Information
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PmodAD2™ Reference Manual
Revised May 24, 2016
This manual applies to the PmodAD2 rev. A
DOC#: 502-217
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
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Overview
The PmodAD2 is an analog-to-digital converter powered by the Analog Devices AD7991. Users may communicate
with the board through I
2
C to configure up to 4 conversion channels at 12 bits of resolution.
1 Functional Description
The PmodAD2 utilizes Analog Devices® AD7991 to provide up to four channels of 12-bit analog-to-digital
conversion.
2 Interfacing with the Pmod
The PmodAD2 communicates with the host board via the I²C protocol. System boards are able to call the Pmod by
sending out the device address of 0b0101000 followed by the appropriate read or write bit. If a write bit is chosen,
users may then configure the on-board chip to only use certain channels or may immediately start reading the 12
bits of data from the 16-bit data register if the read bit is sent.
Unlike other devices that use I²C, no addresses are associated with these two registers; only the read/write bit at
the end of the slave address distinguishes between the two registers. By default, all four channels have analog-to-
The PmodAD2.
Up to four 12-bit analog to digital converter
channels
On-board 2.048 V voltage reference
Jumper selectable reference input
Small PCB size for flexible designs (1.0 in × 0.8
in)(2.5 cm × 2.0 cm)
Follows Digilent Interface Specification
Library and example code available in resource
center
Features include: