DC-DC conversion. Implies conversion of a DC voltage level up or down. DC-DC converter can be isolated or non-isolated. Electronically it can be done by many kinds of circuits, depending upon the application (charge pumps, voltage multipliers, linear voltage regulators, boost/buck switched ...

learn more… | top users | synonyms (1)

0
votes
3answers
44 views

SMPS: What is current mode instability (aka “sub-harmonic oscillation”)?

In peak current controlled switching power supplies, there is a phenomenon called “current mode instability” aka “sub-harmonic oscillation”. What is that? Can't seem to get a good explanation of ...
0
votes
1answer
37 views

Microcontroller self-shutdown with MAX682

I have read How to implement a soft power switch controllable by microcontroller? and am wondering if something similar would be possible with a MAX682. What I want, is a device that is turned on by ...
0
votes
2answers
35 views

Component selections for the ETA3406 DC/DC converter

I was browsing Seeed Studio's Open Parts Library and found the ETA3406, which is a 1.5 MHz 1.2 A Step-Down Converter. It's pretty cheap, and looks very useful for something I want to build, but the ...
0
votes
2answers
49 views

Can I use a 12V 70A source to convert/boost to 24V 5A supply?

I have a self built custom made computer that is using a Ultra X3 1000 watt power supply. Over the years I have been reducing the power needs by adopting more energy efficient hardware. My computer is ...
0
votes
1answer
69 views

Inductor calculation for DC to DC converter

How can I calculate the value and characteristics of inductor in a DC to DC converter?
0
votes
0answers
39 views

SC circuit equivalent

Can someone help me find the equivalent SC circuit for figure 3? Just like in figure 2 with its equivalent circuit in figure 1. I'm just confused with the drain of M6 connected to gate of M2 at node ...
0
votes
1answer
57 views

Convert 12VDC to 15VDC?

I have a 12V DC power supply and have a digital guitar pedal that needs 15V DC. There are a few other 9V/5V power circuits that I created using voltage regulators and a couple of capacitors, but I'm ...
0
votes
1answer
50 views

Selecting diodes for HV full bridge rectifier

I'm using a current-fed Royer self resonant circuit to generate 1kV DC output voltage. The transformer is producing a sine wave of 100kHz/2kVpp (Cap-Royer = 100nF). At the output of the transformer I ...
0
votes
0answers
46 views

Best Topology For High Voltage Isolated DC-DC converter (12V to 240v , ~0.2A)

I have been searching for a design that can serve as a basis for a supply as above, with the following design requirements. It seems most designs I can find are for low power (<10W) Flyback ...
-1
votes
3answers
200 views

DC boost converter and Ohm's Law

A circuit has a resistance of 1 Ohm, a DC power supply rated at 9W is delivering power to the circuit. Using a DC boost-converter that takes in an input of 9W can it output different voltages? Even if ...
2
votes
0answers
69 views

Optimal Capacitor Placement on DC/DC Convertor

I'm trying to decide on the best layout for caps on a DC/DC converter. Which of the following options (or another, unlisted option) is the best choice? GND Out plane with 5V Out going the opposite ...
0
votes
0answers
43 views

Cheap, easy, safe source of 100V DC at 10mA

I'm looking for a DC source to drive some little neon lamps (probably no more than 10-15 at a time). Their breakdown voltage is around 90V DC, and I would very much prefer to not mess around with line ...
1
vote
2answers
58 views

Inverting (Buck-boost) converter polarity problem

I have trouble understanding something in the circuit below. It is inverting converter, seems quite easy, but the part I don't get is when the switch is OFF we have forward-biased diode, i.e. plus on ...
0
votes
1answer
61 views

Active load using MOSFET

Good evening! I want to create an active load system where I can vary the PWM signal from the microcontroller to the control input of the MOSFET which is attached to a fixed resistive load. I want ...
0
votes
1answer
31 views

ST1S10 step-down regulator - can I drive the EN pin from the voltage divider?

The ST1S10 step-down regulator (http://www.st.com/web/en/resource/technical/document/datasheet/CD00169322.pdf) has an INHibit (active low) / ENable (high) input terminal, like any other DC-DC ...
0
votes
3answers
137 views

Boost regulator from 3V to 14V; then two LDO to make a +5/-5 power supply?

I am designing a mixed signal circuit and I need +5/-5 dual supply for my opamps. Could the following configuration work, else what are my alternatives? ...
0
votes
2answers
65 views

Best way to power sensor circuit from LiPo

I want to make small (~cigarette pack size) oscillometric blood pressure monitor (with arm cuff). The device will be powered by single cell 3.7V LiPo battery with USB charger circuit, without LCD ...
1
vote
1answer
65 views

Slow start up of LM3578

Hello all, I have this circuit which will take an input (4x1.5AA (3.5V~6.2V)) and output a boosted voltage of 12V (120mA). The problem I am facing is that the voltage takes about 10s. to build up ...
0
votes
1answer
89 views

How to make a 50V regulator?

How do I regulate the output coming from a 50V transformer? At the filter's output, the transformer has 50*1.4142=70.7 volts. But this voltage of course drops as a load is applied, since the filter ...
1
vote
3answers
110 views

Stepping down 12 V to 9 V with minimal waste of energy?

I have a 12 volt gel cell battery that outputs 13.6 volts when fully charged. I wanted to use it to provide backup power to my modem and router (both of which are supposed to draw a maximum of 0.6 A ...
1
vote
2answers
176 views

Converting 28VDC -> 14VDC at around 200A How do you pull that off with that kind of current?

Current boat has 110AC air conditioners and some small appliances but the rest of the systems are on 12VDC. Genset ate a jellyfish and has to be replaced, so I'm working out options to upgrade/change ...
0
votes
1answer
47 views

DC/DC Converter doesn't convert to 3.3V

I have a 5V DC input. I want to convert it into 3.3V DC. I'm trying to use VBT1-S5-S3.3-SMT DC/DC converter. I'm connecting my input to second pin of the converter. But it doesn't give 3.3V DC as ...
0
votes
0answers
44 views

Real world efficiency of a LM3150 Webench DC power supply design?

When designing a DC/DC step down converter with TI Webench with these parameters: Vin min: 11.4 V Vin max: 12.6 V Output : 5.0 V Iout : 8.0 A Ambient temp: 30 ºC Then turn the efficiency knob ...
0
votes
2answers
178 views

DIY 5v Solar Panels

In a nutshell : What is a good way to power a 5V project with one-two 0.5 V solar cells? The motivation is as follows: My project needs about 2.5-5 Watts from the solar panel. Also, this project ...
2
votes
6answers
817 views

Reducing voltage with resistors

I have been looking around for an easy way to convert 12v to 5v. I have seen some people saying that a simple resistor is all that is needed. ...
0
votes
2answers
61 views

LM2596 minimum input voltage question

I'm trying to feed the LM2596 (DC to DC) booster a 9V battery. Now, I see that it has a minimum voltage required of 3V. My question is this: What happens when my 9V battery drops below 3V? Would ...
1
vote
1answer
68 views

Does AMP AC/DC adapter going through a step down increase in amps per voltages (ECIG)

The latest project I'm working on is making adapter to basically use the mains for an ecig rather than usb or an battery. For anyone whos familiar with ECIGS they basically use around 3.7-6volts. It's ...
0
votes
1answer
45 views

How to regen a DC motor from the high-side of a boost converter?

I am planning to drive a 24v motor from a 12v battery, using a DC-DC boost circuit to generate the 24v and an H-bridge to PWM drive the motor. A problem arises when the motor goes into the regen ...
0
votes
4answers
157 views

Solar panel and dc motor

I want to run a 130V dc motor 2hp. I have 6 solar panel 120V dc out. I connected them in series to the motor directly and it runs, but when I check the voltage at the terminal when it is running it ...
-3
votes
1answer
92 views

How to the calculate the value of capacitor placed in series with transformer to avoid flux walking in a buck converter? [closed]

The dc value of current in primary increases(in -ve direction) as time passes, so I need a capacitor in series with transformer, but don't know what value capacitor should I use. filter capacitor = ...
1
vote
3answers
96 views

Operation of PC817

I am studying a DC-DC converter circuit design which has PC817 photocoupler in it. I am confused with the way PC817 behaves. My friend says that it is an analog photocoupler. I have tested it myself ...
1
vote
0answers
91 views

How can this isolated DC/DC converter claim a 3kv rating?

I'm referring to the Murata Power Solutions CME series DC/DC converters. Datasheet: http://www.murata-ps.com/data/power/ncl/kdc_cme.pdf If you look at the footprint of package (the -3C variant), ...
0
votes
1answer
72 views

How create a low-voltage boost (~4v to 5v)

I am looking for a circuit that will go from a Li battery that has a voltage between 3.6v and 4.3v up to 5v - and I have seen similar questions such as this and this, but those just recommend ...
1
vote
2answers
106 views

How to get 12V from 9.5-13.9V source

I have couple of lead acid battery reserved power supplies with output voltage from 9.5 (battery discharge cutoff) up to 13.9 (while charging the battery), intended for use with CCTV cameras, but ...
0
votes
1answer
99 views

Topology for a DC-DC step up converter for a single AA battery with 50V 10mA output

I need to design a very compact step up DC-DC converter for the single AA battery (input voltage 0.7-1-5V) with an output of 50V 10mA. The load should drain in a typical case about 2mA, but in certain ...
3
votes
3answers
251 views

Ways to isolate DC power source

I need to isolate my circuit from the power source of 5V dc. Since this is for medical use, and the device is powered by USB, the isolation needs to be at least 4kVrms, 5mm clearance, 8mm creapage ...
0
votes
1answer
47 views

Function of UCC2813-1 in flyback converter

I am studying a design of a fly back DC-DC converter. It is based on TL431 voltage regulator with PC817 opto-coupler. I heard that it is a popular design used. Switching PWM pulses are generated ...
0
votes
1answer
46 views

Inductances in flyback transformer

I am simulating flyback dc-dc converter in multisim software tool .. I want to know the difference betweem primary inductance and magnetising inductance , also secondary leakage inductance?
0
votes
2answers
111 views

Can I power Ardiuno using buck converter IC 3485 or any other buck circuit?

A buck circuit lowers the voltage by generating pulses at a certain duty cycle. Is it okay to give this pulsing voltage to Arduino? Can Arduino work normally with this? I have 12V battery and I want ...
0
votes
0answers
16 views

Noise in Inductor Current : Buck Converter [duplicate]

Source DC: 300v DC Output DC required : 160v DC Load Current : 7A DC Buck Converter Topology : IGBT as switch @ 8khz 1.1 mH Ferrite Core Inductor Measured Inductor Current ...
0
votes
1answer
214 views

12V DC to 220V DC Boost Converter

This is a circuit I am reviewing to generate 12V DC to 220V DC (output). At what component configuration can this circuit generate such output. The goal is to be able to at least supply 70 Watts of ...
0
votes
3answers
186 views

Spikes in Inductor Current : Buck Converter

What could be the reason of such spikes in inductor current at each Switch ON-OFF. ?? This spikes are also getting affected in load current. Please help me to reduce / remove this spikes. ( ...
0
votes
1answer
45 views

Dc Dc regulator malfunction

I am using the BD9C401EFJ chip for stepping 8.5V to 5V. The system is as stated - 1) I am supplying 8.5V from a bench power supply -> (to) BD9C401EFJ -> (output) 5V ->FT440G (another dc dc regulator) ...
0
votes
1answer
75 views

PWM Dimming results in input ripple due to excessive inrush current

I use a constant current SEPIC boost regulator ([TI LM3410X) to run a 8.5V 400mA OLED panel from a single Cell Lithium polymer battery. I have noticed that the input voltage ripple is too much (~1V ...
2
votes
2answers
119 views

Using Li-Ion battery while charging

I'm trying to design a custom intelligent electronic cigarette battery, but I'm more of a programming guy. I know basic electronics, but I need some help with the details. I've sketched up an outline ...
0
votes
0answers
80 views

Poor output efficiency of SEPIC supercap driver

I'm attempting to drive a high power led (3.6V, 700mA, nominal power 3W) from a 5.4V 3F supercapacitor via a SEPIC (see this question). While I don't have any strict design requirements, a running ...
1
vote
2answers
66 views

Problem with stepup BOOST converter

I'm using LM3478 converter to convert 12V to 30V in standard circuit for 456kHz. Circuit was working perfectly but when I was measuring something I demaged probably LM3478. I replaced it with new IC ...
1
vote
4answers
275 views

How to drop 240V DC to 5V DC

I would like to drop a 240V DC voltage to a 5V DC voltage to supply electronic. The 5V stage needs less than 5mA in current. The solutions I looked at are: Resistor divider (Not really ...
0
votes
2answers
78 views

How to theoretically determine ESR of a capacitor and DCR of an inductor for a buck converter?

How can we determine ESR of the capacitor and DCR of inductor theoretically in the design of buck converter, without using an LCR meter?
1
vote
3answers
175 views

D.C volt regulator

Summary: I have a solar panel whose output is intended for use with a 12V system. The actual output voltage under light load or no load rises to nearly 20V in bright sunlight. I wish to obtain ...