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dc2581af
DEMO MANUAL DC2581A
DC2581A SETUP
Layout
As with any high performance ADC, this part is sensitive
to layout. The area immediately surrounding the ADC on
the DC2581A should be used as a guideline for placement,
and routing of the various components associated with
the ADC. Here are some things to remember when laying
out a board for the LTC2341. A ground plane is necessary
to obtain maximum performance. Keep bypass capacitors
as close to supply pins as possible. Use individual low
impedance returns for all bypass capacitors. Use of a
symmetrical layout around the analog inputs will minimize
the effects of parasitic elements. Shield analog input traces
with ground to minimize coupling from other traces. Keep
traces as short as possible.
Component Selection
When driving a low noise, low distortion ADC such as the
LTC2341, component selection is important so as to not
degrade performance. Resistors should have low values
to minimize noise and distortion. Metal film resistors are
recommended to reduce distortion caused by self heat-
ing. Because of their low voltage coefficients, to further
reduce distortion NPO or silver mica capacitors should be
used. Any buffer used to drive the LTC2341 should have
low distortion, low noise and a fast settling time such as
the LT6237.