In this post I have explained 5 useful power supply failure indicator circuits which can be used to get an instant indication regarding an input power failure situation. This post includes the following 5 types power failure indicator circuits: Main Function The main function of the proposed power failure indicator circuits is to alert or […]
Indicator Circuits
Simple Water Level Indicator Circuits (with Images)
A water level indicator is an electronic circuit which indicates the various levels of water inside a tank. This happens when rising or dropping water levels come in contact with the respective water sensors arranged step wise inside the water tank at different depths. In this post I have explained 2 interesting ways to make […]
Flashing LED Battery Low Indicator Circuit
In this post I have explained a simple low/normal battery voltage status indicator circuit through a flashing and a constant LED, where the flashing LED indicates a normal status while the solid indicator warns against a low battery condition. The idea was requested by Mr.Alf. Technical Specifications Hi, I found and built your “Low Battery […]
Battery Current Indicator Circuit – Current Triggered Charging Cut off
In this post I have explained about a simple battery current sensor with indicator circuit which detects the amount of current consumed by the battery while charging. The presented designs also have an auto cut off when the battery stops consuming current at its full charge level.. Why Current Drops as Battery gets Charged We […]
Up/Down LED Indicator using LM3915
This circuit can be used for moving an LED bar graph in the upward sequence or downward sequence through a couple of push button switches. The concept can be implemented for many other useful applications. Using IC LM3915 In many circuit applications we require a digitally operated control system enabling an upward or downward control […]
Make a Simplest Temperature Indicator Circuit
A very simple temperature indicator circuit can be built by interconnecting a single transistor, a diode and a few other passive components. Using Transistor as a Heat Sensor As we know that all semiconductors have this “bad habit” of changing its basic characteristics in response to ambient temperature changes. Especially basic electronic components like transistors […]





