The development of the digital computer over the last 30 years has really been synonymous with developments in semi-conductor technology. From the invention of the transistor at Bell Telephone Labs in 1947, the rate of progress has been ever quickening. In 1968, Jack Kilby, then working at Texas Instruments, produced the first 'integrated circuit', which contained just a couple of transistors on a chip about 1 centimetre square. A few years later, the first 'microprocessor' chip appeared. This came about as a result of some lateral thinking on the part of the team at Intel who were producing calculator chips. It was realised that it would make more sense to produce a single device which could be programmed to do different jobs, rather than a number of dedicated devices.

Since then, ever more powerful devices have been produced with associated improvements in all manner of silicon support devices, from ROMs to RAM's and everything in between! This pace of development seems to show no sign of halting and the next step will probably be towards silicon systems, with all the back up store contained in non-volatile RAM. One particular development in this direction is the wafer- scale integration which Sinclair are known to be working on. Here, individual chips are left all together as a wafer, rather than being individually packaged. The main problem is that software accessing of these devices will need to be adaptive in order to avoid any defective locations within the interconnected chips. By this means, it is anticipated that a silicon 'disk' of up to 3 megabytes could be produced but without any of the usual hardware.

The history of electronics » Digital electronics

Computers

understand only two numbers, 0 and 1, and do all their arithmetic operations in this binary mode. Many electrical and electronic devices have two states: they are either off or on. A light switch is a familiar example, as are vacuum tubes and transistors. Because computers have been a major application for integrated circuits from their beginning, digital integrated circuits have become commonplace. It has thus become easy to design electronic systems that use digital language to control their functions and to communicate with other systems.