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Transistor Circuits

High Current 5V 3A Voltage Regulator Circuit

Last updated on 22 March 2026 by Admin-Lavi Leave a Comment

This High Current 5V 3A Voltage Regulator Circuit gives regulated 5V output with high current capacity. Normal 7805 IC gives around 1A current, but in many projects, this current is not enough, so we add a power transistor to increase current up to around 3A. This circuit also uses bridge rectifier and filter capacitors to […]

Filed Under: Power Supply Circuits, Transistor Circuits

Simple Backup Power Supply Circuit using JFET Transistor

Last updated on 21 March 2026 by Admin-Lavi Leave a Comment

In this article, the circuit gives temporary backup power to low current electronic systems as it uses JFET transistor like 2N3819. This Simple Backup Power Supply Circuit using JFET Transistor which charges a capacitor at 15V input and gives approximate 4V-6V output during power failure, because it depends on transistor characteristics, resistor tolerance and load […]

Filed Under: Power Supply Circuits, Transistor Circuits

Overcurrent Protection Circuit using Transistor and FET

Last updated on 18 March 2026 by Admin-Lavi Leave a Comment

This circuit shows about FET overload current protection using transistor and MOSFET. If the load draws too much current or the output gets short-circuited then this Overcurrent Protection Circuit using Transistor and FET can help you. The main purpose of this circuit is to protect load from high current, like when current increases above limit […]

Filed Under: Security and Protection, Transistor Circuits

Transistor Based 12V Emergency Light Circuit

Last updated on 18 March 2026 by Admin-Lavi Leave a Comment

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 […]

Filed Under: Battery Charger Circuits, LED and Lamps, Transistor Circuits

220V Emergency Light Circuit without Transformer

Last updated on 18 March 2026 by Admin-Lavi Leave a Comment

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 […]

Filed Under: LED and Lamps, Transistor Circuits

Easy Emergency Light Circuit using Transistors

Last updated on 17 March 2026 by Admin-Lavi Leave a Comment

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 […]

Filed Under: Battery Charger Circuits, LED and Lamps, Transistor Circuits

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Recent Posts

  • High Current 5V 3A Voltage Regulator Circuit
  • How to Increase 7805 Output Voltage using Diodes
  • Simple Backup Power Supply Circuit using JFET Transistor
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  • 7806 Based 6V 1A Regulated Power Supply Circuit

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