Wednesday, February 20, 2008

Buck Boost Converter - Part 3

The buck-boost converter is a type of DC-DC converter that has an output voltage magnitude that is either greater than or less than the input voltage magnitude. It is a DC-to-DC converter is a device that accepts a DC input voltage and produces a DC output voltage. Typically the output produced is at a different voltage level than the input. It is a switch mode power supply with a similar circuit topology to the boost converter and the buck converter. The output voltage is adjustable based on the duty cycle of the switching transistor. Also, the polarity of the output voltage is opposite the input voltage. It has the same structure as the, flyback converter with an inductor instead of a transformer. One drawback of this converter is that the switch does not have a terminal at ground; this complicates the driving circuitry. It is used in USB applications and UPS for computers.

Tuesday, February 19, 2008

Buck Boost converter - part 2

DC to DC converters are important in portable electronic devices such as cellular phones and laptop computers which are supplied with power from batteries. Such electronic devices consists of sub-circuits with each sub-circuit requiring unique voltage levels different from that supplied by the batteries,sometimes higher,sometimes lower than the battery voltage,sometimes even negative voltage. Additionally, the battery voltage declines as its stored power is drained. DC to DC converters offer a method of generating multiple controlled voltages from a single variable battery voltage, thereby saving space instead of using multiple batteries to supply different parts of the device.

Monday, February 18, 2008

Buck Boost Converter - Part 1

A dc power supply consists of a transformer to step down the 230V, 50Hz from the mains to a lower level ac voltage, a rectifier section to converter ac voltage to dc voltage, a filter section to reduce the ripples in the rectifier output, voltage regulator section to provide a constant, regulated output and a dc to dc converter section to convert the output of the regulator into another voltage level according to the needs of the application for which the supply is going to be used.

Friday, February 15, 2008

My Mobile

The mobile that I am using right now is the Samsung X620. This is my first mobile which was bought by my parents. Even though it has got wretched woefully, I am using it since I can't afford to lose a new mobile. So I ll be using it as long as it works. The keypad has been damaged already.

Thursday, February 7, 2008

Will Robo dissapoint like Shivaji

Lots of expectations and hype were given to Rajini's Shivaji. Even though the movie did well at the box-office, the movie was a dissapointment in all aspects. The movie just had no logic and flair. Shankar has given his worst movie of all time. The question is, will Robo be the same?

Saturday, February 2, 2008

Finished Gears of War at last

I started playing Gears of War with my friend in my XBOX 360 a few months back. We started playing it really well and we completed about half the game in just 2 days. But after that we were unable to continue due to some reasons. But finally we finished it yesterday. We were really happy.