Texas Instruments ADS1x15V2EVM-PDK, Руководство пользователя

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3.2 Digital Interface
As noted in Section 3.1 , the ADS1x15 interfaces with the PAMBoard and the PAMBoard communicates with
the computer over USB. The two devices on the EVM requiring communication are the ADS1x15 ADC (U1)
and the electrically erasable programmable read-only memory (EEPROM) (U3) using I
2
C (see Figure 6-5 ). The
EEPROM is preprogrammed with the information required to configure and initialize the ADS1x15V2EVM-PDK
GUI software platform. When the hardware is initialized through the software, the EEPROM is no longer used.
The PAMBoard and EEPROM (U3) use 3.3 V for the device interface logic levels. The ADS1x15 can operate at
either 3.3 V or 5 V as desired by jumper selection JP1. To allow the ADS1x15 to operate at 5-V logic levels, a
logic level translator (U2) is used.
3.3 Analog Input Connections
The ADS1x15 device is designed for easy interface to an external sensor that is differential or single-ended
using either a header (J6) or a screw terminal block (J5). Connector J6 provides an easy interface connection for
differential input pairs with each pair separated by analog ground.
Table 3-2 lists the channel input connections
for J5 and Table 3-3 shows the input connections for J6. Both connectors are clearly labeled on the PCB
silkscreen for easy input connection identification.
Table 3-2. Terminal Block Input (J5)
J5 Terminal Block Inputs Description
J5:1 Analog input for AIN0 of the ADC
J5:2 Analog input for AIN1 of the ADC
J5:3 Analog input for AIN2 of the ADC
J5:4 Analog input for AIN3 of the ADC
J5:5 Analog ground
Table 3-3. Terminal Block Input (J6)
J6 Terminal Block Inputs Description
J6:1 Analog input for AIN0 of the ADC
J6:2 Analog input for AIN1 of the ADC
J6:3 and J6:4 Analog ground
J6:5 Analog input for AIN2 of the ADC
J6:6 Analog input for AIN3 of the ADC
Connector J5 is a screw terminal block for attaching an external sensor with bare wire connections. The terminal
block includes all four inputs and a connection point for analog ground.
Figure 3-2 shows the input layout.
Figure 3-2. Analog Input Terminal Block (J5)
Connector J6 is a 100-mil spaced dual-row header. Jumper wire or clip leads can be used for connections. The
header includes all four inputs and two analog ground connections.
Figure 3-3 shows the input layout.
Figure 3-3. Analog Input Header (J6)
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SBAU362 – MARCH 2021
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ADS1x15V2EVM-PDK User's Guide 9
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