MobileRead Forums - View Single Post - My efforts to create a Kindle Keyboard lit cover

itakatz · 06-15-2012, 05:57 AM

The information on the battery is the total capacity, not current (therefore it is measured in mAh, which is milliamps per hour. 1920 mAh means you can get a current of 1920 mA for one hour, or 192 mA for 10 hours, etc. But it doesn't give information about the maximal current you can draw from the terminals without damaging the device. Since each LED needs about 20 mA for regular operation, I guess 2 or 3 won't be a problem. Btw, they must be connected in parallel, since the output is only about 4V, which means the currents will be additive (20mA per LED).

06-15-2012, 05:57 AM	#4
itakatz Junior Member Posts: 6 Karma: 10 Join Date: Jun 2012 Device: Kindle Touch	Thank for the info The information on the battery is the total capacity, not current (therefore it is measured in mAh, which is milliamps per hour. 1920 mAh means you can get a current of 1920 mA for one hour, or 192 mA for 10 hours, etc. But it doesn't give information about the maximal current you can draw from the terminals without damaging the device. Since each LED needs about 20 mA for regular operation, I guess 2 or 3 won't be a problem. Btw, they must be connected in parallel, since the output is only about 4V, which means the currents will be additive (20mA per LED).