AD571
with the 2 control bits (which act as outputs), are used to con-
trol the 8 AD571s. When a control line is in the “1” or high
state, the ADC will be automatically blanked. That is, its out-
puts will be in the inactive open state. If a single control line is
switched low, its ADC will convert and the outputs will auto-
matically go active when the conversion is complete. The result
can then be read from the two peripheral ports; when the next
conversion is desired, a different control line can be switched to
zero, blanking the previously active port at the same time. Sub-
sequently, this second device can be read by the microprocessor,
and so-forth. The status lines are wire-ored in 2 groups and
connected to the two remaining control pins. This allows a con-
version status check to be made after a convert command, if
necessary. The ADCs are divided into two groups to minimize
the loading effect of the internal pull-up resistors on the
DATA
READY
buffers.
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
18-Lead Ceramic Dual-In-Line Package
–8–
REV. A
PRINTED IN U.S.A.
C457d–4–1/87
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