Volume 39, Number 2, April -
Issue as PDF
ADC Architecture Is Right For Your Application?
Selecting the proper ADC for a particular application can be a formidable task,
considering the thousands of available converters. An understanding of three
popular architectures—successive-approximation, sigma-delta,
and pipelined—and their relationship to the data acquisition,
precision measurement, audio, and high speed markets is a
useful supplement to selection guides and search engines.
Pushing the State of the Art with Multichannel A/D Converters
demanding data-acquisition requirements surpass the performance levels provided
by commercially available integrated-circuit ADCs. Innovative solutions that
fulfill high-end data-acquisition system needs while awaiting the next
performance breakthrough use signal averaging, for increased resolution
without loss of speed—and time interleaving, to increase sampling rates
without loss of resolution.
Transformer-Coupled Front-End for
Wideband A/D Converters
ADCs are being
used at ever higher frequencies, making receiver front-end design increasingly
important. Many applications are moving to super-Nyquist sampling in order to
eliminate a mix-down stage, but amplifier noise will degrade the signal-to-noise
ratio at these frequencies. Transformers can be used to replace the amplifier,
minimizing noise and providing good high-frequency coupling.