Gone are the days of carrying around ten 3.5-inch floppies or if you were lucky a Zip disk or two. It used to be that if you wanted to carry around data via the old “Sneaker net” you only had a hand full of choices. All of these choices were bulky, fragile, temper mental, and at times extremely impractical. Nowadays we need more, much more! Luckily developers realized that Flash memory was the perfect non-volatile replacement. Well, many years and many USB Flash drives later, one of the top competitors in the memory market finally decided to get its feet wet; that’s right, Crucial Technologies. If you haven’t already figured it out from the picture above, the Crucial Gizmo! has arrived. The Gizmo! comes in three tasty little flavors: 64, 128, and 256MB models are available and all within the price range of 36 to 90 dollars. Today we’ll be looking at the 64MB version, small as it may be, anything that replaces 44 floppies is a godsend in my eyes.

Crucial Supplied Details:
The Crucial® Gizmo!™ USB flash drive, a miniature, portable flash storage drive that plugs into a computer's Universal Serial Bus (USB) port. This high-density alternative to the traditional floppy disk stores digital documents, music, and photographs and conveniently transfers data from one USB-enabled computer to another. About the size and weight of a pack of gum, the Gizmo! drive slips easily into a pocket, purse, or briefcase. The Gizmo! drive is compatible with both USB 2.0 and 1.1 ports. A true Plug and Play™ solution, the Gizmo! drive automatically appears as a removable drive when plugged in to the USB port of a desktop or notebook.

Sounds great! Before we jump right into the review, let’s get a general background on how the technology works. Flash memory is a type of EEPROM chip. It has a grid of columns and rows with a cell that has two transistors at each intersection (see images below). The two transistors are separated from each other by a thin oxide layer. One of the transistors is known as a floating gate, and the other one is the control gate. The floating gate's only link to the row, or word line, is through the control gate. As long as this link is in place, the cell has a value of 1. To change the value to a 0 requires a curious process called Fowler-Nordheim tunneling.
Tunneling is used to alter the placement of electrons in the floating gate. An electrical charge, usually 10 to 13 volts, is applied to the floating gate. The charge comes from the column, or bit line, enters the floating gate and drains to a ground.
This charge causes the floating-gate transistor to act like an electron gun. The excited electrons are pushed through and trapped on other side of the thin oxide layer, giving it a negative charge. These negatively charged electrons act as a barrier between the control gate and the floating gate. A special device called a cell sensor monitors the level of the charge passing through the floating gate. If the flow through the gate is greater than 50 percent of the charge, it has a value of 1; when the charge passing through drops below the 50-percent threshold, the value changes to 0. A blank EEPROM has all of the gates fully open, giving each cell a value of 1.

The electrons in the cells of a Flash-memory chip can be returned to normal ("1") by the application of an electric field, a higher-voltage charge. Flash memory uses in-circuit wiring to apply the electric field either to the entire chip or to predetermined sections known as blocks. This erases the targeted area of the chip, which can then be rewritten. Flash memory works much faster than traditional EPROMs because instead of erasing one byte at a time, it erases a block or the entire chip, and then rewrites it.

Now for the obligatory car adage I like to fall back on each time. You may think that your car radio has Flash memory, since you are able to program the presets and the radio remembers them. But it is actually using Flash RAM. The difference is that Flash RAM has to have some power to maintain its contents, while Flash memory will maintain its data without any external source of power. Even though you have turned the power off, the car radio is pulling a tiny amount of current to preserve the data in the Flash RAM. That is why the radio will lose its presets if your car battery dies or the wires are disconnected. As you can see flash memory is well suited to portable non-volatile memory storage.