This article explains the main specifications, pinouts and application related information regarding the transistor NPN BJT 2N2222, 2N2222A, and also its complimentary PNP pair 2N2907 BJT Introduction In one of my earlier posts I have explained regarding a few low signal type of transistors like BC547, BC557 etc. Here we are going to study the […]
Newly Updated Circuit Projects:
Class-D Sinewave Inverter Circuit
A sinewave inverter using class-D amplifier functions by converting a small sinewave input frequency into equivalent sine PWMs, which is finally processed by an H-bridge BJT driver for generating the mains sinewave AC output from a DC battery source. What is Class-D Amplifier The working principle of a class-D amplifier is actually simple yet extremely […]
6 Useful DC Cell phone Charger Circuits Explained
A DC cell phone or mobile phone charger is a device which charges a cellphone from an available DC supply source. The device converts the unregulated DC source into a constant current and constant voltage output which becomes safe for any mobile phone charging. In this article I have explained how to build DC to […]
5V 3 Amp Fixed Voltage Regulator Circuit using IC LM123
In this article I have explained the main specifications, datasheet and circuit application notes of the IC LM123, LM323 which are precision 5V, 3 amp fixed voltage regulator IC. These ICs can be used for generating highly regulated 5 V output with a an impressive 3 amp current output. The maximum input to the IC […]
Simple Electronic Fuse Circuit
In this article we investigate a electronic circuit design which works like a conventional fuse for safeguarding any electrical system from overloads, over-current, short circuit and related fire hazards. However, the main advantage of this electronic fuse is that it does not require frequent replacements like mechanical fuses, instead it can be reset with a […]
Bluetooth Car Ignition Lock Circuit – Keyless Car Protection
This circuit will allow the user to lock his car ignition using his phone Bluetooth, meaning the ignition can be locked/unlocked only through a specific code from the user’s cellphone Bluetooth. Overview In one of my earlier posts I have already explained how to hack a Bluetooth headset and use it for any desired switching […]