"DC precision is an
important spec for any
design that involves DC
measurement or a DC
set point. Without that
precision, system error
from the instrument
itself could jeopardize
the accuracy of the
intended applications."
Henry Fang
Electrical Hardware Engineer,
HORIBA Scientific
When designing precision narrow bandwidth signal chains, the focus is on the low frequency
specifications of the system. To achieve highly repeatable, high-quality measurement and
drive solutions, the signal chain must enable high accuracy, high stability, and high-resolution
readings. Historically, this pursuit can lead to design tradeoffs such as signal chain area, power
consumption, and complexity. As such, designing a high-precision DC signal chain relies heavily
on proper component selection to minimize the impact of detrimental tradeoffs.
When designing for precision narrow bandwidth applications, we
start with knowing our system goals, and then we can choose the
components that will allow us to get that level of performance. We first
focus on the most important parameters such as resolution, bandwidth,
and settling requirements, and from there build out our reference, analog
front end, and power trees to achieve the desired balance between
system performance and acceptable tradeoffs.
Ryan Curran
ADC Product Marketing Manager at ADI
The design process starts by identifying the overall application and system performance goals;
choosing the correct converter solution (ADC and/or DAC) for the job; and then tightly coupling
the proper amplifier, reference, switch, isolation, and digital host (e.g., MCU) components to
meet the system requirements.
14 | Optimizing for Highest DC Precision
