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Saturday, 17 May 2014

USB Battery Charger for NiCd

                                                      



This is a simple charger for nickel-cadmium battery (NiCd) that can be connected in your USB port. The charging scheme employs only a constant current charging. The two NiCd cells are connected in series and charge at 200mA current. Charging current is controlled by zener diode D1 and resistor R1. You can increase or decrease the current by using the approximate equation:
Current = VD1/R1; where VD1 is the zener voltage.
The use of D2 is to limit the voltage across the battery, thus protect it from damage. Charging time of the fully discharged battery is given by the formula:
Time = Battery rating / 200mA ; where Battery rating is in mAH.

Example: battery rating 220mAh;
Time = 2200mAH / 200mA = 11 hours; meaning do not let battery charged more than 11 hours.


                                                                   




                                                           




 

2 comments:

  1. यदि आपको मोबाईल के बारे मे कुछ भी पुछना हो तो लिखे

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  2. यदि आप का मोबाइल चार्जर खराब हो गया है तो वह ठिक हो सकता है आप घर बैठे ही मोबाइल चार्जर ठीक कर सकते है आप को बाजार से नया चार्जर नही लाना पडे्गा

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