In the following post I have explained a simple yet useful car speed limit warning indicator circuit which can be used in vehicles for getting an instant indication of a possible over speed limit conditions. The idea was requested by Mr. Abu-Hafss. Technical Specifications: Shall appreciate, if you could design a circuit to warn with […]
Indicator Circuits
Car Radiator Hot Indicator Circuit
The proposed circuit is very useful which warns the car driver before hand once the radiator gets heated up above the preset level. How it Works The working of this circuit is very simple and works off on the car battery. The familiar IC555 is used here which is the heart of the circuit. The […]
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 […]





