With speeds clocking hundreds of times faster than the first commercially available IC op amps, today's high-speed amplifiers cost less and consume less power than their predecessors. This evolution may be the best indicator of what's to come for amplifiers.
Significant advances in process technology-specifically, complementary bipolar processes that enable gigahertz speeds-make it possible for amplifiers to deliver more performance at lower cost and higher power efficiencies than ever before. As a result, the cost per megahertz of bandwidth has decreased 10 times per decade since 1970, when the LM741 was introduced at about $3. This astounding progress has closely paralleled Moore's Law.
The use of silicon-on-insulator (SOI) or bonded wafers reduces parasitic capacitance and greatly increases the power efficiency in terms of speed-per-milliamp of supply current. These amplifiers can provide over 100 MHz/mA of supply current, which is critical in high-performance, low-power applications such as portable instrumentation.
Process technology is only one piece of the puzzle. Innovations in amplifier design have also moved the development curve along. For example, op amps couldn't achieve ultra-low noise (below 1 nV/Hz) and ultra-low distortion (-92 dBc at 10 MHz) until the arrival of some recent advances in input stage architecture and package pin-out configurations.
Further development in process technologies and amplifier design techniques will lead to even greater power efficiency, higher performance, and an increase in overall value in the amplifiers of the future.
