[SOLVED] How to double the voltage of a USB laptop/PC output

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WarlordFxZ

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I want to build a mini refrigerator using a peltier TEC1-12706,and i wish the input is from a laptop usb output which is 5v, and i want to double the power/volt/amps [one of these] so i can use the peltier at max voltage from 5v usb laptop ,i've already read a lot about how a transistor works since it say it can be use as an amplifier , but i still don't know how it works as an amplifier ,i want to ask this
1.How can i double the voltage to 10v/12v, can you send me a link or the circuit design with an explanation
2.Where's the output of a transistor[amps tht already amplified]/where's the direction ,as i know current can only flow at one direction ,but as i learning transistor i think the collector is the output,
https://electronicsclub.info/images/trancurr.gif
that's an example , is led c receive the amps tht already amplified, in tht case how is that possible as i know the output is emmiter or that's only the use of transistor as a switch so it doesn't need to be amplified and the circuit only to show the emmiter output is 0 and that was really the ouptut as a switch (am i right ?)
3.Is Peltier/Peltier TEC1-12706 can be paralleled , i try to do it with a fan from 12vdc adapter, but can only turn on the peltier,though there's small voltage flowing to the fan idk the certain voltage but it's less than 3v since i know what 3v do with the fan,
why the voltage can't be the same, but if i'm paralleled the fan with the led those two is receive the same voltage,

and please if someone know the best explanation about how transistor work is?

*sorry for my bad english, thanks
 

check out this:

https://www.electroschematics.com/648/555-voltage-doubler/

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How does a transistor work

Transistor have three legs emitter,collector and base
again there are three types of circuit possible
1)common emitter
2)common base
3)common collector

all are used as per there requirement.

For very simplicity I can explain you with transistor as switch
-think as relay
-collector is given 5v
-base is open(which will work as input
-emitter is grounded(common emitter)

case 1:
base is given 0v.that means transistor is off so you will get 5v at collector

case 2:
base is given 5v:that means transistor is on so you will get 0v at collector as circuit is complete.

hence sometimes transistor also used as NOT gate

work hard,play hard!!!!!!!!!
 
Which power amount do you expect to get from a notebook USB port?

I presume that the about 2 A which will be consumed by TEC1-12706 with 5V supply already overload your notebook.
 
FvM said:
Which power amount do you expect to get from a notebook USB port?

I presume that the about 2 A which will be consumed by TEC1-12706 with 5V supply already overload your notebook.
Click to expand...
I don't really know though,i was going to find the ideal power first that's why i want to double the usb voltage, because when i'm using an adaptor to test the peltier with 12v it's very fast to get cold,but what do u mean by overload a notebook, what will happen to it ,what's the theory ?

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that's help me a lil bit understand about transistor but yes i'm not fully understand yet hehe still going to read a lot about the difference of a circuit can be made with transistor, thank you
 

What kind of notebook USB port do you have?

- standard USB 2.0
- standard USB 3.0
- USB port with charging capability
 

USB power is a POOR choice for 12V Peltier 92W device even if you boost voltage. USB is clearly for low power devices such as 1W unless special communication and/or USB3 port can get 4.5W

However, any old PC ATX can supply this from IDE or HDD plug.
 
FvM said:
What kind of notebook USB port do you have?

- standard USB 2.0
- standard USB 3.0
- USB port with charging capability
Click to expand...
just a regular notebook, but i prefered to use the USB 2.0 that's the most used right now,
i don't really know about the charging usb, but isn't all usb port deliver an electron ? , which can be used to charge

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SunnySkyguy said:
USB power is a POOR choice for 12V Peltier 92W device even if you boost voltage. USB is clearly for low power devices such as 1W unless special communication and/or USB3 port can get 4.5W

However, any old PC ATX can supply this from IDE or HDD plug.
Click to expand...

what's the best power to cold a bottle of cola,

i'll put the bottle to a box about this big


how's that can i use the peltier to make cold that entire box room,and how much time the peltier need to cold the bottle inside ?
 

Hello!

I have the impression there is some misunderstanding. Sorry if it's not the case.

You are talking about doubling the voltage of a USB supply, you are talking about
transistors for amplification, etc, and that's why I think you might be wrong.

A transistor can amplify a signal, but it cannot give you more power than you have.
For example, USB can give you up to 500 mA / 5V. This means that the highest power
you can draw from a USB connection is 2.5W, whatever you do. If you double the
voltage of your USB, even with a 100% efficiency, you will get half of the current.
There is no way to keep the current as is while elevating the voltage, or getting
more current with the same voltage.

In other words, amplification in the case of a transistor means using some power
to make a signal larger. If you start from a 10 mV signal and amplify it to 1 V, all
the difference comes from the power you give to your transistor or amplifier.

Now Peltier cells will really draw a lot of energy. If you want to signifiantly
refresh drinks, then you will need a lot of power since the Peltier efficiency
is quite poor according to my experiments.

Overload a USB port means that drawing too much current will be detected by your
computer and it will shutdown the USB power for the port you were using (and you
will get a nice warning on your screen).

Now before thinking about the time you need, you have to find a better power
source. Somebody was talking about 100 W which seems to be a fair value. There
are fridges for car. Why not simply buy one?

Dora.
 

that is,the answers that i'm looking for,i don't really understand about the power consumption, that's help me a lot thanks,
so the signal is the voltage right ?,back then i ask my friend about what oscilloscope can measure , it's can measure an amps too, so that's wrong right? the amps can't be a signal but its the voltage [i've already googling it just in case google before ask,need a clarification ]
 

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