12v to 5v how do i do this
hey i need to know how to change a 12v powewr source into a 5v power source please help
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Mar 20, 2012. 2:58 PMkf8zr
says:
Is there a way to make a supply that generates 9 volts from a 5 volt source?
Example:
USB 5 volts that provides 9 volts from the output of the circuit?
I wouldn't need high current not more than half an amp
Example:
USB 5 volts that provides 9 volts from the output of the circuit?
I wouldn't need high current not more than half an amp
Nov 30, 2011. 9:28 AMnshafiq
says:
do guys have any idea to step down 9V to 5V output with 1A output current..
secondly,i'm in a process building obstacles avoidance robot with multiple sensor, do you guys have any command to to be install in PIC fro my robot...
secondly,i'm in a process building obstacles avoidance robot with multiple sensor, do you guys have any command to to be install in PIC fro my robot...
Research a simple Zener diode which is just a basic voltage regulator. This should be very easy to step down from 12V to 5V. As simple as it is I can't remember if you want a 7vdc Zener (meaning that it will drop 7 volts from whatever the input is) or perhaps you want a 5Vdc Zener (meaning that this is the output at which this particular diode will output. Sorry that my memory is failing me now.
Jan 24, 2012. 2:08 AMnanethinbentor
says:
Best Solution i have;
Buy one 12 volt car lighter charger that has 5volt out put 1AMP output
Wire it all up the tip is the +
and the neck part is the negative
Note of the polarity or you'll break the car charger
WORKS FOR ME ALL THE TIME
Buy one 12 volt car lighter charger that has 5volt out put 1AMP output
Wire it all up the tip is the +
and the neck part is the negative
Note of the polarity or you'll break the car charger
WORKS FOR ME ALL THE TIME
I just responded to your private message, but let everyone know: I actually have a couple very large crazy-looking metal resistors used in military jeeps for kicking down the voltage from 12 to 6 volts. With that said, you aren't going to want to use resistors to do that. You need a 5V regulator. The most common 5V voltage regulator is the 7805. Essentially the plus wire from the 12V input will be connect to one pin (usually the left) and the plus wire from the 5V output will be connected to another pin (usually the right) and both voltage supplies will share a ground pin (usually the middle but you are going to want to check the pin diagram for the specific 7805 you buy since it can differ... with tragic results).
No, but there should be a box with a metal plate in the back and three pins sticking out from the bottom. Theoretically, the left pin should be connected to the +12V and the right pin should be connected to +5V and the middle pin should be connected to ground for both power sources. There is a small chance that the wiring might be different depending on the manufacturer of your 7805 voltage regulator. You can find a datasheet by going to digikey.com and typing the exact markings on your 7805 into the search field and clicking on the data sheet it brings up. If you get one at radioshack it should have a diagram on the back of the packaging.
Dec 29, 2008. 10:31 AMJuggernaut996
says:
Hi there. The LM7805 voltage regulator has 3 pins. By holding the component infront(the markings toward you)of you the pin to the left is the input. The middle pin will be connected to ground. The pin on the right will be the output i.e. +5V. Try "alldatasheets.com" for searching datasheets of components.
May 19, 2009. 1:37 AMniranj_1994
says:
This regulator will become redhot, if you use this here
Mar 10, 2007. 7:35 PMfat_strat_cat (author)
says:
so what yur saying is i plug the 12v into the right pin and it will come out the left as a 5v current
Jan 28, 2008. 5:01 AMtech-king
says:
woah. randofo, you forgot somthing: using a 7805 to lower 12 volts means the Vreg ABSOLUTLY NEEDS A HEATSINK!
Mar 10, 2007. 5:14 PMfat_strat_cat (author)
says:
also do you know witch of the four pegs on a usb are the power ones and my computer says something about usb voltage exceded how do i fix this
Jan 9, 2010. 8:14 PMlegless
says:
A USB port can suply typically about 500mA (2.5W). If you exceed this you'll get an error. It's generally not a good idea to use your USB port as a power source except for devices with low power requirements.
The red is +5V and the black is ground. As far as USB voltage exceeded, that is a bad thing to see. Either you have crossed the USB wires or you have plugged in something that generates its own electricity (which is bad to do). The USB port provides 5V DC power, so you shouldn't plug in anything with its own power source (i.e. has batteries) or that can generate electricity like a motor (unless you protect it with a diode) or bad things could happen to your computer.
Dec 15, 2009. 10:18 AMjotism
says:
Pfft mine is fine and there have been arcs from the motherboard, the ram has been cut up a bit, the hdd, was thrown about, it lacked a case, the psu had been in bits and the case for it was hanging off, the usb has been shorted more times than I can remember.......
And it lasted a whole 3 and a bit years!!!
And it lasted a whole 3 and a bit years!!!
Mar 10, 2007. 7:34 PMfat_strat_cat (author)
says:
oh how do i go about protecting it with a diode cuz im running a motor on it (a vibrating motor for a massger)
Mar 10, 2007. 8:51 PMfat_strat_cat (author)
says:
ok now where does the diode go on this crewd shmatic and did i wire it right
First off, each battery is 1.5V, so when you add them, the motor that you are powering must be rated at 3V. Therefor, you are giving 5V DC to power a 3V DC motor. This isn't good for that motor and eventually it will die. You are going to need a voltage regulator to convert 5v to 3v like this and you can get it here. It works that same way as the voltage regulator that converts 12v to 5v.
Speaking of which, what do you need the voltage regulator that converts 12v to 5v for?
Speaking of which, what do you need the voltage regulator that converts 12v to 5v for?
Mar 10, 2007. 10:27 PMfat_strat_cat (author)
says:
im making a wall adapter for my usb devices that only use power because i mighnt not have my comp and need to use something that runs on usb power such as my usb masger and some other variuos devices i have made that run on usb power
Jan 9, 2010. 8:18 PMlegless
says:
fat_strat_cat just use a powered USB 2.0 hub. It will supply the extra current needed. 110V/220V to 5V "wall adapters" are a "dime a dozen" and easy to find.
Mar 10, 2007. 10:29 PMfat_strat_cat (author)
says:
and as for the motor i think it can handle the 5v power i just need to know why it is telling me usb power exceeded and how i fix it and i will also still be lokking into
Usually the motor's voltage rating is written on it. Either way, you're going to want to put a diode in parallel with the motor (bridging +5V and ground), but turned the opposite way that electricity normally flows. The schematic on the USB Apple instructable shows correct orientation. That should help. If you need to know more about that go to google and type in "snubber diode"
Mar 16, 2007. 5:39 PMfat_strat_cat (author)
says:
allso were id ground and were is input cuz im using one of those round plug type devices on my powerr supplys
Jan 11, 2008. 3:49 AMcallmeshane
says:
To be bluntera....
Go do a basic electrical course.
And... then by the time you get the understanding, on "HOW" to actually ASK this question properly, you will have enough knowledge to be able to answer it yourself.
Here is a great website with some electrical text books that you can download.
http://www.allaboutcircuits.com/
As a hint.... the WORST way to learn anything, is to ask other people to do your thinking for you.
Go do a basic electrical course.
And... then by the time you get the understanding, on "HOW" to actually ASK this question properly, you will have enough knowledge to be able to answer it yourself.
Here is a great website with some electrical text books that you can download.
http://www.allaboutcircuits.com/
As a hint.... the WORST way to learn anything, is to ask other people to do your thinking for you.
Jan 27, 2008. 7:23 PMeggybaby
says:
What an a-hole. I bet you never ask anybody for anything then, right?
well personally i think (for your own safety ect) you shouldnt be making a power supply if you dont know how to turn a 12v current down to 5v...you should learn a bit more about basic electronics first.
Sep 24, 2007. 8:09 PMcowgomoo
says:
try building a step down transformer.
you need magnetic wire and some 1 inch pvc.
take the pvc and wrap the magnetic wire around it 200 times. this is the primary.
take a new piece and wrap the magnetic wire around it 100 times.
connect the two pipes by pvc elbows.
|-o-o-o-o-o-o-o-o-|========== - input
|-o-o-o-o------------|========== - output
this should give you six volts if built properly.
you need magnetic wire and some 1 inch pvc.
take the pvc and wrap the magnetic wire around it 200 times. this is the primary.
take a new piece and wrap the magnetic wire around it 100 times.
connect the two pipes by pvc elbows.
|-o-o-o-o-o-o-o-o-|========== - input
|-o-o-o-o------------|========== - output
this should give you six volts if built properly.
This would not work for DC power and would get mighty warm with AC power since it supplies so little inductance.
Oct 15, 2007. 6:53 PMcowgomoo
says:
yah well it would work for a while until it burns out for AC and it would be fine with a fan.
Sep 25, 2007. 2:53 PMXaneco_12
says:
If U have a DC power supply U can devide the voltage with two resistences. Mesure the resistance value of whatever U r going to connect the devider to, and then just calculate de resistance values. R1 in series with (R2 paralell with Rdevice)... the ratio between the two must be 1,4 to 1. If U want a more professional aproach U can use a step down circuit using a TL594(an IC). It is not expensive and U can goole TL594 step-down and find a bunch of design plans. Hope this helped
Mar 10, 2007. 8:45 PMphotozz
says:
Pleas don't post the same questions into multiple forums. If you do an internet (Google) search on "LM7805 circuit" you will find a few thousand hits on how to create the circuit you are looking for.
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