Mutchus

This Mini Voltage Source with Adjustable Current Limit variable is very simple and efficient, ideal for small shippers or circuits that require a current limiter with adjustable voltage that this circuit can vary from a few mA up to 2 A and voltage 1.225v up to 12V or more, depending on the power supply.  Once the current reaches the limit set by the 100R resistor, transistor BC547 begins to act on the voltage regulator in the Adj pin and the output voltage starts to decrease. If the output is shorted, the output voltage will reduce to almost zero, as a kind of protection. Adjustable Voltage and Variable Current Limiter Circuit Diagram Adjustable Voltage and Variable Current Limiter Circuit Diagram

Here is a deluxe version of the simple charge rate limiter, using the same idea but with the ability to charge two packs simultaneously from a single wall charger. For circuit description and parts list, see the simple charger page. Since wall chargers provide about 55mA, you should not use this dual circuit to charge batteries at rates greater than 27mA (for a total of 54mA).