Texas Instruments ADS1235EVM, Руководство пользователя

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Hardware Reference
9 SBAU293 – March 2018
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ADS1261 and ADS1235 Evaluation Module
ADVANCE INFORMATION
3.2.3 Digital Interface Header
Table 5 lists the functions and pin numbers for all signals used on the digital interface.
(1)
Even-numbered pins not included in this list are connected to GND.
(2)
Odd-numbered pins not included are connected to the Tiva microcontroller (after passing through level shifters) but the
functionality is not used for this EVM. For connection details, see
Figure 16 .
(3)
Signals connected to the Tiva microcontroller are named according to their respective processor pin connections. For connection
details, see
Figure 16 .
Table 5. Digital Interface, J6
Function ADC Side Processor Side
Signal Name Pin Number
(1)
Pin Number
(2)
Signal Name , Tiva
Connection
(3)
External voltage input GND 56 55 EXT_5V
Bank3 level-shifter voltage DVDD 54 53 LVDD1
GPIO for ADC FAULT_LED 52 51 PD7
EXT_CLK 42 41 PD3 (Unused)
Bank2 level-shifter voltage DVDD 36 35 LVDD2
ADC GPIO ADC_nPWDN 34 33 PA0
SPI0 ADC_nDRDY 32 31 PA1
ADC_SCLK 30 29 PA2 (SSI0CLK)
ADC_nCS 28 27 PA3
ADC_MOSI (DIN) 26 25 PA4 (SSI0XDAT0)
ADC_MISO (DOUT) 24 23 PA5 (SSI0XDAT1)
ADC GPIOs ADC_START 22 21 PA6
ADC_nRESET 20 19 PA7
Bank1 level-shifter voltage DVDD 18 17 LVDD3 (Unused)
3.2.4 Test Points
The test points listed in Table 6 may be used to probe onboard voltage supplies and signals.
Table 6. Useful Test Points
Function Signal Name Restrictions
ADC side
Analog input (ADS1261EVM: AIN9) A9 Probe only
Analog input (ADS1261EVM: AIN8) A8 Probe only
Analog input (ADS1261EVM: AIN7, ADS1235EVM: AIN5) A7 Probe only
Analog input (ADS1261EVM: AIN6, ADS1235EVM: AIN4) A6 Probe only
Analog input (ADS1261EVM: AIN5, ADS1235EVM: AIN3) A5 Probe only
Analog input (ADS1261EVM: AIN4, ADS1235EVM: AIN2) A4 Probe only
Analog input (ADS1261EVM: AIN3, ADS1235EVM: AIN1) A3 Probe only
Analog input (ADS1261EVM: AIN2, ADS1235EVM: AIN0) A2 Probe only
Analog input (ADS1261EVM: AIN1, ADS1235EVM: REFN0) A1 Probe only
Analog input (ADS1261EVM: AIN0, ADS1235EVM, REFP0) A0 Probe only
Analog input (ADS1261EVM: AINCOM) A10 Probe only
External Bridge Supply (EXC+ positive supply) AVDD/EXC+ Remove R6 before connecting to an external
supply, consider the common mode voltage of
the ADC when selecting EXC+ voltage
External Bridge Supply (AVSS "ground" reference) AVDD For external supply ground reference only. Do
not apply a voltage to this testpoint.
External Bridge Supply (EXC– negative supply) AVSS/EXC– Remove R25 before connecting to external
supply, consider the common mode voltage of
the ADC when selecting EXC– voltage