Cell Phones and PDAs

More Power in the palm of your hand

The era of the flip style cell phone as we know it today started in the 60s with communicators used by the crew of the USS Enterprise on the TV series Star Trek. Who would have guessed a TV show designed something we'd take for granted decades later. The result of smaller and smaller transistors means integrated circuits. Chips that replace entire circuit boards have gotten smaller and more efficient. This greater efficiency means electronic tasks are performed with less energy and can be performed more quickly.

The reverse-snowball effect of miniaturizing electronics has been a largely unexpected side effect. The rate of Moore's Law has so far provided us sweeping advances in computing power. In 1968, Stanley Kubrick envisioned a computer so smart it had all the intelligence and shortcomings of a living person. But in 1968, Kubrick saw the electronic brains behind HAL as taking up a room sized "crawlspace" with piles of modules. Who would have guessed that by the time artificial intelligence reached fruition it would probably be on tiny computers the size of a small box, or possibly even a handheld device. Buck Rogers was on the money with Dr. Theopolis, the wearable professor.

Today everything is made in miniature, even computers themselves. It's not just transistors that have shrunk in size; powerful transmitters that send microwaves across town and receivers that pick up signals beamed from space are shrinking. Just about anything that has traditionally been large can now be made so small that it's forcing us to re-think how we use these technologies.

The components that perform any given job can be made so small that the sizes of the electronic circuits are no longer even an issue with most devices. The biggest hurdles facing further downsizing of electronics are power supply, memory and heat dissipation. Some of the devices we can make in miniature still consume large quantities of power requiring a battery pack that increases the size of the device by several times. The pressure on engineers today is to make smaller battery packs that hold longer charges.

Anytime transistors operate at high frequency, a tremendous amount of heat is generated. Most integrated circuit components must also have a heat sink built-in or have enough air moving to dissipate the heat they generate so they don't simply self destruct. This adds more engineering riddles. Memory is also an issue with computing devices. There are two main ways to store data on our handhelds: memory and micro-hard drives. Either option has its own built in riddles. It must be made cheaply and reliably.

The most reliable is non-volatile memory on an EEPROM chip that can be reprogrammed and will retain a user's data without power. This is the most expensive option and yields the least amount of memory per space. RAM is cheaper and takes up less space for any given capacity, but requires a small charge to retain any data. Micro-hard drives are seen as a great balance; they're cheap and hold huge quantities of data with no power, once it's been written to the drive. But they're not as fast as non-volatile memory. They also have greater power requirements- the hard drive includes moving parts adding a whole new dimension to the device.

Moving parts mean more heat and greater energy requirements. Some even believe the micro-hard drive is more prone to failure. Although it must be said, that the failure rate of most hard drives is far beyond the scope of any gizmo's lifespan. A replacement for a hard drive that has worn out from age is likely to cost more than replacing the whole device. It will be interesting to see the direction of these micro-technologies in the near future.

In this section we'll take a look at all these handheld and wearable gadgets. Whether they use batteries, contain LCD displays or use memory cards, handhelds are absorbing the jobs conventionally performed by much larger devices, or even people. Who knows, maybe we'll soon see an artificial intelligence driven Doctor you can hang around your neck.