2-1
Analog Interface
Analog Interface
The ADS8381 analog-to-digital converter has both a positive and negative
analog input pin. Ground for the negative input is provided on the EVM (via
SJP3) close the device, or a user-furnished ground wire may be attached. The
negative input pin has a range of –200 mV up to 200 mV, and is shorted on the
EVM via SJP3. A signal for the positive input pin can be applied at connector
P1, pin 2 (shown in Table 2−1 ), or applied to the center pin of SMA connector
J2.
Table 2−1. Analog Input Connector
Description
Signal Name
Connector.Pin#
Signal Name
Description
Pin tied to Ground
AGND
P1.1
P1.2
+
Noninverting Input Channel
Reserved
N/A
P1.3
P1.4
N/A
Reserved
Reserved
N/A
P1.5
P1.6
N/A
Reserved
Reserved
N/A
P1.7
P1.8
N/A
Reserved
Pin tied to Ground
AGND
P1.9
P.10
N/A
Reserved
Pin tied to Ground
AGND
P1.11
P1.12
N/A
Reserved
Reserved
N/A
P1.13
P1.14
N/A
Reserved
Pin tied to Ground
AGND
P1.15
P1.16
N/A
Reserved
Pin tied to Ground
AGND
P1.17
P1.18
N/A
Reserved
Reserved
N/A
P1.19
P1.20
REF+
External Reference Input
Topic
Page
2.1
Signal Conditioning
2-2
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2.2
Reference
2-3
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Chapter 2