INTRODUCTION
Process control technology has developed and adapted
from its earliest form of single channel, analog control
loops, to enormously complex, multiple parameter control
systems. High performance microprocessors are the heart
of such systems, and it is assumed that sheer processor
speed alone will determine the overall control loop
bandwidth and response time of the system. However, the
“number crunching” power of such processors cannot
effectively be optimized until the process control
parameters are accurately digitized using proper
conversion techniques within the requirements of the
control loop response. To further complicate the design
process, restrictions such as single supply operation and
low power consumption may be imposed.

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