ADS1220EVM Hardware Details
5
ADS1220EVM Hardware Details
The ADS1220EVM is designed to easily interface with other control platforms. Dual-row socket options
(JAC and JDB) are available on the bottom-side of the EVM, which allows for the controller connection.
The pin configuration of the connectors is designed to be compatible with LaunchPad. The connector
footprint conforms to Samtec™ connector SSW-110-22-F-D-VS-K, which is a dual-row, 20-pin, surface-
mount socket with a 0.1-inch pitch spacing.
Another method of controlling the ADS1220 is by connecting control signals to the test points for digital
communication to the ADS1220.
If using another controller other than the on-board MSP430, the control signals for this device must
become inoperative. To deactivate the on-board processor, short the JP5 pins, which places the output of
buffer U8 into a 3-state condition. Jumper JP5 is not installed by default. A wire can be soldered to the
terminals of JP5, or a standard 0.1-inch pitch header with shorting block can be installed.
5.1
Jumpers and Switches
Jumpers and switches function as shown in
.
Table 4. Jumper and Switch Descriptions
Jumper or
Functions
Descriptions
Switch
Short: Connect AIN0 (EXC+ of J1.4 and J6.4) to AVDD
JP1
EXC+ source
Open: AIN0 is not connected to AVDD (default)
Short: Connect AIN3 (EXC– of J1.1 and J6.1) to AGND
JP2
EXC– source
Open: AIN3 is not connected to AGND (default)
Short 1 to 2 (top): AVDD is connected to +5 V
JP3
Analog supply source
Short 3 to 4 (bottom): AVDD is connected to +3.3 V (default)
Short: External oscillator is used as the clock source (requires installation)
JP4
Clock source
Open: On-board or external (J8) clock source (default)
Short: External controller
JP5
Digital control source
Open: On-board controller
Short: Controller clock (not currently available)
JP6
External clock source
Open: Connected J8 clock source (default)
Short: Powered from the USB (default)
JP7
+5-V source
Open: +5 V supplied at J7 (also available at the JAC pin 2 and +5-V test
point)
Short: Regulated LDO on-board supply (default)
JP8
+3.3-V source
Open: Supplied externally at JAC or to +3.3-V test point
S1
Controller reset
Normally open SPST push-button resets controller on button press
Normally open SPST push-button enters controller bootstrap loader (BSL)
S2
Controller BSL
mode with button press while +3.3-V power is applied
5.2
Analog Headers, Terminal Blocks, and J3
For maximum flexibility, the ADS1220EVM is designed for easy interfacing to multiple analog sources.
These connectors provide access to the analog input pins of the ADS1220.
The EVM is designed to accept multiple sensor types. The sensor types can range from thermocouples,
resistance temperature detectors (RTDs), load cells, pressure, and so forth. The analog inputs can be
filtered by installing passive components in the optional filter circuitry. By default, the series input resistors
are populated with 0-
Ω
resistors and the capacitors are not installed. No circuitry is provided to buffer
these signals before connecting to the converter.
10
ADS1x20EVM
SBAU203 – July 2013
Copyright © 2013, Texas Instruments Incorporated