Bicycle Dynamo Usb Charger Circuit. But they assume the person making the charger knows how to read a circuit diagram. A bicycle dynamo output can be used to power variety of devices in this article we are discussing about diy bicycle usb charger circuit that will use the output power of your bicycle dynamo and produces a regulated 5v output to charge your devices which require 5v charging input for example.
Rx is the current control resistor which must be selected as per the charging current specifications by using the following formula. This allows the motor to charge the boostcap 140 f which in turn supplies power to the mintyboost circuitry. In this post i describe how i made a diy bicycle dynamo usb charger for smartphones and battery packs.
There is a wide array of dynamo usb chargers available 24 of em in fact and while most do an adequate job of keeping your electronics charged at high speeds there is only a select few which can provide a decent charge at touring speeds dynamo usb charger technology is actually improving at an incredibly fast rate.
The ultracapacitor stores energy to continuously charge the usb device even while the bike is not in motion. We use hub dynamos systems all the time and on all kinds of bikes. However hub dynamos don t produce a regulated 5v voltage to charge my devices over usb so i created a simply circuit that will transform the unregulated ac voltage from the dynamo to regulated dc 5v. Often just one person are designing.