BSI Pin in Mobile Battery

Mobile phone battery requires only two pins for charging, then why there is a third pin? The question is definitely a curiosity generating one. The third pin called BSI pin performs very important functions and act as an interface between the Mobile phone and the Battery. When the battery is removed, without switching off the Mobile phone, the BSI circuit is first interrupted which convey the information to the processor to shut down all communications to prevent damage. To communicate with the BSI, the battery pack also has a BSI pin. BSI stands for Battery Status Indicator or Battery System Indicator.


Human Personality

Human personality is reflected in the way of behavior, daily activities and doing competitive works. Human personality can be classified into Type A, Type B and Type AB personalities according to researchers. Type A behavior (TAB) or personalities have something to do with being competitive and most of them are workaholics. Type B personalities on the other hand are generally patient, relaxed, easy-going . AB personalities have mixed profile and cannot be clearly categorized as either Type A or Type B.

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Why Electricity is so Brutal? Fact File 11

Not always, but only when handled carelessly. Shock induced muscle tetany is the most important effect of current on the muscles. If a person touches the energized conductor, fore arm muscles contracts forcefully and fingers bend. So the person involuntarily holds the conductor. Therefore the victim will be unable to take the hand from the conductor.

As you know, electricity is the flow of electrons through a conductor from its source to the destination. If the conductor offers less resistance, the flow current will be fast and if the conductor has some resistance, the flow of electrons will be obstructed leading to slow movements which generate heat through friction.

Human skin is a semiconductor for electricity and current passes through the body to the ground just like the flow of current through the electric wire. This flow of current causes burning and shock. If the skin resistance is low, the chance of shock hazard is very high. Some people are more sensitive to current while others are less sensitive. Electrical safety measures are necessary while dealing with high voltage AC available from the power grid. Ignorance can lead to a fatal shock or fire hazards.

Remember, Electricity travels at the speed of light. Its flow is around 299,460 kilo meters per second so you will not get time to react because you can’t move faster than electricity. So the best way is staying out of its way.
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PIR Sensor Alarm


This simple alarm can be used to detect the movement of human beings at a distance of 10 meters.It works both day and night and beeps shortly when there is a human movement through its detecting range. It is ideal to monitor the entry passages, stair case, corridors etc. It is highly useful to monitor the human movements in Flats, Multi storied buildings, Shops etc. A relay can also be connected for activating lights, electric alarms etc. It can be used as a Personal alarm during journey to protect luggage.

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Cloud Computing

The system that performs the delivery of computing as a service over the network is the Cloud Computing. It is the service that provides shared resources and software information to the computers. In Cloud computing, computation, software, data access etc are provided to the end users. The end user can access the informations in the network without needing to understand the system’s components and infrastructure. The term cloud is used to represent the Internet system similar to the cloud drawing used in earlier telephone system to give point-to-point data circuits for the Virtual private network.

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Trick of White LED. Circuit Clinic 6


Introduction of White LED created a revolution in electronics field to replace the Fluorescent lamps in lighting systems. High power White LEDs are now widely used to make Ceiling lamps, Flood lights, Vehicle lamps, surgical instruments, Projectors etc. When compared to ordinary White LED, the high power LED consumes around 200-300 milli ampere and mounted on heat sink for heat dissipation. Majority of high power White LEDs are flat chips that will be easily destroyed if the voltage and current exceeds. So LED driver circuit is used for the  stable operation of the LED. The theory and working of LED is given in the previous post, so only the relevant facts about White LED is given here.
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The world of LED Circuit Clinic 5


I think, without an LED, the circuit will be incomplete. It is used as visual indicator in most of the circuits to confirm the working of a particular section. It is a simple diode with light emitting property and hence the name Light Emitting Diode. Its encapsulation has two electrode posts with a chip. When the chip is energized, it emits photons in the form of visible light. The colour of the light depends on the material in the chip. LED works in very low voltage as low as 1 volt. But the new generation White and Blue LEDs require minimum 3 volts to get sufficient brightness. Introduction of the white LED, created a White revolution in the field of LED lighting. Due to its low current consumption, modern lighting system is gradually changing to LED lighting. In addition to White LED, various other types like, Pink LED, Bicolour LED, Multi colour LED etc are also in use . Infrared LED emits light in the Infrared region and hence invisible to eye.
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Zener and Voltage regulation Circuit Clinic 4



Zener is not an obsolete device as some designers think. Even though voltage regulator ICs are used widely for precision voltage regulation, Zener diodes are still in use to drop voltage at some sections of the circuit board. Zener is a simple semiconductor device and looks like the glass rectifier diode 1N4148. It generates a fixed voltage output depending on its value. It is designed to operate in the reverse breakdown region. It is always connected in the reverse biased mode with the cathode to the positive supply. Zener diode requires a series resistor to limit current across it, without which the device will be damaged. Zener diodes are available in various voltage ratings from 1.1 volt to 68 volt. Power Zener diodes are also available for industrial applications. They can handle high voltage and current. It’s lead identification is similar to other diodes. The lead near the black or white band is cathode which goes to the positive supply.

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Diode in action Circuit Clinic 3


What is the function of a diode in the circuit? It  simply act as a switch to pass current only in one direction from Anode to Cathode. So it is essential in all most all circuits. Diodes are semiconductor devices with a p-n junction to allow the one way flow of current. This condition is the forward biasing. If the current flow is reversed, the diode enters into the reverse biased mode and prevents the flow of current. Diodes perform many functions in an electronic circuit like rectification, clamping, protection, voltage multiplication, signal detection etc. Major types of diodes are power diodes, signal diodes, zener diodes, photo diodes, LED etc. Schottky diodes are fast recovery diodes ideal for switching applications.
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