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Did you know I've got a l33t motherf---ing geek in the family? He's
finishing up his Masters and will get a Doctorate in EE. I've always
believed that if not for the efforts of a tiny percentage of the
population humanity would still be living in grass huts.
From my np brother:
"""
what the hell am I doing?
I thought I would write about what I study and research as it's a very
esoteric field but may be interesting to some of you. Or if it's not
interesting to you, at least you'll have something to say when someone
asks you what I do. I'll try to avoid the minutiae of the subject while
still giving you some tangible information.
I study Sigma-delta data converters. Sigma-delta is a specific type of
architecture that works well for 16 to 24-bit applications like audio.
A data converter is a specific type of integrated circuit (IC) that
converts analog signals to or from digital signals.
Analog signals are voltages or currents that represent "real-world"
signals. Two examples are:
(1) the current on a speaker wire that represents the desired acoustic
output of the speaker
(2) the voltage driving a transmitting radio antenna the represents the
desired electro-magnetic radiation
Digital signals are 1's and 0's that can be processed by a computer.
In short, analog signals are a necessary evil and digital signals offer
some attractive benefits (e.g. robust manipulation, compact storage,
accurate duplication). Data converters then exist at the boundary of
the real-world and the digital world.
For example, an analog-to-digital converter (ADC) can take the voltage
signal from a microphone on a cell phone and convert it to a digital
format so that it can be transmitted. Likewise, a digital-to-analog
converter (DAC) can take the digital signal the cell phone receives and
convert it into a current signal that can drive the speaker.
The big areas of research in this field are (1) lower power and (2)
migrating technologies. The desire for lower power is easy to
understand: lower power = more battery life in a portable device.
Analog circuits usually consume more power than digital circuits so good
research in this area can be lucrative.
Migrating technologies refers to the changing transistor dimensions.
This is what the terms 90nm, 65nm, 45nm (nm = nanometer) mean. Cost in
the IC business is proportional to area. So, there's a big push from
the "digital circuits people" for smaller transistors and newer
technologies. These smaller transistors make analog design very
difficult and new, innovative techniques are required at each technology
node to maintain the performance of the previous generation.
My research is looking at replacing some very complex analog circuits
inside a sigma-delta ADC with "digital-like" circuits that produce the
same function.
In my opinon, data converter design is one the most difficult aspects of
IC design. A good designer has to know analog circuits, digital
circuits, signal-processing, and sensors/transducers. And as long as
innovative designs are required, there will be good jobs for high
quality engineers.
End transmission.
"""
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