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farahalid
Apprentece
12 Posts |
 Posted - Jan 01 2012 : 3:11:09 PM
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this multi-brand phone charger that can display the status of phone battery and can cut off the suppy.. anyone can tell me,how to make schematic circuit for this project,,,???? i use lithium ion as a cellphone,,,please help me,,,
(Edit...Move to Power Supply) |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Jan 02 2012 : 10:08:40 AM
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| Each battery has a different physical form factor and interface to the phone. Building a multi battery charger will likely cost more than buying one for $5 at the local discount store. |
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farahalid
Apprentece
12 Posts |
Posted - Jan 03 2012 : 11:09:49 AM
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how to make charger that can cut off supply when battery full?? what circuit that i can add on main circuit of charger(for example-NOKIA charger)??
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audioguru
Nobel Prize Winner
Canada
4218 Posts |
Posted - Jan 04 2012 : 1:48:07 PM
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The charging circuit for the Lithium-Ion battery in a cell phone is fairly complicated and is inside the phone. The external "charger" is simply a 5VDC power supply.
The charger circuit senses the battery voltage, limits the max charging voltage, limits the max charging current and senses the temperature of the battery with the 3rd contact on it.
The max charging current depends on the size of the battery.
The max charging voltage is accurately 4.20V.
If the battery voltage is less than 3V then the charging current is reduced.
I don't know which battery temperature reduces the charging current.
When the battery voltage reaches 4.20V then the current is monitored and the charging is disconnected when the current reduces to a few mA.
Usually a battery charger IC is used. |
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JUAN DELA CRUZ
Mad Scientist
Philippines
476 Posts |
Posted - Jan 06 2012 : 08:27:19 AM
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quote:
Originally posted by farahalid
this multi-brand phone charger that can display the status of phone battery and can cut off the suppy.. anyone can tell me,how to make schematic circuit for this project,,,???? i use lithium ion as a cellphone,,,please help me,,,
(Edit...Move to Power Supply)
Just use Universal Travel Charger.
Nowadays, cellular phones needed a 5V unregulated supply to power the Charger IC (within the mobile phone itself) to charge its battery. |
juan dela cruz
Penniless INVENTOR |
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farahalid
Apprentece
12 Posts |
Posted - Jan 08 2012 : 08:46:17 AM
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quote:
Originally posted by audioguru
The charging circuit for the Lithium-Ion battery in a cell phone is fairly complicated and is inside the phone. The external "charger" is simply a 5VDC power supply.
The charger circuit senses the battery voltage, limits the max charging voltage, limits the max charging current and senses the temperature of the battery with the 3rd contact on it.
The max charging current depends on the size of the battery.
The max charging voltage is accurately 4.20V.
If the battery voltage is less than 3V then the charging current is reduced.
I don't know which battery temperature reduces the charging current.
When the battery voltage reaches 4.20V then the current is monitored and the charging is disconnected when the current reduces to a few mA.
Usually a battery charger IC is used.
what type of battery charger IC that you mention above???
what do you mean by 3rd contact??? |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Jan 08 2012 : 10:26:53 AM
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The 3rd contact on the battery pack is used to read temperature from a thermistor inside the pack.
Google "lithium ion charging IC" for examples. There are many out there, most coming with detailed datasheets that tell you how to build a charging circuit with them. |
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farahalid
Apprentece
12 Posts |
Posted - Jan 09 2012 : 09:51:16 AM
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thank you,,,,
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farahalid
Apprentece
12 Posts |
Posted - Jan 14 2012 : 10:41:15 AM
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| how to add sound and light to battery charger??? the sound and light will ON when battery is full??? |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Jan 15 2012 : 10:40:12 AM
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| It depends on the IC used. It may have a "fully charged" output to which you could connect a transistor to drive a LED or buzzer. Or it may not, in which case you would need to make a voltage switch to turn on the LED/buzzer when the battery voltage reaches full. |
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farahalid
Apprentece
12 Posts |
Posted - Jan 27 2012 : 08:18:44 AM
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| how can i add voltage and current sensor into my charging circuit ??? |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Jan 28 2012 : 10:20:45 AM
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| The IC will include all those functions. |
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farahalid
Apprentece
12 Posts |
Posted - Feb 02 2012 : 12:15:35 PM
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| what type of IC that should i use in this circuit?? |
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farahalid
Apprentece
12 Posts |
Posted - Feb 04 2012 : 12:39:03 PM
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I am fascinated how a cell phone battery charger knows when the battery is fully charged such that it cuts off the power to prevent further charging.
If its based on sensing a particular voltage has been reached, i wonder how is that achieved?
Or is it achieved by measuring the state of charge?
Is there a simple circuit to detect a certain voltage? |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Feb 12 2012 : 10:37:54 AM
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| Have you read any of the information I pointed you to? All the datasheets explain it. These chips base charging rate on voltage, current and temperature. They have achieved full charge when the voltage is at an expected point for the temperature of the battery and current used. Li-Ion charging is well known at this point, and there's plenty of information available via the Google. |
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remosobert
New Member
USA
1 Posts |
Posted - Mar 14 2012 : 07:27:51 AM
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| Hi.., I have not found any battery chargers for the lithium ion batteries that charge one cell at a time which will charge a cell that has gone into protection mode. I think your adjustable voltage charger for lithium battery packs that can go up to higher voltages should work. You should have current limit protection and be able to set the amount of current you want to deliver to the battery, if so limit it to about 200 mA. I hope this helps, thanks. |
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battery protection mobile phone charger
