This project is for Transistor Based 12V Emergency Light Circuit system, which gives light when main power fails. The circuit uses transformer, bridge rectifier, transistor, relay, battery and few other components. When AC supply is present, battery charges and lamp stays OFF and when AC power goes OFF then battery gives supply and lamp turns […]
LED and Lamps
220V Emergency Light Circuit without Transformer
Like our previous tutorial on emergency light circuit, here is another post on 220V Emergency Light Circuit without Transformer. Today, power cut is common problem, so emergency light is very useful, as it gives light when mains supply is OFF. Usually, emergency light uses transformer but transformers are costly and bulky, therefore, this circuit is […]
Easy Emergency Light Circuit using Transistors
Power cut can come anytime, so our room becomes dark and feels very scary and bad. So, this small circuit gives light instantly, also there is no switch needed and no tension. Then light turns ON automatically and this happens because of simple and Easy Emergency Light Circuit using Transistors. Now, the circuit works like […]
Simple LM337 Based Precision LED Driver Circuit
LED needs stable current and when current becomes high then LED may burn, therefore, a regulator circuit is useful. This article is for Simple LM337 Based Precision LED Driver Circuit which is an negative adjustable voltage regulator but however, it can also control current. In this circuit the LED current stays stable and even if […]
Transformerless LED Display Circuit using Capacitor Dropper
LED displays are used in many small electronic devices and normally we need a transformer power supply, but however transformer makes the circuit big and costly. Therefore, a capacitor power supply is a good alternative which is small and is with low cost and is easy to build. In this circuit a capacitor dropper supply […]
Random LED Number Generator Circuit
This circuit is for simple Random LED Number Generator Circuit using IC CD4017 decade counter and IC CD4011 NAND gate. It works on 9V power supply and the LEDs in the circuit represent the numbers. When we press the switch, one LED remains ON, because the counter runs very fast and the final LED looks […]





