JAJSPC7A December 2022 – August 2023 ADS131B23
PRODUCTION DATA
The ADS131B23 integrates many monitor and diagnostic circuits to aid in the design of functional safety systems. Monitors detect faults in the device, such as a supply undervoltage condition, whereas diagnostics detect faults within the monitoring circuit to check if the monitor is still working as intended.
Table 8-14 provides an overview of all available monitors and diagnostics. Most monitors can be enabled or disabled as required using a dedicated monitor enable bit. If a monitor detects a fault, the according low-active fault flag is set to 0b. Except for the communication-related monitor fault flags, the fault flags must be cleared to 1b by the host after the fault condition is removed. The communication-related monitor fault flags reset to 1b automatically in the SPI frame following a frame where no communication fault occurred.
The monitors that have a dedicated diagnostic circuit to check the integrity of the monitor show the respective diagnostic enable bit in Table 8-14.
The monitors have individual fault response times, which is the time from fault occurrence to fault flag indication, as specified in the Electrical Characteristics table.
MONITOR NAME | MONITOR ENABLE BIT | MONITOR FAULT FLAG | DIAGNOSTIC ENABLE BIT | FAULT FLAG REGISTER LOCATION |
---|---|---|---|---|
SUPPLY MONITORS AND DIAGNOSTICS | ||||
Reset | N/A | RESETn | N/A | STATUS_MSB |
AVDD overvoltage | AVDD_OV_EN | AVDD_OVn | AVDD_OV_DIAG_EN | SUPPLY_STATUS |
AVDD undervoltage | AVDD_UV_EN | AVDD_UVn | AVDD_UV_DIAG_EN | SUPPLY_STATUS |
IOVDD overvoltage | IOVDD_OV_EN | IOVDD_OVn | IOVDD_OV_DIAG_EN | SUPPLY_STATUS |
IOVDD undervoltage | IOVDD_UV_EN | IOVDD_UVn | IOVDD_UV_DIAG_EN | SUPPLY_STATUS |
DVDD overvoltage | DVDD_OV_EN | DVDD_OVn | DVDD_OV_DIAG_EN | SUPPLY_STATUS |
DVDD undervoltage | DVDD_UV_EN | DVDD_UVn | DVDD_UV_DIAG_EN | SUPPLY_STATUS |
AVDD oscillation | AVDD_OSC_EN | AVDD_OSCn | AVDD_OSC_DIAG_EN | SUPPLY_STATUS |
IOVDD oscillation | IOVDD_OSC_EN | IOVDD_OSCn | IOVDD_OSC_DIAG_EN | SUPPLY_STATUS |
DVDD oscillation | DVDD_OSC_EN | DVDD_OSCn | DVDD_OSC_DIAG_EN | SUPPLY_STATUS |
AVDD LDO overtemperature warning | AVDD_OTW_EN | AVDD_OTWn | N/A | SUPPLY_STATUS |
IOVDD LDO overtemperature warning | IOVDD_OTW_EN | IOVDD_OTWn | N/A | SUPPLY_STATUS |
AVDD LDO output current limit | AVDD_CL_EN | AVDD_CLn | N/A | SUPPLY_STATUS |
IOVDD LDO output current limit | IOVDD_CL_EN | IOVDD_CLn | N/A | SUPPLY_STATUS |
AGNDA pin disconnect | AGNDA_DISC_EN | AGNDA_DISCn | AGNDA_DISC_DIAG_EN | SUPPLY_STATUS |
AGNDB pin disconnect | AGNDB_DISC_EN | AGNDB_DISCn | AGNDB_DISC_DIAG_EN | SUPPLY_STATUS |
DGND pin disconnect | DGND_DISC_EN | DGND_DISCn | DGND_DISC_DIAG_EN | SUPPLY_STATUS |
CLOCK MONITORS AND DIAGNOSTICS | ||||
Main clock frequency | MCLK_MON_EN | MCLK_FAULTn | MCLK_HI_DIAG_EN, MCLK_LO_DIAG_EN | CLOCK_STATUS |
Diagnostic oscillator watchdog | OSCD_WD_EN | OSCD_WDn | OSCD_WD_DIAG_EN | CLOCK_STATUS |
Main clock watchdog | MCLK_WD_EN | MCLK_WDn | MCLK_WD_DIAG_EN | CLOCK_STATUS |
DIGITAL MONITORS AND DIAGNOSTICS | ||||
Register map section 1 CRC | REG_MAP1_CRC_EN | REG_MAP1_CRC_FAULTn | N/A | DIGITAL_STATUS |
Register map section 2 CRC | REG_MAP2_CRC_EN | REG_MAP2_CRC_FAULTn | N/A | DIGITAL_STATUS |
Register map section 3 CRC | REG_MAP3_CRC_EN | REG_MAP3_CRC_FAULTn | N/A | DIGITAL_STATUS |
Memory map CRC | N/A | MEM_MAP_CRC_FAULTn | MEM_MAP_CRC_DIAG[1:0] | DIGITAL_STATUS |
GPIOA readback | N/A | N/A | GPIOA_DIAG_EN | GPIA_GPIB_DATA |
GPIOB readback | N/A | N/A | GPIOB_DIAG_EN | GPIA_GPIB_DATA |
GPIO readback | N/A | N/A | GPIO_DIAG_EN | GPI_DATA |
COMMUNICATION MONITORS AND DIAGNOSTICS | ||||
SPI CRC | N/A | SPI_CRC_FAULTn | N/A | STATUS_MSB |
SPI timeout | TIMEOUT_EN | SPI_TIMEOUTn | N/A | STATUS_MSB |
SCLK counter | SCLK_COUNTER_EN | SCLK_COUNT_FAULTn | N/A | STATUS_MSB |
Register access | N/A | REG_ACCESS_FAULTn | N/A | STATUS_MSB |
In addition to the monitors that detect faults in the device, the ADS131B23 also provides the indicators shown in Table 8-15, which provides feedback about the device state or behavior.
INDICATOR NAME | INDICATOR STATUS BIT | STATUS BIT REGISTER LOCATION |
---|---|---|
Command response | COMMAND_RESPONSE[3:0] | STATUS_MSB |
Lock state | LOCK | STATUS_MSB |
Clock source | CLOCK | STATUS_MSB |
Operating mode | MODE | STATUS_MSB |
ADC2A sequence active | SEQ2A_ACTIVE | STATUS_LSB |
OTP bank | OTB_BANK | DIGITAL_STATUS |
Lastly, the device provides the conversion and sequence counters shown in Table 8-16 for the individual ADCs.
COUNTER NAME | COUNTER BITS | COUNTER BITS REGISTER LOCATION |
---|---|---|
ADC1A conversion counter | CONV1A_COUNT[1:0] | STATUS_LSB |
ADC1B conversion counter | CONV1B_COUNT[1:0] | STATUS_LSB |
ADC2A sequencer counter | SEQ2A_COUNT[1:0] | STATUS_LSB |
Besides the monitors, indicators, and counters mentioned in the previous tables, the ADS131B23 offers additional means to check the integrity of the device, such as: