In the following post I have explained a simple low battery indicator circuit by using just two inexpensive NPN transistors. The main feature of this circuit is its very low stand by current consumption. The Circuit Concept We have so far seen how to make a low battery indicator circuits using a 741 IC and […]
Battery Charger Circuits
Bicycle Dynamo Battery Charger Circuit
In this post I have explained a simple constant current bicycle dynamo battery charger circuit which can be used for charging a Li-Ion or Ni-Cd battery from a bicycle dynamo electricity source. The idea was requested by Mr. Saif Khan. Technical Specifications I want to charge a battery through a dynamo fitted to a cycle. […]
Super Capacitor Charger Theory and Working
In this post I have explained a super capacitor charger circuit for charging super capacitors which converts a 12V car battery voltage to an elevated 16V for charging a bank of super capacitors. The idea was requested by Miariver. Super Capacitor for Peak Power Compensation First thanks for keep publishing this blog is very helpful, […]
Accumulators Explained [Rechargeable Batteries]
Unlike dry batteries, whose stored electrical energy can only be used once, accumulators have the immense advantage of reversibility, which translates into the possibility of a series of charge/discharge cycles. This means that they can undergo a series of charge/discharge cycles. They are found in applications that may require more power, such as starting the […]
Precise Battery Capacity Tester Circuit – Backup Time Tester
The precise battery capacity tester circuit explained in the following article can be used for testing the maximum backup capacity of any rechargeable battery in real time. By Timothy John Basic concept The circuit works by practically discharging a fully charged battery under test through constant current, until its voltage reaches the deep discharge value. […]
Laptop Power Bank Circuit
In this post I have explained how to build a simple laptop power bank circuit which can be used for charging a laptop battery during travelling or during outdoor trips. This device can be specifically useful on situations or places where an AC mains outlet is unavailable or difficult to find. Why Laptops Need a […]





