Forums Search for: Power Supply
How to get 1.5 volts out of a wall-wart power supply's 3 volt output...I am new to this group I believe anyways...Nice to meet you all!
inHi, I have recently been trying to get 1.5 volts (or anything other than th= e power supply's rated 3 volts for that matter) out of a wall-wart 3...
Hi, I have recently been trying to get 1.5 volts (or anything other than th= e power supply's rated 3 volts for that matter) out of a wall-wart 3 volt p= ower supply. The wall-wart power supply is dc in output at 3 volts and even= if I connect a 300 ohm resistor in series with the wall-wart power supply = and the load (a 1.5 volt clock, old style analog clock)and when i measure t= he voltage...
Air Purifier UV Bulbs
inAre air purifier UV bulbs 120 V AC or do they need some kind of power supply? http://www.iallergy.com/product_info.php?products_id=678
Are air purifier UV bulbs 120 V AC or do they need some kind of power supply? http://www.iallergy.com/product_info.php?products_id=678
DC 17V from PC power supply?
in1. If I shorted the +5V and +12V in the molex connector, would I get +17V? What's the max. current? 2. Could I use 17V to charge a...
1. If I shorted the +5V and +12V in the molex connector, would I get +17V? What's the max. current? 2. Could I use 17V to charge a notebook battery rated 16V and 3.8A? Would it hurt the battery? -- @~@ Remain silent. Nothing from soldiers and magicians is real! / v \ Simplicity is Beauty! May the Force and farces be with you! /( _ )\ (Fedora 18 i686) Linux 3.9.6-200....
Very interesting 'scoping results
inAt least interesting to me. On the advice from members of this newsgroup I bought a 465B TEK oscilloscope. It comes in handy now and then....
At least interesting to me. On the advice from members of this newsgroup I bought a 465B TEK oscilloscope. It comes in handy now and then. Yesterday I had to replace a power supply in one of my CNC machines. The only one available in a reasonable length of time was a used one of unknown quality. I spoke to a friend of mine and he said to 'scope the thing and look for any ripple on the DC out...
Section about switching mode power supply just started
inhttp://www.cirvirlab.com/index.php/switching-mode-power-supply.html Read first...
http://www.cirvirlab.com/index.php/switching-mode-power-supply.html Read first article: http://www.cirvirlab.com/index.php/switching-mode-power-supply/129-buck-or-step-down-converter-b asics.html
Buck DC-DC converter online simulation
Online simulation of buck (step-down) DC-DC converter is ready. http://www.cirvirlab.com/simulation/smps_buck_converter_online.php Read...
Online simulation of buck (step-down) DC-DC converter is ready. http://www.cirvirlab.com/simulation/smps_buck_converter_online.php Read theory of operation: http://www.cirvirlab.com/index.php/switching-mode-power-supply/129-buck-or-step-down-converter-b asics.html
Flyback converter
Even though some authors presents flyback converter as transformer isolated boost converter, it is more closer to reality that flyback dc-dc...
Even though some authors presents flyback converter as transformer isolated boost converter, it is more closer to reality that flyback dc-dc converter can be explained as transformer isolated buck-boost converter. Read more: http://www.cirvirlab.com/index.php/switching-mode-power-supply/132-flyback-dc-dc-converter-basic s.html Also, simulate flyback converter online on http://www.cirvirl
Forward converter is actually transformer isolated buck (step down) converter.
Read more: http://www.cirvirlab.com/index.php/switching-mode-power-supply/143-forward-dc-dc-converter-basic s.html Also, simulate forward...
Read more: http://www.cirvirlab.com/index.php/switching-mode-power-supply/143-forward-dc-dc-converter-basic s.html Also, simulate forward converter online on http://www.cirvirlab.com/simulation/smps_forward_dc_dc_converter_online.php
Benchtop Power Supply Options
inHello again, It is time for me to acquire a better bench top power solution. Most of the time I will use it to power a breadboard for...
Hello again, It is time for me to acquire a better bench top power solution. Most of the time I will use it to power a breadboard for experimentation. I used a wall wart for awhile until it got super noisy, and batteries are a hassle. I was about to go for something like this: http://tinyurl.com/qexphfy And then attach something like this: http://tinyurl.com/qc5e9ma to the leads ...
Any Oldtimers Want To Play "What Is This THing ?"
inHere's one of those old things you just pick up because it's old.=20 It is a "portable test oscillator". That much is no mystery, but that's...
Here's one of those old things you just pick up because it's old.=20 It is a "portable test oscillator". That much is no mystery, but that's abo= ut it.=20 https://dl.dropboxusercontent.com/u/29948706/DSCN0398.jpg So I dig up a 90 volt power supply, actually by taking an old amp carcass a= nd connecting between the positive and negative rails. A variac got it to t= he level I wanted. I...
low-power audio amp basics
inFor some low-power audio amps, usually less than 2 Watts, I see the amplifier powered by +V...
For some low-power audio amps, usually less than 2 Watts, I see the amplifier powered by +V and ground: http://www.redcircuits.com/Page33.htm For other, usually higher-powered amplifiers, I see a +/- power supply required. http://www.redcircuits.com/Page164.htm Do the amplifiers without a +/- supply continuously provide a voltage at 1/2 V during the silent parts, to allow the speaker room ...
ATX kludge
inI will be visiting Fry's electronics or Radio Shack on Tuesday. Need to make a list of parts to use an old ATX power supply for 12V cigarette...
I will be visiting Fry's electronics or Radio Shack on Tuesday. Need to make a list of parts to use an old ATX power supply for 12V cigarette lighter projects. http://www.frys.com/product/6269850?site=sr:SEARCH:MAIN_RSLT_PG http://www.frys.com/product/1916056?site=sr:SEARCH:MAIN_RSLT_PG http://www.frys.com/product/472305?site=sr:SEARCH:MAIN_RSLT_PG http://www.frys.com/product/2860...
Current mode control
Current mode control is the fastest control method for switching mode power supply since it has to feedback loops. Read...
Current mode control is the fastest control method for switching mode power supply since it has to feedback loops. Read more: http://www.cirvirlab.com/index.php/switching-mode-power-supply/152-current-mode-control-or-curre nt-programming-regulating-scheme.html
Voltage mode control and One cycle control
inVoltage mode control is not as fast as current mode control, but it is applicable in wider load range. One cycle control if further improvement...
Voltage mode control is not as fast as current mode control, but it is applicable in wider load range. One cycle control if further improvement of voltage mode control. Read more. http://www.cirvirlab.com/index.php/switching-mode-power-supply/157-voltage-mode-control-and-one- cycle-control.html
Power factor correction circuits
Power factor correction circuits are essential part of modern household power supplies. These circuit have a feature of behaving almost as a pure...
Power factor correction circuits are essential part of modern household power supplies. These circuit have a feature of behaving almost as a pure resistive load to the power network, and obtaining DC with sine ripple on the output. Read more. http://www.cirvirlab.com/index.php/switching-mode-power-supply/164-pfc-power-factor-corrector-ci rcuit.html
Automotive relay question
inI have a 12V SPST cube relay in my junque box. The diagram molded into the relay?s housing includes a component connected in parallel with the...
I have a 12V SPST cube relay in my junque box. The diagram molded into the relay?s housing includes a component connected in parallel with the coil which looks suspiciously like a resistor. It?s not a back-emf diode: I connected the relay coil using both polarities (using a current-limited power supply) and the same current draw is measured. What is the purpose of this resistor? ...
Automotive relay question
inI have a 12V SPST cube relay in my junque box. The diagram molded into the relay?s housing includes a component connected in parallel with the...
I have a 12V SPST cube relay in my junque box. The diagram molded into the relay?s housing includes a component connected in parallel with the coil which looks suspiciously like a resistor. It?s not a back-emf diode: I connected the relay coil using both polarities (using a current-limited power supply) and the same current draw is measured. What is the purpose of this resistor? ...
Power supply current?
inI wish to buy a power supply delivering up to 500V for experiments with thermionic valves. What would be a suitable current?
I wish to buy a power supply delivering up to 500V for experiments with thermionic valves. What would be a suitable current?
Capacitor as a power supply
inThis is more of a thought experiment triggered by handling of a huge cap. Would it be possible to charge a big cap and discharge it through a load...
This is more of a thought experiment triggered by handling of a huge cap. Would it be possible to charge a big cap and discharge it through a load resistor without dropping voltage much over a significant portion of the discharge time? One way I could think of is to use a Zener followed by an emitter follower to act like a current source. However the Zener needs a load resistor and non-zero cu...
DC-DC converters basic topologies online simulations
DC-DC converters are essential power supply circuits for modern electronic equipment today. Five basic topologies are ready now for online...
DC-DC converters are essential power supply circuits for modern electronic equipment today. Five basic topologies are ready now for online simulation. Visit them on: http://www.cirvirlab.com/index.php/tutorials/168-dc-dc-converters-online-simulator.html