In part 1 of Dissecting A Smart Battery I mentioned that smart batteries have contained within them specialized hardware that when working in concert provides the power necessary to run a device such as a PDA, digital camera, or ipod player. Continuing the dissection of a smart battery this article of the series will look at the smart battery"s fuse, charge and discharge FETs, the cell pack, and the sense resistor (RSENSE) to discover what role they each play within the smart battery.

Before we begin let"s just recap some of the specialized hardware within the smart battery:

1. the connector
2. the fuse
3. the charge and discharge FETs
4. the cell pack
5. the sense resistor (RSENSE)
6. the primary and secondary protection ICs
7. the fuel-gauge IC
8. the thermistor
9. the pc board
10. the EEPROM
11. the SMBus

The Smart Battery Fuse

When we discuss fuses in relation to electronics we are speaking directly of a fusible link that is responsible for protecting the device from over current. Fusible links have a metal wire that melts when heated to a predetermined electric current rating. When melted the electrical circuit is opened and thereby protecting the circuit from an over-current condition. The obvious concern here is the selection of the fuse - an improperly selected fuse will not protect from over-current conditions and the result will be a fire or damage due to a short circuits.

In a smart battery a typical fuse has three-terminal components that limit current flow based on the temperature, current, and or power across the heating wire. Besides temperature ratings other important factors when selecting the proper fuse to work with each smart battery is hold current, trip current, maximum battery voltage, and fuse size.

The Smart Battery"s FET (field effect transistor)

Smart batteries must have a series FET (field effect transistor) switch to open and protect the battery"s cells. A FET is a transistor that uses an electric field to control the conductivity of a particular 'channel' in a semiconductor material. FETs at times are used as voltage-controlled resistors. As such field effect transistors are chosen based upon their designed ability to dissipate on demand power.

The Smart Battery"s Cell Pack

The battery cell can be thought of as the holding area of the battery"s chemical. The battery cell pack is critical to the overall capability of the smart battery. Cell packs have to be designed and integrated based upon the vitals of the battery including chemistry type (Li-ion, Li-po, NICD, NIMH, etc.) cycle life, storage-capacity loss, shelf life, impedance, capacity at different rates of discharge and temperature, and mechanical and environmental requirements. It is critical to say the least.

The Smart Battery"s Sense Resistor

The final specialized hardware I want to review in this article is the sense resistor (RSENSE). In electronics, sense, is generally referred to the task of producing the correct voltage. Current not temperered will cause damage so sense resistors need to be integrated in order to control power and temperature.

In my next article on the dissection of a smart battery I will cover secondary protection ICs, the fuel-gauge IC, the thermistor, the pc board, and the EEPROM.

Autor: Dan Hagopian

Dan Hagopian You have permission to publish this article electronically or in print, free of charge, as long as the bylines are included with link. Dan Hagopian of http://www.batteryship.com is a known electronics author that specializes in portable power gadgets. His work can be found on the BatteryShip blog at http://www.batteryeducation.com He frequently writes about pda batteries, ipod batteries, general battery technology for our mobile world, new fuel cell technology and interesting power related inventions. For further information please visit http://www.batteryship.com where you can also find PDA battery replacement kits, smartphone batteries, twoway radio batteries, barcode scanner batteries, camera batteries, and camcorder batteries.

Added: March 28, 2007
Source: http://ezinearticles.com/

In this day and age we can all be forgiven for not being aware of the latest technology and actually how it all works. I know that I am personally a lard-head when it comes to some of the changes and new innovations. I prefer to ignore complex things and, therefore, end up playing catch up all the time. However, some things are worth finding out about and, in fact, are not as complex as they first seem.

You may have heard mention of a service called VOIP. It stands for Voice over IP, which is a means of communicating with others using the internet.

Basically, VOIP records your voice and sends it electronically to the receiver- working just like a telephone. You can even hook the service up to your regular telephone with an adapter- making it extremely cost effective as your new phone, since some services offer free VOIP.

You will need a high-speed internet connection to use it- but the benefit of saving money is well worth an upgrade if needed. The major drawback is that you can not connect to emergency numbers like 911- a very alarming fact. If you want to make such an emergency call, you will have to use a cell phone or land-line phone instead.

Many use VOIP because of the cheap rates, and some services offer VOIP free. It is expected to gain much more support in the future, as internet connection speeds will improve in time- making the potential customer base much larger. If you haven"t already, you may want to check into VOIP, and tap into the large amount of savings you could be experiencing with this new technology.

Autor: Eric Hartwell

Eric Hartwell oversees "The World's Best Homepage" intended to be a user-generated resource where YOUR opinion counts. Anybody can contribute and all are welcomed. Visit us to read, comment upon or share opinions on computers and visit our associated site articles for free.

Added: March 28, 2007
Source: http://ezinearticles.com/

Bluetooth can be defined as a wireless form of communication that enables devices to send and receive communication. It is a global initiative set up by manufacturers such as IBM, Intel, Ericsson, Toshiba and Nokia to create a standard for linking up devices such as mobile phones, mobile PCs, handheld computers and other peripherals. Bluetooth relies on short-range radio technology to allow the wireless connectivity. The key features of Bluetooth are robustness, low power and low cost. Both data and voice transmissions can be handled simultaneously. Examples of innovative solutions which users can perform include printing or faxing capabilities, synchronising PDA, laptop or computer and making or receiving calls from a mobile phone, with many more applications available.
Wifi is short for 'wireless fidelity' and is a limited-range wireless networking code which is used in many airports, hotels or other services, who offer public access to Wifi networks, to allow people to log on to the Internet and receive emails whilst on the move. As Wifi is a reasonably fast method of transmitting information in wave form, it is often used in computers and also notebooks. In future, it will become possible to access the Internet from just about anywhere, without the use of any wires. The advantages of using Wifi are that the networks are fairly cheap and straight-forward to set up. Wifi is also quite inconspicuous and can hardly be noticed unless it is being looked for specifically, whilst in a Wifi 'hotspot.' For a wireless network to be created, communication is transferred like a two way radio, using radio waves.
Both Bluetooth and Wifi have both been in the news more especially in recent years. Both technologies are relatively new on the market and, with time, a trend may be seen favouring one or the other. As more and more Bluetooth devices become available, most people will own devices for Bluetooth and Wifi. There are several advantages for opting for Bluetooth networking over Wifi and vice-versa. WiFi and Bluetooth are actually very different technologies with very different reasons to exist. The question should not be Bluetooth versus Wifi but more how Bluetooth can work with Wifi.
Advantages of Bluetooth
Bluetooth can connect devices from point-to-point and probably better on security than Wifi, as it can cover shorter distances. In addition, Bluetooth offers an optional two levels of password protection. Up to seven devices can be connected at any one time which makes it easier to find and connect the device being searched for, as Bluetooth highlights itself to the other devices. Bluetooth technology is also more ideal for consumer electronics devices as it has a smaller power requirement. Microsoft have also recently announced that Bluetooth support will be built into a future version of windows XP. Another advantage is concerning voice communication. For an office or home environment, Bluetooth can be used in a cordless phone within a 10m range, without the need to be passed around. It is not likely that Wifi technologies will have a required voice-over-IP to support voice communication, within the near future. Bluetooth was also introduced much earlier in the market and is installed in much more user devices and products, in comparison to Wifi products.
Advantages of Wifi
The most prominent advantage which Wifi has over Bluetooth is that Wifi operates at a much faster rate - of about 11mbps, whereas Bluetooth only operates at a much slower rate of around 720kbps. This makes Bluetooth too slow for video transfers or for moving large amounts of large photo images from a digital camera. Wifi is also designed to link up entire networks, rather than computer to computer. Wifi can achieve this too but it is not its real purpose. Originally intended to be used for mobile computing devices, such as laptops, it is now often being used for increasingly more applications, such as Internet access, gaming and basic connectivity for home electronic appliances such as televisions or DVD players. Wi-Fi may be used by cars in highways, as standards rise in development, in support of an Intelligent Transportation System to increase safety, gather statistics, and enable mobile commerce.
Having taking in the advantages of both forms of communication, it can not be said that one is better than the other. The two wireless protocols can be used to perform separate things and it is not essential to opt for one, rather than the other. Bluetooth should be the first choice for when connecting single devices, only when speed is not an issue. It has a short range of approximately 30 to 60 feet and common applications can include sharing printers, syncing PDAs or using a mobile phone as a modem. As time goes by it will be very interesting to see how both Bluetooth and Wifi develop and what new uses they will have and for what devices.

Autor: Matthew Barrett

Think4 supplies consumers and businesses with a vast spectrum of IT and technology products encompassing systems, components, peripherals and consumables, such as Bluetooth / WiFi networks, PCs /servers, handheld PDAs, laptops, computer memory, MP3 players, sat nav systems, LCD and plasma TVs. We focus on supplying the latest products available at competitive prices with prompt delivery. Find all IT, electronics products and accessories at Think4.com - the home of informed technology shopping.

Added: March 28, 2007
Source: http://contentdesk.com/view.php

Despite being slightly dismayed at the tentacle-like look of this device, we can see the wisdom behind the SendStation PocketDock AV. As its name suggests, it's a very small iPod dock that packs a lot of power in its small and relatively inexpensive (US$36.95) frame.

You can connect composite or S-Video, if iPod Video is your thing. You can hook up left and right speakers. You can connect a microphone and even a plain old USB device, like a laptop, for heavy-duty jamming or viewing.

They will be out in stores starting early April. One thing you might want to do until then is figure out where to store all those cables when they're not all in use. They're all connected, yes, but that can be an inconvenient thing since a case is not included.

source: www.htlounge.net

The first iPhone ad that aired on television.

Personal review of the Apple iPod Shuffle Find more video product reviews in the Electronics or MP3 Players categories at www.expotv.com Videopinions are Expo TV members showing and telling in full motion video what they love and hate about the products and services that make their world go round. Videopinion user reviews are unbiased, personalized, product demonstrations submitted by Expo TV members. Go to expotv.com the next time you’re doing product research to find the best video reviews by experts and users, or submit a Videopinion of your own! Tags: Apple iPod Shuffle MP3 Player