The proposed circuit was requested by one of the avid readers of my blog. It is a low battery warning indicator circuit using op amp IC 741 and can be used for monitoring a particular low battery voltage threshold. Circuit Operation The circuit may be understood with the following points: The entire configuration is wired […]
Battery
3 LED Battery Level Indicator Circuit
The proposed 3 LED battery level indicator can be typically used for monitoring a 12 V lead acid battery charge level, through 3 distinct LED illumination. The entire circuit is built using just a couple of BJTs , a few zener diodes, resistors and LEDs. Different Ways to Check Battery Voltage A hydrometer is perhaps […]
18650 2600mAh Battery Datasheet and Circuit Diagram
In this article I will try to explain the main specifications and datasheet of the Li-Ion cell 18650 2600 mAh, which is one of the most popular Li-ion batteries, and preferred by all electronic professionals due to its high efficiency, in terms power delivery and compact dimensions. Li-Ion batteries are one of the most advanced […]
12V Battery Charger Circuits [using LM317, LM338, L200, Transistors]
In this article I will be discussing a list of simple 12V battery charger circuits which are very easy and cheap by its design yet extremely accurate with its output voltage and current specs. All the designs presented here are current controlled meaning their outputs will never go beyond a predetermined fixed current level. UPDATE: […]
Make this 18V Cordless Drill Battery Charger Circuit
In this post I have explained how to build and use a 18V battery charger circuit for a cordless drill machine. The idea was requested by Mr. Chibuzo. Technical Specifications The Design Whether it’s a lead acid battery, a Ni-Cd or a Li-ion, this multipurpose battery charger shown below can be applied for any of […]
Low Battery and Overload Protection Circuit for Inverters
A very simple low battery cut-off and overload protection circuit has been explained here. The figure shows a very simple circuit set up which performs the function of an overload sensor and also as an under voltage detector. In both the cases the circuit trips the relay for protecting the output under the above conditions. […]





