Author Topic: Boost converter (Read 18930 times)

Pavle · « **on:** February 15, 2016, 12:26:40 am »

How to make boost converter that will convert 3.8 volts to 5 volts for my android?

Audioguru · « **Reply #1 on:** February 15, 2016, 12:33:34 am »

3.8V is close to the average discharging voltage of a single Lithium ion battery cell that is 4.2V when fully charged then slowly discharges to 3.2V when it should have its load disconnected.
5V is the input to a charger circuit in a cell phone.

Do you want to make your own "power bank" that has a Lithium battery cell, a charger for it that charges from USB and a voltage boost converter circuit that regulates its output to 5V?

Pavle · « **Reply #2 on:** February 15, 2016, 12:35:15 am »

I want want to make converter that will supply micro usb port when I connect OTG devices.

han · « **Reply #3 on:** February 15, 2016, 12:58:28 am »

Why make if you can buy cheap USB power bank and get the circuit inside?? I can get one less the $1.5

michaeliv · « **Reply #4 on:** February 15, 2016, 01:39:15 am »

Here is a converter for 45c shipped: http://www.aliexpress.com/item/0-9V-5V-to-5V-600MA-USB-Output-charger-step-up-Power-Module-Mini-DC-DC/32551686634.html
Not sure what you are trying to do. If you want to supply power to the OTG slave, this will most likely work. If you're trying to charge / power the OTG host then it will likely not work. It might work with a special cable. 1st reply here: http://forums.androidcentral.com/samsung-galaxy-note-10-1-2014/429487-otg-cable-supports-charging-same-time.html

Pavle · « **Reply #5 on:** February 15, 2016, 07:16:26 am »

I want to put converter inside my android.

michaeliv · « **Reply #6 on:** February 15, 2016, 08:39:37 am »

If you mean your android phone, then it should provide power by default to OTG devices ( if it supports OTG ). If not, then please stop making humanoid robots, they will destroy humanity.

Pavle · « **Reply #7 on:** February 15, 2016, 09:05:25 am »

My android supports OTG but it cannot provide power to micro usb port.

michaeliv · « **Reply #8 on:** February 15, 2016, 10:31:49 am »

Well I can't imagine why a manufacturer would design a phone that would support OTG but does not supply any power. What phone model is it ?
Theoretically all you have to do is connect the boost converter I linked to the internal battery, power the OTG device from the output of the boost converter, connect the data lines from the USB of OTG device to the phone and it should work.
Theoretically you might also damage your phone doing this. If you're willing to risk it, let us know how it will turn out.

Pavle · « **Reply #9 on:** February 15, 2016, 12:53:58 pm »

Samsung Galaxy S3 Neo.How to makeconverter?

?

KL27x · « **Reply #10 on:** February 15, 2016, 08:44:50 pm »

You can buy DC-DC converters that are already built, or salvage them from "Minty Boost" devices.

If you want to incorporate one into your own pcb, you could of course design your own. Or you can buy pre-built DC converters that come on a tiny footprint of PCB, and there are pads that you have to oven mount to your own PCB. Or you can choose from hundreds of dedicated IC's to drive a DC boost converter, providing your own pcb layout and components to finish the circuit, minimally needing an inductor, rectifier diode, input/output caps, and the feedback resistors.

I doubt you can find room to fit a DC converter into a modern smart phone, though. So unless you are ok with gluing it to the outside of the phone, I think you might be disappointed.

Take a look at some of the IC's available. If you look at the datasheet, you will find out the parts you need. If you were going to build your own from scratch, you would minimally need the same parts plus a FET to switch, plus say a microcontroller with a comparator or ADC to get feedback and to control the switching?
http://www.mouser.com/Semiconductors/Integrated-Circuits-ICs/Power-Management-ICs/Voltage-Regulators-Switching-Regulators/_/N-6j76f?P=1z0vndw&Ns=Pricing|0

Mr Smiley · « **Reply #11 on:** February 15, 2016, 08:53:19 pm »

The first thing you need to know is how much space you have to play with

Pavle · « **Reply #12 on:** February 15, 2016, 09:27:58 pm »

Inside android:
http://postimg.org/image/3xc5o7rxh/
http://postimg.org/image/5az75s1t1/
What dimensions must be???

michaeliv · « **Reply #13 on:** February 15, 2016, 10:45:13 pm »

You won't be able to fit a boost converter inside a phone.
As for how to build one if you don't want to buy one that is already built (which will end up being cheaper) -- In the MT3608's datasheet you have a schematic and descriptions on how to choose the components.
https://www.olimex.com/Products/Breadboarding/BB-PWR-3608/resources/MT3608.pdf

Pavle · « **Reply #14 on:** February 15, 2016, 10:58:23 pm »

Can you help me to find already built boost converter that will fit inside android???

KL27x · « **Reply #15 on:** February 15, 2016, 11:08:54 pm »

michaeliv linked a very inexpensive converter in reply #4, if you can wait out the shipping.

If you have the equipment and ~~skill~~patience to deadbug something like this, perhaps you might be interested:

http://www.mouser.com/ds/2/281/LXDC44A_Series_datasheet_J-466535.pdf

rx8pilot · « **Reply #16 on:** February 15, 2016, 11:21:13 pm »

Quote from: Pavle on February 15, 2016, 12:26:40 am

How to make boost converter that will convert 3.8 volts to 5 volts for my android?

Not to be a total jack-ass, but a question that is so generic and broad is not going to encourage those that can answer it. Do some work on your own - at least frame the question with enough detail to make it look like you are trying.

You are asking for people to provide you with a FREE service. To me it sounds like you just want someone to hand you the answer without any effort - so I will not bother typing up anything.

What have you done already?
What is your background?
How much money do you want to spend?
Is this just for fun?
What android device will it go in?
etc.....etc....etc.......

Pavle · « **Reply #17 on:** February 16, 2016, 08:40:58 am »

I was trying to find but I cannot find converter that will fit inside android.

Pavle · « **Reply #18 on:** February 16, 2016, 02:57:16 pm »

Where can I find built converter that fill fit inside android?

Skimask · « **Reply #19 on:** February 16, 2016, 03:02:03 pm »

ali6x944 · « **Reply #20 on:** February 16, 2016, 04:16:44 pm »

well, could u post some values for the space u have when u assemble it all together?
because from the photos u posted the only place were there is no chips or shields is the side strip of the PCB...
u would not solder the converter in there, the converter would just slide there and be wigged between the PCB and the LCD.
i was thinking in the lines of charge pump instead of a boost but I'm not sure if it will delver enough current, or syncrones boost for high efficincy but not sure if it will fit...
see this and say what might work for u:
http://www.digikey.com/product-detail/en/LM27313XMF%2FNOPB/LM27313XMF%2FNOPBCT-ND/1590175

Pavle · « **Reply #21 on:** February 16, 2016, 05:44:55 pm »

Do you mean this side of pcb:
http://postimg.org/image/4tkiriy6f/

ali6x944 · « **Reply #22 on:** February 16, 2016, 07:39:04 pm »

yep, that's it....

Pavle · « **Reply #23 on:** February 16, 2016, 08:43:40 pm »

Free space:
Width:8mm
Length:20mm

AmmoJammo · « **Reply #24 on:** February 16, 2016, 09:03:16 pm »

I don't know of any device that doesn't output 5volts when using an OTG cable.

Both my Galaxy S6 and S5 do it, and as far as I can recall, so did the S2 I used to have.

Thats the whole point of it...


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Author Topic: Boost converter (Read 18930 times)

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