices. Does this mean : its noise is low enough not to affect RF ? Thus being a more ...
2
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1answer
162 views

Audible noise in DC-DC buck converter

In my design, I have a +3.3V SMPS that provides power to digital circuits (microcontroller, EEPROM, etc.). The microcontroller allows applying a 100Hz PWM signal with variable duty cycle and with an ...
4
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2answers
155 views

Can I use digital pots for my feedback resistors to a buck-boost regulator?

I'm working on a design, and this will be my first attempt at a buck-boost regulator. I need the output to be variable because my application calls for different voltages under certain conditions. ...
1
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1answer
137 views

Buck boost converter

I have noticed that some buck boost converters say "led driver", some have step down/up control and what looks like a display voltameter and ammeter, they are adjustable to 5 Amps/32v. Obviously these ...
4
votes
3answers
304 views

What is the most efficient way to power a solar computer (5V) from a 12V lead acid battery?

My project: Power a Beaglebone Black (BBB) entirely from solar energy. Obviously energy efficiency is crucial here. My setup so far: PV panel connected to a deep-cycle lead acid battery. Now I need to ...
7
votes
1answer
180 views

Maximum limit on the Buck converter inductance value

I found the minimum inductor required for a buck converter using the following formula - $$L_1 = \frac{V_{in\,max} - V_{out}}{I_o \times K_{ind}} \times \frac{V_{out}}{V_{in\,max} \times ...
1
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1answer
73 views

Low cost Buck with LDO solution [closed]

Could any one suggest low cost solution for Buck converter with builtin LDO regulator? I have 24V input voltage, and output should be 8V @500mA and 3.6V @500mA. For 8V use buck, and for 3.6V LDO ...
4
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1answer
147 views

Current measurement in a Buck Converter

We have developed a prototype of a PID-regulated Buck converter made around the AVR XMega. 6-17V at the input, 5-10 on the output, 15A current limit, 500kHz PWM switching. The issue is, how to make ...
3
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1answer
99 views

Buck Converter with resistive load

I was reading a chapter on Step down Choppers(Buck Converters). I had trouble understanding the operation of the circuit as it wasn't explained properly in the book. When I looked up on the internet , ...
1
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1answer
91 views

Regarding Transient response of a Buck converter(Quantitative analysis…)

I want to know transient response of a Buck converter. I have seen in so many occasions, like when calculating Output capacitance, datasheets consider, say in a transient event, loop will be ...
0
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2answers
87 views

Is it possible to run a Buck converter with rectified AC supply voltage?

I know that a standard Buck converter requires DC voltage as input. But if your primary input supply is a high AC voltage, it is not very easy to make a clear DC voltage out of it. For example, if I ...
1
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1answer
98 views

What kind of capacitor should I use in Buck topology if the load is a lead-acid battery?

I'm using BQ2031 to charge lead-acid batteries. BQ2031 takes battery voltage as feed back and controls the switching element according to it. Now the load is not a passive element, instead it is a ...
4
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2answers
117 views

Are Buck converters conceptually same in low/high power applications?

I am new to power supply circuits. I am studying datasheet of buck regulator LM22676 which generate 5V/3.3V dc for micro-controller supply in one of my system.The datasheet says it has a N-channel ...
1
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1answer
432 views

Building a low-power solar/wind buck-boost converter

Using a 18V(max) solar panel, I'd like to charge a 12V lead-acid battery. I'm working from the basic inverting buck-boost circuit. My main question is, being a relatively low-power circuit, can I ...
-1
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2answers
72 views

Effect of duty ratio on buck converter with battery load

Will the battery charging circuit be able to supply charging current if the duty ratio is adjusted to 0.1?
0
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1answer
279 views

Effect on output voltage for buck converter in discontinuous mode

In a dc-dc switch mode buck converter, why the output voltage is different from the desired value when the inductor current is discontinuous? How can the voltage be adjusted to the required value? ...
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2answers
151 views

Resonant Frequency of LC Circuit in Switching Converter

Why do we set resonant frequency of LC circuit in a buck converter to be less than 10% of Fsw? For example, if Fsw is 300 kHz, why should resonant frequency be around 30KHZ. I am guessing it is due to ...
9
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2answers
490 views

What is the purpose of using MOSFET instead of free-wheeling diode in Buck topology?

(Source) I usually see Buck circuit models in which a MOSFET is used instead of a free-wheeling diode. What I understand from the Buck topology is, when the upper MOSFET is off, it doesn't matter ...
-1
votes
2answers
121 views

Is something wrong with my frequency selections for a buck converter controller? [closed]

I'm designing a processor-controlled buck converter. I'm seeing some instabilities, which I suspect may be due to improper frequency selection at different points in my system. I'm trying to regulate ...
2
votes
2answers
233 views

Buck converter with op-amp, inductor issues when load changes

I'm looking at the designs for a simple buck converter which has the P mosfet, inductor, capacitor and reverse based diode. Instead of PWM, I'm trying out to use an op-amp to switch the P mosfet but ...
1
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3answers
230 views

Any qualitative analysis saying RC snubber required or not for High current Buck converters

I have a design where i am using TPS53355 from TI to generate 0.9V @ 15A from 12V(10V-14V). For this design, i want to know whether RC Snubber required or not? as far as i know, Generally in High ...
2
votes
1answer
124 views

Extending a switch mode power supply controller IC to work under higher input voltages

I have a AP6502 IC, which is a cheap DC-DC buck converter. It converts a DC voltage in the level of 4.7V-18V to a DC voltage of 0.925V-16V. I works under 2A current maximum. Example Usage of AP6502 ...
1
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1answer
154 views

Role of Capacitor when switch is open in Buck Converter?

in a buck converter, initially, when switch is closed, then capacitor charges and stores energy. But when the switch is opened, then Inductor current flows through thr free wheeling diode, but what ...
2
votes
2answers
335 views

LC Low Pass FIlter in Buck Converter

Hi In this circuit below: What role is the LC Low Pass filter playing? The switch is switching ON-OFF alternatively, at a frequency which determines the Duty cycle, and we get an average output at ...
4
votes
2answers
497 views

Step-Down DC-DC converter question

I want to use Power over Ethernet (48V, 30W best case) to power something that's going to require up to 15W at 10V. That means I need to step down the PoE voltage but step UP the max current. As I ...
3
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2answers
149 views

Buck Converter Operation Question

i have been reading about the buck converter, and have also referred to the various online resources like here. In the above circuit, as I understand, when switch closes, current starts to increase ...
4
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3answers
210 views

Step down switching regulator heating up with light loads

I built a step down switching regulator based on a Diodes AP5100 using the datasheet example circuit with this layout. The voltage is being stepped down from 15V to 12V and the AP5100 is heating up ...
1
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2answers
401 views

Is this a bidirectional buck/boost converter

I found this interesting IC on Linear Technologies site, but I don't understand if it, or its development board, can both boost input voltage to output and buck output voltage back to input. ...
2
votes
3answers
195 views

Buck regulator frequency requirements (transient response)

Looking at the frequency choices for buck regulators, is there a defined "good" range for a particular context? Looking at datasheets, manufacturers extoll the virtues of "better transient response". ...
2
votes
3answers
382 views

Convert 320VDC to 220VAC or 48VDC voltage using 220VAC (UK) UPS?

I've got access to 12 flexible Solar Panels - 320VDC each Main voltage is 220VAC (here in the UK) and also might buy an electric engine running at 48VDC. Would a 220VAC Uninterruptable Power Supply ...
4
votes
1answer
110 views

Can a synchronous regulator “chirp” in burst mode?

I'm looking at (the millions of) buck regulators available for a project where the board will be a host board for a Gumstix Dual Cortex A9. This can pull quite a bit of current at maximum so I was ...
4
votes
2answers
286 views

Switching regulator layout advice

I am planning to use a Diodes AP5100 switching regulator to go from ~22V to 12V in my circuit, which will have a max current draw of about 1A. This is my first attempt at laying out a switching power ...
4
votes
1answer
322 views

12V -> 3.3V DC step down at low current

For a project that I've been working on, I want to drive a couple of ICs and several LEDs from an ~12V supply (lead-acid battery). I think the whole thing should draw about 100mA, so I didn't really ...
7
votes
2answers
477 views

Routing a buck/boost DC/DC converter

I need some help with the layout of a power supply. I botched the first two iterations as I do not have the necessary experience, and I would like to avoid another costly run. For the sake of ...