Topic 3 Microelectronics and Wireless Communication Technology
Introduction
<Microelectronics> A branch of electronics that deals with
miniature components, starting few decades after the
introduction of the semiconductor transistor in the late 1940s.
The term microelectronics describes a group of ten
technologies that integrate multiple devices into a small
physical area, generally a silicon (or other) wafer. A common
example is an integrated circuit or microchip found in
computers or mobile phones. There are 10 broad categories of
microelectronic devices, which are summarized below.
1. Field Programmable Gate Array (FPGA)
An FPGA is an array of regular logic blocks that may be configured
to operate in a particular way by loading a software definition of the function. Changing the
software definition can then reconfigure the device. They are economical to use in low volume
applications, as the non-recurrent engineering costs are lower than for other types of
microelectronic devices. With special time to market advantages such as fast programming and
testing, the devices are an easy, low cost entry point for Australian manufacturers considering
product innovation with microelectronics. The EDA design software to complete the design flow is
also cheaper to purchase from leading software vendors.
2. Digital Application Specific Integrated Circuit (Digital ASIC)
Integration of complex digital systems into a single digital ASIC in CMOS (complementary metal
oxide semiconductor) technology is the most common form of microelectronics. Digital ASIC's are
suited to medium to high levels of production where the non-recurrent engineering costs may be
recouped by production cost savings. The trend in digital ASICs is for faster clock speeds and low
power design techniques. Design complexities are rising as deep sub micron technologies
(nominally 0.18 micron and below) are continually being pushed by the semiconductor industry.
3. Analog Integrated Circuit (Analog IC)
While in many applications, large sections of analog circuitry have been replaced with their digital
counterparts, the need for analog circuit design is actually growing. Digital circuits need to be
interfaced with the analog world through filters and converters. However, analog implementations
are substantially manual pursuits.
4. Mixed Signal Integrated Circuits (Mixed Signal IC)
A mixed signal device is appropriate for small and medium sized chips (<250,000 transistors)
where a combination of analog and digital circuitry is integrated.
5. Radio Frequency Integrated Circuit (RF IC)
RF IC design covers the development of integrated wireless communication and signal processing
devices. Typical RF IC design involves a high frequency RF front-end and a lower frequency backend responsible for modulation and decoding of a signal. When systems become particularly large
or contain multiple technologies the term RF System-On-Chip (SOC) may be used such as the
wireless chip developed by the Radiata/CISCO team. RF devices have seen an explosive growth in
applications other than mobile phones as they allow for remote management and hand held
operation.
6. Microwave Monolithic Integrated Circuit (MMIC)
MMIC devices are a separate form of RF IC that tends to occupy the higher frequency end of the
spectrum. In general, MMIC circuits are low density (10's of transistors) and operate at high
frequency (1GHz) and above. At the lower end of their frequency range, MMIC devices can be
fabricated in standard silicon technologies while higher performance can be obtained by moving to
other chip substrates such as gallium arsenide (GaAs).
7. System-On-Chip (SOC)
SOC development is distinguished from traditional integrated devices by the marked increase in
system complexity and the integration of several technology domains. For example SOC designs
will incorporate traditional digital systems like microprocessors (which were once a chip in their own
right) with embedded memory and RF analog devices. In the future, mechanical, optical and
electro-biological systems will find their way in to SOC designs. SOC devices fall in to two main
categories:
•
•
Cost based SOC is characterized by large volume production directed at the consumer
electronics market. Systems are integrated on a chip to reduce manufacturing costs and
power consumption for hand held devices. A major emphasis for SOC is the reduction of
engineering development times through design re-use. This reduces time to market and
extends a product's life in an environment of decreasing product life cycles.
Performance based SOC is characterized by smaller volumes of high performance high
value products. These are commonly found in military, satellite and aerospace applications.
8. Bipolar Integrated Circuits
Bipolar integrated circuits have widespread applications in the power and automotive industries.
Their power sinking capability makes them more immune to switching spikes and inductive fly back
than CMOS technology. This has seen bipolar technology take an important role as an interface
between sensitive CMOS circuitry and harsh high voltage or mechanical environments.
9. Microsystems
Microsystems, also called MEMS, are small electrical and mechanical devices used for their
functionality in electrical systems as sensors and switches. MEMS applications range from on-chip
RF components such as antenna structures, to micro mirrors in optical systems. Current examples
of microsystems technology can be found in ink jet printer heads and in accelerometers for the
deployment of car airbags. The widespread application of microsystem devices gives them
enormous growth potential in medical applications for drug delivery, pathology products, sensors,
lab-on-chip for biology and optical devices. The microsystem product market is currently growing
by 20% to 25% annually.
10. Integrated Optoelectronic Devices
Optoelectronic devices include laser light sources, detectors, modulation devices, amplifiers,
multiplexers and demultiplexers. A large market for these chip integrated optical systems is in the
communications industry for applications such as switching devices and connectors.
<Wireless Communication> Messages, data, and signals are transmitted through space by
electric waves as a wireless message.
Rapid progresses in microelectronics result in the progress in wireless communication
technology.
Wireless communication evolution:
A cellular concept:
Wave propagation mechanisms: