Texas Instruments ADS1x20EVM, User Manual, Page: 11 / 24

www.ti.com
ADS1220EVM Hardware Details
5.2.1 Primary Analog Interface, J4
All available analog pins of the ADS1220 connect to header J4. J4 can be used to connect analog signals
from off-board sensors or sources to the ADS1220.
Table 5 provides J4 pin descriptions. J4 is a standard
10-pin, dual-row header, with 0.1-inch pin spacing.
Table 5. J4: Primary Analog Interface Pinout
Description Signal Pin Number
Analog dedicated reference input, negative REFN0 J4.9
Analog dedicated reference input, positive REFP0 J4.10
AGND J4.1
(1)
AGND J4.3
Analog ground
AGND J4.5
AGND J4.7
Analog input channel 1 AIN0/REFP1 J4.2
Analog input channel 2 AIN1 J4.4
Analog input channel 3 AIN2 J4.6
Analog input channel 4 AIN3/REFN1 J4.8
(1)
Pin 1 is at the top left-hand corner, located opposite of the reference designator.
5.2.2 Bridge Sensor Connectors, J1 and J6
Connectors J1 and J6 are designed to be used with bridge sensor applications. J1 is a four-position screw
terminal block that can accept wire sizes AWG 28-16. J6 is a standard single-row, 4-pin header with 0.1-
inch pin spacing. Both connectors allow for excitation to be connected to the outer pins while the
differential signals from the sensor connect to the inner pins.
Table 6 lists pin descriptions.
Bridge excitation is provided from the analog supply as needed. JP1 connects EXC+ directly to AVDD.
JP2 connects EXC– directly to AGND. To conserve power, EXC– can also be connected to AGND
through the low-side switch of the ADS1220.
Table 6. J1 and J6: Bridge Sensor Connectors
Description Signal Pin Number
Analog input, negative (IN–) AIN2 J1.2 or J6.2
Analog input, positive (IN+) AIN1 J1.3 or J6.3
AIN3/REFN1 J1.1
(2)
or J6.1
(2)
Bridge excitation, negative (EXC–)
(1)
Negative reference input for ratiometric measurement (REFN1)
AIN0/REFP1 J1.4 or J6.4
Bridge excitation, positive (EXC+)
(3)
Positive reference input for ratiometric measurement (REFP1)
(1)
EXC– can be connected to AGND through JP2, or through the low-side switch of AIN3/REFN1 of the ADS1220.
(2)
Pin 1 is at the top right-hand corner, located next to the reference designator.
(3)
EXC+ can be connected to AVDD through JP1.
11 SBAU203 – July 2013 ADS1x20EVM
Submit Documentation Feedback
Copyright © 2013, Texas Instruments Incorporated