SLASEU7 March   2023 AFE781H1 , AFE881H1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics
    6. 6.6  Timing Requirements
    7. 6.7  Timing Diagrams
    8. 6.8  Typical Characteristics: VOUT DAC
    9. 6.9  Typical Characteristics: ADC
    10. 6.10 Typical Characteristics: Reference
    11. 6.11 Typical Characteristics: HART Modem
    12. 6.12 Typical Characteristics: Power Supply
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Digital-to-Analog Converter (DAC) Overview
        1. 7.3.1.1 DAC Resistor String
        2. 7.3.1.2 DAC Buffer Amplifier
        3. 7.3.1.3 DAC Transfer Function
        4. 7.3.1.4 DAC Gain and Offset Calibration
        5. 7.3.1.5 Programmable Slew Rate
        6. 7.3.1.6 DAC Register Structure and CLEAR State
      2. 7.3.2 Analog-to-Digital Converter (ADC) Overview
        1. 7.3.2.1 ADC Operation
        2. 7.3.2.2 ADC Custom Channel Sequencer
        3. 7.3.2.3 ADC Synchronization
        4. 7.3.2.4 ADC Offset Calibration
        5. 7.3.2.5 External Monitoring Inputs
        6. 7.3.2.6 Temperature Sensor
        7. 7.3.2.7 Self-Diagnostic Multiplexer
        8. 7.3.2.8 ADC Bypass
      3. 7.3.3 Programmable Out-of-Range Alarms
        1. 7.3.3.1 Alarm-Based Interrupts
        2. 7.3.3.2 Alarm Action Configuration Register
        3. 7.3.3.3 Alarm Voltage Generator
        4. 7.3.3.4 Temperature Sensor Alarm Function
        5. 7.3.3.5 Internal Reference Alarm Function
        6. 7.3.3.6 ADC Alarm Function
        7. 7.3.3.7 Fault Detection
      4. 7.3.4 IRQ
      5. 7.3.5 HART Interface
        1. 7.3.5.1  FIFO Buffers
          1. 7.3.5.1.1 FIFO Buffer Access
          2. 7.3.5.1.2 FIFO Buffer Flags
        2. 7.3.5.2  HART Modulator
        3. 7.3.5.3  HART Demodulator
        4. 7.3.5.4  HART Modem Modes
          1. 7.3.5.4.1 Half-Duplex Mode
          2. 7.3.5.4.2 Full-Duplex Mode
        5. 7.3.5.5  HART Modulation and Demodulation Arbitration
          1. 7.3.5.5.1 HART Receive Mode
          2. 7.3.5.5.2 HART Transmit Mode
        6. 7.3.5.6  HART Modulator Timing and Preamble Requirements
        7. 7.3.5.7  HART Demodulator Timing and Preamble Requirements
        8. 7.3.5.8  IRQ Configuration for HART Communication
        9. 7.3.5.9  HART Communication Using the SPI
        10. 7.3.5.10 HART Communication Using UART
        11. 7.3.5.11 Memory Built-In Self-Test (MBIST)
      6. 7.3.6 Internal Reference
      7. 7.3.7 Integrated Precision Oscillator
      8. 7.3.8 One-Time Programmable (OTP) Memory
    4. 7.4 Device Functional Modes
      1. 7.4.1 DAC Power-Down Mode
      2. 7.4.2 Reset
    5. 7.5 Programming
      1. 7.5.1 Communication Setup
        1. 7.5.1.1 SPI Mode
        2. 7.5.1.2 UART Mode
        3. 7.5.1.3 SPI Plus UART Mode
        4. 7.5.1.4 HART Functionality Setup Options
      2. 7.5.2 Serial Peripheral Interface (SPI)
        1. 7.5.2.1 SPI Frame Definition
        2. 7.5.2.2 SPI Read and Write
        3. 7.5.2.3 Frame Error Checking
        4. 7.5.2.4 Synchronization
      3. 7.5.3 UART Interface
        1. 7.5.3.1 UART Break Mode (UBM)
          1. 7.5.3.1.1 Interface With FIFO Buffers and Register Map
      4. 7.5.4 Status Bits
      5. 7.5.5 Watchdog Timer
    6. 7.6 Register Maps
      1. 7.6.1 AFEx81H1 Registers
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Multichannel Configuration
    2. 8.2 Typical Application
      1. 8.2.1 4-mA to 20-mA Current Transmitter
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Start-Up Circuit
          2. 8.2.1.2.2 Current Loop Control
          3. 8.2.1.2.3 Input Protection and Rectification
          4. 8.2.1.2.4 System Current Budget
        3. 8.2.1.3 Application Curves
    3. 8.3 Initialization Set Up
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  9. Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

AFEx81H1 Registers

Complex bit access types are encoded to fit into small table cells. The following table shows the codes that are used for access types in this section.

Table 7-14 AFEx81H1 Access-Type Codes
Access Type Code Description
Read Type
R R Read
Write Type
W W Write
W WO Write only
W WSC Write self clear
Reset or Default Value
-n Value after reset or the default value
Register Array Variables
i,j,k,l,m,n When used in a register name, an offset, or an address, these variables refer to the value of a register array where the register is part of a group of repeating registers. The register groups form a hierarchical structure and the array is represented with a formula.
y When used in a register name, an offset, or an address, this variable refers to the value of a register array.

7.6.1.1 NOP Register (Offset = 0h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-15 NOP Register Field Descriptions
Bit Field Type Reset Description
15-0 NOP WO 0h No operation. Data written to this field have no effect. Always reads zeros.

7.6.1.2 DAC_DATA Register (Offset = 1h) [Reset = 0000h]

Return to the Table 7-13.

DAC code for VOUT.

Table 7-16 DAC_DATA Register Field Descriptions
Bit Field Type Reset Description
15-0 DATA R/W 0h Data.
DAC code for VOUT.

7.6.1.3 CONFIG Register (Offset = 2h) [Reset = 0036h]

Return to the Table 7-13.

Table 7-17 CONFIG Register Field Descriptions
Bit Field Type Reset Description
15 RESERVED R 0h
14-13 CRC_ERR_CNT R/W 0h CRC Errors Count Limit

Sets the numbers of consecutive SPI CRC frames that must have errors before the status bits is set.

0h = 1 (default); 1h = 2; 2h = 4; 3h = 8

12 CLKO_DIV R/W 0h CLKO Divider
Divide the clock by 128 to output to CLKO.

0h = Divider disabled, output 1.2288 MHz (default)

1h = Divider enabled, output 9600 Hz

11 CLKO_EN R/W 0h CLKO Enable
Enable the internal oscillator to be driven on CLKO pin.

0h = Disabled (default); 1h = Enabled

10 RESERVED R 0h
9 UBM_IRQ_EN R/W 0h UBM IRQ Enable
Enable IRQ to be sent on UARTOUT through UBM.

0h = Disabled (default); 1h = Enabled

8 IRQ_PIN_EN R/W 0h IRQ Pin Enable
Enable IRQ pin functionality.

0h = Disabled (default); 1h = Enabled

7 CLR_PIN_EN R/W 0h Clear Input Pin Enable
Enable pin-based transition to the CLEAR state in UBM.

0h = Disabled (default); 1h = SDI pin configured as clear input pin

6 UART_DIS R/W 0h UART Disable
Disable UART functionality.

0h = Disabled (default); 1h = Enabled

5 UART_BAUD R/W 1h UART Baud
Configure BAUD rate for UART.

0h = 1200 baud (no Break)

1h = 9600 baud (Break Mode) (default)

4 CRC_EN R/W 1h CRC Enable
Enable CRC for SPI.

0h = Disabled; 1h = Enabled (default)

3 IRQ_POL R/W 0h IRQ Polarity

0h = Active low (default); 1h = Active high

2 IRQ_LVL R/W 1h IRQ Level

0h = Edge sensitive

1h = Level sensitive (default)

1 DSDO R/W 1h SDO Hi-Z

0h = Drive SDO during CS = 0

1h = SDO always Hi-Z (default)

0 FSDO R/W 0h Fast SDO
SDO is driven on negative edge of SCLK.

0h = drive SDO on rising edge of SCLK (launching edge) (default)

1h = drive SDO on falling edge of SCLK (capture edge 1/2 clock early)

7.6.1.4 DAC_CFG Register (Offset = 3h) [Reset = 0B00h]

Return to the Table 7-13.

Table 7-18 DAC_CFG Register Field Descriptions
Bit Field Type Reset Description
15-13 RESERVED R/W 0h
12 PD R/W 0h DAC Output Buffer Power-down

DAC output set to Hi-Z in power-down.

0h = DAC output buffer enabled (default)

1h = DAC output buffer disabled

11-9 SR_CLK R/W 5h Slew Clock Rate

0h = 307.2 kHz

1h = 153.6 kHz

2h = 76.8 kHz

3h = 38.4 kHz

4h = 19.2 kHz

5h = 9600 Hz (default)

6h = 4800 Hz

7h = 2400 Hz

8-6 SR_STEP R/W 4h Slew Step Size

0h = 1 code

1h = 2 codes

2h = 4 codes

3h = 8 codes

4h = 16 codes (default)

5h = 32 codes

6h = 64 codes

7h = 128 codes

5 SR_EN R/W 0h Slew Enable

Enables slew on the output voltage.

0h = Disabled (default)

1h = Enabled

4 SR_MODE R/W 0h Slew Mode

Output slew rate mode select.

0h = Linear Slew (default)

1h = Sinusoidal Slew

3 RESERVED R 0h
2 CLR R/W 0h CLEAR State

0h = Normal operation (default)

1h = Force the DAC to the CLEAR state

1 CLR_RANGE R/W 0h Clear Range
Sets DAC CLEAR state output range.

0h = 0.15 V to 1.25 V (default)

1h = 0.2 V to 1.0 V

0 RANGE R/W 0h Range
Sets DAC output range during normal operation.

0h = 0.15 V to 1.25 V (default)

1h = 0.2 V to 1.0 V

7.6.1.5 DAC_GAIN Register (Offset = 4h) [Reset = 8000h]

Return to the Table 7-13.

Table 7-19 DAC_GAIN Register Field Descriptions
Bit Field Type Reset Description
15-0 GAIN R/W 8000h Gain
Set the gain of the DAC output from 0.5 – 1.499985.
For example:

0000h = 0.5

8000h = 1.0 (default)

FFFFh = 1.499985

7.6.1.6 DAC_OFFSET Register (Offset = 5h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-20 DAC_OFFSET Register Field Descriptions
Bit Field Type Reset Description
15-0 OFFSET R/W 0h Offset
Adjust the offset of the DAC output, 2's complement number.
For example:

0000h = 0 (default)

FFFFh = –1

7.6.1.7 DAC_CLR_CODE Register (Offset = 6h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-21 DAC_CLR_CODE Register Field Descriptions
Bit Field Type Reset Description
15-0 CODE R/W 0h CLEAR State DAC Code
DAC code applied in the CLEAR state. See Section 7.3.1.6.

7.6.1.8 RESET Register (Offset = 7h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-22 RESET Register Field Descriptions
Bit Field Type Reset Description
15-8 RESERVED R 0h
7-0 SW_RST WSC 0h

Software Reset

Write ADh to initiate software reset.

7.6.1.9 ADC_CFG Register (Offset = 8h) [Reset = 8810h]

Return to the Table 7-13.

Table 7-23 ADC_CFG Register Field Descriptions
Bit Field Type Reset Description
15 BUF_PD R/W 1h ADC Buffer Power-down

0h = ADC buffer enabled; 1h = ADC buffer powered down (default)

14-8 HYST R/W 8h Hysteresis
The number of codes of hysteresis used when a threshold is exceeded for an ADC measurement of AIN0/AIN1/TEMP.
7-5 FLT_CNT R/W 0h Fault Count
Number of successive faults to trip an alarm.
Number of successive faults is programmed value + 1 (1-8 faults).
4 AIN_RANGE R/W 1h ADC Analog Input Range

Can only be set if PVDD ≥ 2.7 V to use 2.5-V range for AIN0 and AIN1 inputs.

0h = 2 × VREF; 1h = 1 × VREF (default)

3 EOC_PER_CH R/W 0h ADC End-of-Conversion for Every Channel
Sends an EOC pulse at the end of each channel instead of at the end of all the channels.

0h = EOC after last channel (default); 1h = EOC for every channel

2-1 CONV_RATE R/W 0h ADC Conversion Rate
This setting only affects the conversion rate for channels AIN0 and AIN1. Rates are based on a 76.8-kHz ADC clock. All other channels use 2560 Hz.

0h = 3840 Hz (default)

1h = 2560 Hz

2h = 1280 Hz

3h = 640 Hz

0 DIRECT_MODE R/W 0h Direct Mode Enable

0h = Auto mode (default); 1h = Direct mode

7.6.1.10 ADC_INDEX_CFG Register (Offset = 9h) [Reset = 0080h]

Return to the Table 7-13.

The ADC custom channel sequencing configuration is shown in Table 7-24.

Table 7-24 ADC_INDEX_CFG Register Field Descriptions
Bit Field Type Reset Description
15-8 RESERVED R 0h
7-4 STOP R/W 8h Custom Channel Sequencer Stop Index
CCS index to stop ADC sequence. Must be ≥ START. If not, STOP is forced to = START.

0h = OFFSET

1h = AIN0

2h = AIN1

3h = TEMP

4h = SD0 (VREF)

5h = SD1 (PVDD)

6h = SD2 (VDD)

7h = SD3 (ZTAT)

8h = SD4 (VOUT) (default)

9h through Fh = GND

3-0 START R/W 0h Custom Channel Sequencer Start Index
CCS index to start ADC sequence.

0h through Fh = Same as STOP field (0h is default)

7.6.1.11 TRIGGER Register (Offset = Ah) [Reset = 0000h]

Return to the Table 7-13.

Table 7-25 TRIGGER Register Field Descriptions
Bit Field Type Reset Description
15-3 RESERVED R 0h
2 MBIST WSC 0h Memory Built-In Self-Test Trigger

This trigger initiates an MBIST on the SRAM that is used for the FIFO. During this time communication to/from HART does not work as MBIST takes over the control of the SRAM.

1 SHADOWLOAD WSC 0h Shadowload Trigger
This trigger initiates the loading of the OTP array into the parallel latches. If an OTP CRC error is detected, assert this trigger to try and reload the OTP into the memory locations.
0 ADC WSC 0h ADC Trigger
In auto mode, this bit enables or disables the conversions. Manually set 1 (enable) and 0 (disable). In direct mode, setting this bit starts a conversion sequence. The bit is cleared at the end of the sequence. To stop a sequence prematurely, manually clear this bit.

7.6.1.12 SPECIAL_CFG Register (Offset = Bh) [Reset = 0000h]

Return to the Table 7-13.

Table 7-26 SPECIAL_CFG Register Field Descriptions
Bit Field Type Reset Description
15-3 RESERVED R 0h
2 OTP_LOAD_SW_RST R/W 0h OTP (One Time Programmable Factory Trimmed Registers) LOAD with SW RESET
OTP reloads with the assertion of a software reset (SW_RST).

0h = No reload with SW_RST

1h = Reload with SW_RST

1 ALMV_POL R/W 0h Alarm Voltage Polarity
This register bit is ORed with the POL_SEL/AIN1 pin (if AIN1_ENB bit is low) to control the VOUT during a hardware reset condition or if alarm is active and alarm action is set appropriately. The following Boolean function is implemented for the internal signal ALMV_POL_o that sets the VOUT voltage:

ALMV_POL_o = ALMV_POL OR (POL_SEL/AIN1 AND NOT AIN1_ENB)

0h = Low (0 V)

1h = High (2.5 V)

0 AIN1_ENB R/W 0h AIN1 Pin Enable
This bit determines whether the POL_SEL/AIN1 pin acts as alarm voltage polarity control bit or an input channel to the ADC.

0h = AIN1 pin acts as alarm voltage polarity bit and ADC converts GND

1h = AIN1 pin is an active channel to the ADC

7.6.1.13 MODEM_CFG Register (Offset = Eh) [Reset = 0040h]

Return to the Table 7-13.

Table 7-27 MODEM_CFG Register Field Descriptions
Bit Field Type Reset Description
15 Tx2200Hz R/W 0h Transmit 2200 Hz Only
By not sending data to the FIFO buffer and asserting RTS, the user can transmit multiples of 1200 Hz as long as RTS is asserted. By setting this bit the user can transmit multiples of 2200 Hz. Setting this bit prevents data in the FIFO buffer from being correctly transmitted. If using this bit there is no need to use the FIFO buffer.

0h = Transmit 1200 Hz and 2200 Hz (default)

1h = Transmit only 2200 Hz

14-13 RESERVED R 0h
12 DUPLEX_EXT R/W 0h Duplex External Mode
Allows full duplex mode but expects the connection of MOD_OUT to RX_IN to be made externally.

0h = Internal duplex connection (default)

1h = External duplex connection

11 RX_HORD_EN R/W 0h High Order Filter Enable
Enables a higher order filter on HART_RX.

0h = Disable (default); 1h = Enable

10 RX_EXTFILT_EN R/W 0h External Filter Enable
Enables the use of an external filter for HART_RX. If enabled, then connect the HART signal to RX_INF.

0h = Use internal filter (default); 1h = Use external filter

9 TxRES R/W 0h HART Transmit Resolution

0h = 32 steps per period (default) at 38.4 kHz update rate for 1200 baud

1h = 128 steps per period at 153.6 kHz update rate for 1200 baud

128-step per period waveform consumes more power.

8-4 TxAMP R/W 4h Transmit Amplitude
HART Tx amplitude.

00h = 400 mVPP; 01h = 425 mVPP

02h = 450 mVPP; 03h = 475 mVPP

04h = 500 mVPP (default); 05h = 525 mVPP

06h = 550 mVPP; 07h = 575 mVPP

08h = 600 mVPP; 09h = 625 mVPP

0Ah = 650 mVPP; 0Bh = 675 mVPP

0Ch = 700 mVPP; 0Dh = 725 mVPP

0Eh = 750 mVPP; 0Fh = 775 mVPP

10h through 1Fh = 800 mVPP

3 HART_EN R/W 0h HART Enable
Enable the HART Tx and Rx.

0h = Disable (default); 1h = Enable

2 DUPLEX R/W 0h Duplex Mode
Enable internal connection of Tx to Rx for debug and testing.

0h = Normal operation (default); 1h = Duplex enabled

1 TxHPD R/W 0h HART Tx DAC Output Buffer Hi-Z in Rx Mode or When Disabled

0h = HART Tx DAC output is set to midcode with 50 kΩ output impedance (default)

1h = HART Tx DAC is Hi-Z in Rx mode or when disabled. Users can set the default voltage level with an external circuit.

0 RTS R/W 0h Request To Send Starts transmitting a carrier on MOD_OUT pin.

0h = No action (default)

1h = Request to send. Device starts modulating the MOD_OUT pin if CD = 0.

7.6.1.14 FIFO_CFG Register (Offset = Fh) [Reset = 00F0h]

Return to the Table 7-13.

Table 7-28 FIFO_CFG Register Field Descriptions
Bit Field Type Reset Description
15-10 RESERVED R 0h
9 FIFO_H2U_FLUSH WSC 0h Flush HART-to-µC FIFO (FIFO_H2U)

Clear the pointers for the FIFO_H2U.

8 FIFO_U2H_FLUSH WSC 0h Flush µC-to-HART FIFO (FIFO_U2H)

Clear the pointers for the FIFO_U2H.

7-4 H2U_LEVEL_SET R/W Fh FIFO_H2U FIFO Level Flag Trip Set
Sets the level for FIFO_H2U at which the Level Flag trips. This is a (>) comparison. Because the FIFO size is 5 bits wide, the LSB is not used with this 4-bit setting. Only change this field while MODEM_CFG.HART_EN = 0.
3-0 U2H_LEVEL_SET R/W 0h FIFO_U2H FIFO Level Flag Trip Set
Sets the level for FIFO_U2H at which the Level Flag trips. This is a (<) comparison. Because the FIFO size is 5 bits wide, the LSB is not used with this 4-bit setting. Only change this field while MODEM_CFG.HART_EN = 0.

7.6.1.15 ALARM_ACT Register (Offset = 10h) [Reset = 8020h]

Return to the Table 7-13.

Table 7-29 ALARM_ACT Register Field Descriptions
Bit Field Type Reset Description
15-14 SD_FLT R/W 2h Self-Diagnostic Fault Action

These bits set the device action after a self-diagnostic fault.

0h = No Action

1h = Set DAC to CLEAR state

2h = Switch to alarm voltage determined by ALMV_POL (default)

3h = Place DAC into Hi-Z (power-down)

13-12 TEMP_FLT R/W 0h TEMP Fault Action
These bits set the device action if the ADC temperature is outside the TEMP_THRESHOLD Hi or Lo thresholds.

0h through 3h = Same as SD_FLT field (default 0h)

11-10 AIN1_FLT R/W 0h AIN1 Fault Action
These bits set the device action if the ADC AIN1 channel is outside the AIN1_THRESHOLD Hi or Lo thresholds.

0h through 3h = Same as SD_FLT field (default 0h)

9-8 AIN0_FLT R/W 0h AIN0 Fault Action
These bits set the device action if the ADC AIN0 channel is outside the AIN0_THRESHOLD Hi or Lo thresholds.

0h through 3h = Same as SD_FLT field (default 0h)

7-6 CRC_WDT_FLT R/W 0h CRC and WDT Fault Action
These bits set the device action when a SPI CRC or SPI Watchdog Timeout error occurs.

0h through 3h = Same as SD_FLT field (default 0h)

5-4 VREF_FLT R/W 2h VREF Fault Action
These bits set the device action when a fault is detected on VREF.

0h through 3h = Same as SD_FLT field a

3-2 THERM_ERR_FLT R/W 0h Thermal Error Fault Action
These bits set the device action when a high temperature error occurs (> 130°C).

0h through 3h = Same as SD_FLT field (default 0h)

1-0 THERM_WARN_FLT R/W 0h Thermal Warning Fault Action
These bits set the device action when a high temperature warning occurs (> 85°C).

0h through 3h = Same as SD_FLT field (default 0h)

7.6.1.16 WDT Register (Offset = 11h) [Reset = 0018h]

Return to the Table 7-13.

Table 7-30 WDT Register Field Descriptions
Bit Field Type Reset Description
15-6 RESERVED R 0h
5-3 WDT_UP R/W 3h Watchdog Timer (WDT) Upper Limit
If the WDT is enabled and the timer exceeds the programmed value, a WDT error is asserted. All times are based on 1200-Hz clock (1.2288 MHz / 1024).

0h = 53 ms (64 clocks)

1h = 106 ms (128 clocks)

2h = 427 ms (512 clocks)

3h = 853 ms (1024 clocks, default)

4h = 1.7 s (2048 clocks)

5h = 2.56 s (3072 clocks)

6h = 3.41 s (4096 clocks)

7h = 5.12 s (6144 clocks)

2-1 WDT_LO R/W 0h WDT Lower Limit
If the WDT is enabled and the WDT Lower Limit is enabled, then only a write to this register resets the WDT timer. If the write occurs before the WDT Lower Limit time, or after the WDT Upper Limit time, then a WDT error is asserted. If WDT Lower Limit is disabled, then a write to any register resets the timer. This is true for both SPI and UART Break modes. All times are based on 1200-Hz clock (1.2288 MHz / 1024).

0h = Disabled (default)

1h = 53 ms (64 clocks)

2h = 106 ms (128 clocks)

3h = 427 ms (512 clocks)

0 WDT_EN R/W 0h WDT Enable

0h = Disabled (default); 1h = Enabled

7.6.1.17 AIN0_THRESHOLD Register (Offset = 12h) [Reset = FF00h]

Return to the Table 7-13.

Table 7-31 AIN0_THRESHOLD Register Field Descriptions
Bit Field Type Reset Description
15-8 Hi R/W FFh
High Threshold for Channel AIN0 {[11:4],4b1111}
This value is compared (>) against AIN0 data bits[11:0].
7-0 Lo R/W 0h
Low Threshold for Channel AIN0 {[11:4],4b0000}
This value is compared (<) against AIN0 data bits[11:0].

7.6.1.18 AIN1_THRESHOLD Register (Offset = 13h) [Reset = FF00h]

Return to the Table 7-13.

Table 7-32 AIN1_THRESHOLD Register Field Descriptions
Bit Field Type Reset Description
15-8 Hi R/W FFh
High Threshold for Channel AIN1 {[11:4],4b1111}
This value is compared (>) against AIN1 data bits[11:0].
7-0 Lo R/W 0h
Low Threshold for Channel AIN1 {[11:4],4b0000}
This value is compared (<) against AIN1 data bits[11:0].

7.6.1.19 TEMP_THRESHOLD Register (Offset = 14h) [Reset = FF00h]

Return to the Table 7-13.

Table 7-33 TEMP_THRESHOLD Register Field Descriptions
Bit Field Type Reset Description
15-8 Hi R/W FFh
High Threshold for Channel TEMP {[11:4],4b1111}
This value is compared (>) against TEMP data bits[11:0].
7-0 Lo R/W 0h
Low Threshold for Channel TEMP {[11:4],4b0000}
This value is compared (<) against TEMP data bits[11:0].

7.6.1.20 FIFO_U2H_WR Register (Offset = 15h) [Reset = 0000h]

Return to the Table 7-13.

This register controls the HART to microcontroller FIFO buffer.

Table 7-34 FIFO_U2H_WR Register Field Descriptions
Bit Field Type Reset Description
15-9 RESERVED R 0h
8 PARITY WO 0h Parity
Odd parity bit to be transmitted with data. This field can only be written by SPI and affects the FIFO when CONFIG.UART_DIS = 1. Otherwise writes to this register are ignored.
7-0 DATA WO 0h Data Byte
This field can only be written by SPI and affects the FIFO when CONFIG.UART_DIS = 1. Otherwise writes to this register are ignored.

7.6.1.21 UBM Register (Offset = 16h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-35 UBM Register Field Descriptions
Bit Field Type Reset Description
15-1 RESERVED R 0h
0 REG_MODE R/W 0h Register Mode
Configure the rest of the Register Map to be accessed by UART break mode (UBM) or SPI. This register can only be written by the UART Break communication.

0h = SPI Mode (default)

1h = UART Break Mode

7.6.1.22 ALARM_STATUS_MASK Register (Offset = 1Dh) [Reset = EFDFh]

Return to the Table 7-13.

Table 7-36 ALARM_STATUS_MASK Register Field Descriptions
Bit Field Type Reset Description
15-14 RESERVED R 3h
13 SD_FLT R/W 1h SD Fault Mask

0h = Fault asserts IRQ

1h = The mask prevents IRQ or Alarm being triggered (default).
The status is always set if the condition exists.

12 OSC_FAIL R/W 0h OSC_FAIL Fault Mask

Same as SD Fault Mask (default 0h).

11-9 RESERVED R 7h
8 OTP_CRC_ERR R/W 1h OTP CRC Error Mask

Same as SD Fault Mask (default 1h).

7 CRC_FLT R/W 1h SPI CRC Fault Mask

Same as SD Fault Mask (default 1h).

6 WD_FLT R/W 1h Watchdog Fault Mask

Same as SD Fault Mask (default 1h).

5 VREF_FLT R/W 0h VREF Fault Mask

Same as SD Fault Mask (default 0h).

4 ADC_AIN1_FLT R/W 1h ADC AIN1 Fault Mask

Same as SD Fault Mask (default 1h).

3 ADC_AIN0_FLT R/W 1h ADC AIN0 Fault Mask

Same as SD Fault Mask (default 1h).

2 ADC_TEMP_FLT R/W 1h ADC TEMP Fault Mask

Same as SD Fault Mask (default 1h).

1 THERM_ERR_FLT R/W 1h Temperature > 130°C Error Mask

Same as SD Fault Mask (default 1h).

0 THERM_WARN_FLT R/W 1h Temperature > 85°C Warning Mask

Same as SD Fault Mask (default 1h).

7.6.1.23 GEN_STATUS_MASK Register (Offset = 1Eh) [Reset = FFFFh]

Return to the Table 7-13.

Table 7-37 GEN_STATUS_MASK Register Field Descriptions
Bit Field Type Reset Description
15-11 RESERVED R 1Fh
10 MBIST_DONE R/W 1h MBIST Done Mask

0h = Fault asserts IRQ

1h = The mask prevents IRQ or Alarm being triggered (default).
The status is always set if the condition exists.

9 MBIST_FAIL R/W 1h MBIST Failed Fault Mask

Same as MBIST Done Mask (default 1h).

8 RESERVED R 1h
7 SR_BUSYn R/W 1h Slew Rate Not Busy Mask

Same as MBIST Done Mask (default 1h).

6 ADC_EOC R/W 1h ADC End Of Conversion Mask

Same as MBIST Done Mask (default 1h).

5-4 RESERVED R 3h
3 BREAK_FRAME_ERR R/W 1h Break Frame Error Fault Mask

Same as MBIST Done Mask (default 1h).

2 BREAK_PARITY_ERR R/W 1h Break Parity Error Fault Mask

Same as MBIST Done Mask (default 1h).

1 UART_FRAME_ERR R/W 1h UART Frame Error Fault Mask

Same as MBIST Done Mask (default 1h).

0 UART_PARITY_ERR R/W 1h UART Parity Error Fault Mask

Same as MBIST Done Mask (default 1h).

7.6.1.24 MODEM_STATUS_MASK Register (Offset = 1Fh) [Reset = FFFFh]

Return to the Table 7-13.

Table 7-38 MODEM_STATUS_MASK Register Field Descriptions
Bit Field Type Reset Description
15-13 RESERVED R 7h
12 GAP_ERR R/W 1h HART Gap Error Fault Mask

0h = Fault asserts IRQ

1h = The mask prevents IRQ or Alarm being triggered (default).
The status is always set if the condition exists.

11 FRAME_ERR R/W 1h HART Frame Error Fault Mask

Same as HART Gap Error Fault Mask (default 1h).

10 PARITY_ERR R/W 1h HART Parity (ODD) Error Fault Mask

Same as HART Gap Error Fault Mask (default 1h).

9 FIFO_H2U_LEVEL_FLAG R/W 1h FIFO_H2U Level Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

8 FIFO_H2U_FULL_FLAG R/W 1h FIFO_H2U Full Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

7 FIFO_H2U_EMPTY_FLAG R/W 1h FIFO_H2U Empty Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

6 FIFO_U2H_LEVEL_FLAG R/W 1h FIFO_U2H Level Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

5 FIFO_U2H_FULL_FLAG R/W 1h FIFO_U2H Full Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

4 FIFO_U2H_EMPTY_FLAG R/W 1h FIFO_U2H Empty Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

3 CD_DEASSERT R/W 1h CD Deasserted Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

2 CD_ASSERT R/W 1h CD Asserted Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

1 CTS_DEASSERT R/W 1h CTS Deasserted Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

0 CTS_ASSERT R/W 1h CTS Asserted Flag Mask

Same as HART Gap Error Fault Mask (default 1h).

7.6.1.25 ALARM_STATUS Register (Offset = 20h) [Reset = 0200h]

Return to the Table 7-13.

Table 7-39 ALARM_STATUS Register Field Descriptions
Bit Field Type Reset Description
15 GEN_IRQ R 0h General IRQ OR of all the unmasked bits in the GEN_STATUS register.

0h = All of the unmasked bits of the GEN_STATUS register are low

1h = At least one of the unmasked bits in the GEN_STATUS register is high

14 MODEM_IRQ R 0h Modem IRQ OR of all the unmasked bits in the MODEM_STATUS register.

0h = All of the unmasked bits of the MODEM_STATUS register are low

1h = At least one of the unmasked bits in the MODEM_STATUS register is high

13 SD_FLT R 0h Self Diagnostic (SD) Fault

0h = All self diagnostic channels are within threshold limits

1h = At least one of the self diagnostic channels has failed

12 OSC_FAIL R 0h Oscillator Fault Oscillator failed to start. This bit holds ALARM low and does not feed IRQ.

0h = Oscillator started; 1h = Oscillator has failed to start

11-10 CRC_CNT R 0h CRC Fault Counter
If counter limit ≤ 4 then bits[1:0] of the counter are shown here.
If the counter limit = 8 then bits[2:1] of the counter are shown.
9 OTP_LOADEDn R 1h OTP NOT Loaded Clears when OTP has loaded at least once.
Keeps ALARM asserted until OTP finishes loading. Does not feed IRQ.

0h = OTP has loaded at least once; 1h = OTP has not finished loading

8 OTP_CRC_ERR R 0h OTP CRC Error Maskable fault. An error occurred with the OTP CRC calculation.
Sticky, cleared by reading register, unless condition still persist.

0h = No OTP CRC fault; 1h = OTP CRC fault

7 CRC_FLT R 0h CRC Fault Maskable fault. Invalid CRC value transmitted during SPI frame.
Sticky, cleared by reading register, unless condition still persist.

0h = No CRC fault; 1h = CRC fault

6 WD_FLT R 0h Watchdog Timer Fault
Maskable fault. Sticky, cleared by reading register, unless condition still persist.

0h = No watchdog fault; 1h = Watchdog fault

5 VREF_FLT R 0h Invalid Reference Voltage Maskable fault. OR with FORCE_FAIL.VREF_FLT bit.
Active signal, set as long as condition is true. Direct input from analog circuit.

0h = Valid VREF voltage; 1h = Invalid VREF voltage

4 ADC_AIN1_FLT R 0h ADC AIN1 Fault. Maskable fault.

0h = AIN1 ADC measurement within threshold limits

1h = AIN1 ADC measurement outside threshold limits

3 ADC_AIN0_FLT R 0h ADC AIN0 Fault. Maskable fault.

0h = AIN0 ADC measurement within threshold limits

1h = AIN0 ADC measurement outside threshold limits

2 ADC_TEMP_FLT R 0h ADC Temp Fault. Maskable fault.

0h = TEMP ADC measurement within threshold limits

1h = TEMP ADC measurement outside threshold limits

1 THERM_ERR_FLT R 0h Temperature > 130°C error. Maskable fault.
OR with FORCE_FAIL.THERM_ERR_FLT bit.
Active signal, set as long as condition is true. Direct input from analog circuit.

0h = Temperature ≤ 130°C; 1h = Temperature > 130°C

0 THERM_WARN_FLT R 0h Temperature > 85°C warning. Maskable fault.
OR with FORCE_FAIL.THERM_WARN_FLT bit.
Active signal, set as long as condition is true. Direct input from analog circuit.

0h = Temperature ≤ 85°C; 1h = Temperature > 85°C

7.6.1.26 GEN_STATUS Register (Offset = 21h) [Reset = 1180h]

Return to the Table 7-13.

Table 7-40 GEN_STATUS Register Field Descriptions
Bit Field Type Reset Description
15 ALARM_IRQ R 0h Alarm IRQ OR of all the unmasked bits in the ALARM_STATUS register.

0h = All of the unmasked bits of the ALARM_STATUS register are low

1h = At least one of the unmasked bits in the ALARM_STATUS register is high

14

MODEM_IRQ

R 0h Modem IRQ OR of all the unmasked bits in the MODEM_STATUS register.

0h = All of the unmasked bits of the MODEM_STATUS register are low

1h = At least one of the unmasked bits in the MODEM_STATUS register is high

13 RESERVED R 0h
12 OTP_BUSY R 1h OTP Busy Status = 1h at power up while the OTP is being loaded into the trim latches.

0h = OTP has completed loading into the device

1h = OTP is being loaded into the device

11 RESERVED R 0h
10 MBIST_DONE R 0h MBIST Completed. Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = MBIST has not completed; 1h = MBIST has completed

9 MBIST_FAIL R 0h MBIST Failed. Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = MBIST has passed; 1h = MBIST has failed

8 RESET R 1h Device Reset Occurred. Status only. Does not feed IRQ.
Sticky, cleared by reading register, unless condition still persist.

0h = Device has not reset since last read of register

1h = Device has reset since last read of register

7 SR_BUSYn R 1h Slew Rate Not Busy. Maskable fault.
0h = DAC is slewing to the target code
1h = DAC_OUT has reached the DAC_DATA.
If slew rate is disabled, then this signal produces a rising edge within 3 internal clock cycles. If slew rate is enabled, this signal creates an IRQ event when the DAC_OUT has reached the DAC_DATA. At this time, slew rate can be safely disabled. If slew rate is disabled prior to DAC_OUT = DAC_DATA then a jump of DAC_OUT occurs. This can cause an unwanted fast transition on VOUT.
6 ADC_EOC R 0h ADC End of Conversion (EOC). Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = No EOC since last read of register; 1h = ADC end of conversion

5 ADC_BUSY R 0h ADC Busy. Status only. Does not feed IRQ. Active signal, set as long as condition is true.

0h = No ADC activity; 1h = ADC is actively converting

4 PVDD_HI R 0h PVDD High. Status only. Does not feed IRQ. Set as long as condition is true.

0h = PVDD < 2.7 V; 1h = PVDD ≥ 2.7V

3 BREAK_
FRAME_ERR
R 0h Incorrect Stop Bit During Break Character. Maskable fault. Applies to UARTIN.
Sticky, cleared by reading register, unless condition still persist.

0h = No break frame error; 1h = Break frame error

2 BREAK_
PARITY_ERR
R 0h Incorrect parity (ODD) bit during break character. Maskable fault. Applies to UARTIN.
Sticky, cleared by reading register, unless condition still persist.

0h = No break parity error; 1h = Break parity error

1 UART_
FRAME_ERR
R 0h Incorrect stop bit during UART character. Maskable fault. Applies to UARTIN.
Sticky, cleared by reading register, unless condition still persist.

0h = No UART frame error; 1h = UART frame error

0 UART_
PARITY_ERR
R 0h Incorrect parity (ODD) bit during UART character. Maskable fault. Applies to UARTIN.
Sticky, cleared by reading register, unless condition still persist.

0h = No UART parity error; 1h = UART parity error

7.6.1.27 MODEM_STATUS Register (Offset = 22h) [Reset = 009Ah]

Return to the Table 7-13.

Table 7-41 MODEM_STATUS Register Field Descriptions
Bit Field Type Reset Description
15 ALARM_IRQ R 0h Alarm IRQ OR of all the unmasked bits in the ALARM_STATUS register.

0h = All of the unmasked bits of the ALARM_STATUS register are low

1h = At least one of the unmasked bits in the ALARM_STATUS register is high

14 GEN_IRQ R 0h General IRQ OR of all the unmasked bits in the GEN_STATUS register.

0h = All of the unmasked bits of the GEN_STATUS register are low

1h = At least one of the unmasked bits in the GEN_STATUS register is high

13 RESERVED R 0h
12 GAP_ERR R 0h HART Gap Error. Maskable fault. Applies to RX_IN/RX_INF.
Too much time (11 bit times) between HART characters.
Sticky, cleared by reading register, unless condition still persist. Fatal Fault.

0h = No HART gap error; 1h = HART gap error

11 FRAME_ERR R 0h Incorrect Stop Bit in HART Character. Maskable fault. Applies to RX_IN/RX_INF.
Sticky, cleared by reading register, unless condition still persist. Fatal Fault.

0h = No HART frame error; 1h = HART frame error

10 PARITY_ERR R 0h Incorrect Parity (ODD) Bit in HART Character. Maskable fault. Applies to RX_IN/RX_INF.
Sticky, cleared by reading register, unless condition still persist.

0h = No HART parity error; 1h = HART parity error

9 FIFO_H2U_
LEVEL_FLAG
R 0h FIFO HART-to-µC Level Flag. Maskable fault.
If the level of the FIFO_H2U is full, then the level flag is not asserted, but the full flag is, so no information is lost.

0h = FIFO_H2U level ≤ {FIFO_CFG.H2U_LEVEL_SET[3:0], 1b1}

1h = FIFO_H2U level > {FIFO_CFG.H2U_LEVEL_SET[3:0], 1b1}

8 FIFO_H2U_
FULL_FLAG
R 0h FIFO HART-to-µC Full Flag. Maskable fault.

0h = FIFO_H2U is not full; 1h = FIFO_H2U is full

7 FIFO_H2U_
EMPTY_FLAG
R 1h FIFO HART-to-µC Empty Flag. Maskable fault.

0h = FIFO_H2U is not empty; 1h = FIFO_H2U is empty

6 FIFO_U2H_
LEVEL_FLAG
R 0h FIFO µC-to-HART Level Flag. Maskable fault.
FIFO_U2H < {FIFO_CFG.U2H_LEVEL_SET[3:0], 1b0}. When the FIFO_U2H is empty, this flag is set unless FIFO_CFG.U2H_LEVEL_SET = 0. This flag and the empty flag can be set at the same time.

0h = FIFO_U2H level ≥ {FIFO_CFG.U2H_LEVEL_SET[3:0], 1b0}

1h = FIFO_U2H level < {FIFO_CFG.U2H_LEVEL_SET[3:0], 1b0}

5 FIFO_U2H_
FULL_FLAG
R 0h FIFO µC-to-HART Full Flag. Maskable fault.

0h = FIFO_U2H is not full; 1h = FIFO_U2H is full

4 FIFO_U2H_
EMPTY_FLAG
R 1h FIFO µC-to-HART Empty Flag. Maskable fault.

0h = FIFO_U2H is not empty; 1h = FIFO_U2H is empty

3 CD_DEASSERT R 1h Carrier Detect Deasserted. Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = Carrier detect is asserted; 1h = Carrier detect is deasserted

2 CD_ASSERT R 0h Carrier Detect Asserted. Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = Carrier detect is deasserted; 1h = Carrier detect is asserted

1 CTS_DEASSERT R 1h Clear To Send Deasserted. Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = Clear to send is asserted; 1h = Clear to send is deasserted

0 CTS_ASSERT R 0h Clear To Send Asserted. Maskable fault.
Sticky, cleared by reading register, unless condition still persist.

0h = Clear to send is deasserted; 1h = Clear to send is asserted

7.6.1.28 ADC_FLAGS Register (Offset = 23h) [Reset = 0000h]

Return to the Table 7-13.

The limits for Self Diagnostic (SD) Alarm ADC Thresholds are shown in Table 7-7.
Table 7-42 ADC_FLAGS Register Field Descriptions
Bit Field Type Reset Description
15-9 RESERVED R 0h
8 SD4_FAIL R 0h SD4 (VOUT) Limit Fail
7 SD3_FAIL R 0h SD3 (ZTAT) Limit Fail
6 SD2_FAIL R 0h SD2 (VDD) Limit Fail
5 SD1_FAIL R 0h SD1 (PVDD) Limit Fail
4 SD0_FAIL R 0h SD0 (VREF) Limit Fail
3 TEMP_FAIL R 0h TEMP Limit Fail
2 AIN1_FAIL R 0h AIN1 Limit Fail
1 AIN0_FAIL R 0h AIN0 Limit Fail
0 RESERVED R 0h

7.6.1.29 ADC_AIN0 Register (Offset = 24h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-43 ADC_AIN0 Register Field Descriptions
Bit Field Type Reset Description
15-12 RESERVED R 0h
11-0 DATA R 0h Converted Value of Voltage on Pin AIN0

7.6.1.30 ADC_AIN1 Register (Offset = 25h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-44 ADC_AIN1 Register Field Descriptions
Bit Field Type Reset Description
15-12 RESERVED R 0h
11-0 DATA R 0h Converted Value of Voltage on Pin AIN1

7.6.1.31 ADC_TEMP Register (Offset = 26h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-45 ADC_TEMP Register Field Descriptions
Bit Field Type Reset Description
15-12 RESERVED R 0h
11-0 DATA R 0h Converted Value of Temperature

7.6.1.32 ADC_SD_MUX Register (Offset = 27h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-46 ADC_SD_MUX Register Field Descriptions
Bit Field Type Reset Description
15-12 RESERVED R 0h
11-0 DATA R 0h Converted Value of Voltage on Self-Diagnostic (SD) MUX Input

7.6.1.33 ADC_OFFSET Register (Offset = 28h) [Reset = 0000h]

Return to the Table 7-13.

Table 7-47 ADC_OFFSET Register Field Descriptions
Bit Field Type Reset Description
15-12 RESERVED R 0h
11-0 DATA R 0h ADC Comparator Offset
This value reports the offset measured in the device, and can be used to adjust each conversion value. If ADC_BYP.OFST_BYP_EN is set, then the value in ADC_BYP.DATA is used as the offset. This value is not affected by ADC_BYP.

7.6.1.34 FIFO_H2U_RD Register (Offset = 2Ah) [Reset = 0200h]

Return to the Table 7-13.

Table 7-48 FIFO_H2U_RD Register Field Descriptions
Bit Field Type Reset Description
15-12 LEVEL R 0h Level
Current Level of FIFO_H2U, bits [4:1] represented as Level[3:0]. Pre-dequeue.
11 LEVEL_FLAG R 0h HART-to-µC FIFO Level Flag
Set when FIFO_H2U Level > {Level,1b1}. Pre-dequeue.

0h = FIFO_H2U level ≤ {Level, 1b1}

1h = FIFO_H2U level > {Level, 1b1}

10 FULL_FLAG R 0h HART-to-µC FIFO Full Flag. Pre-dequeue.

0h = FIFO_H2U is not full, pre-dequeue

1h = FIFO_H2U is full, pre-dequeue

9 EMPTY_FLAG R 1h HART-to-µC FIFO Empty Flag. Pre-dequeue.

0h = FIFO_H2U is not empty

1h = FIFO_H2U is empty

8 PARITY R 0h Parity Bit (ODD)
Parity bit received with data on HART. This field can only be read by SPI when CONFIG.UART_DIS = 1. Otherwise reads from this register are ignored and do not dequeue FIFO. The default value is unknown until data are written to the FIFO.
7-0 DATA R 0h Data
8-bit data received on HART. This field can only be read by SPI when CONFIG.UART_DIS = 1. Otherwise reads from this register are ignored and do not dequeue FIFO. The default value is unknown until data are written to the FIFO.

7.6.1.35 FIFO_STATUS Register (Offset = 2Bh) [Reset = 0202h]

Return to the Table 7-13.

The FIFO_STATUS register is provided to allow the user to view the state of both FIFOs without enqueuing or dequeuing data in the FIFO. This also allows the flags to be viewed without disturbing other status bits in the MODEM_STATUS register. This register is provided to enable users to check the FIFO status register without disturbing other functions within the device.

Table 7-49 FIFO_STATUS Register Field Descriptions
Bit Field Type Reset Description
15-12 H2U_LEVEL R 0h HART-to-µC FIFO Level
Current level of FIFO_H2U, right shifted 1 bit (>>1) so only even counts are represented.
11 H2U_LEVEL_FLAG R 0h HART-to-µC FIFO Level Flag
Set when FIFO Level > {Level,1b1}.

0h = FIFO_H2U level ≤ {Level, 1b1}

1h = FIFO_H2U level > {Level, 1b1}

10 H2U_FULL_FLAG R 0h HART-to-µC FIFO Full Flag
Set when FIFO is full.

0h = FIFO_H2U is not full

1h = FIFO_H2U is full

9 H2U_EMPTY_FLAG R 1h HART-to-µC Empty Flag
Set when FIFO is empty.

0h = FIFO_H2U is not empty

1h = FIFO_H2U is empty

8 RESERVED R 0h
7-4 U2H_LEVEL R 0h µC-to-HART FIFO Level
Current level of FIFO_U2H, right shifted 1 bit (>>1) so only even counts are represented
3 U2H_LEVEL_FLAG R 0h µC-to-HART FIFO Level Flag
Set when FIFO_U2H Level < {Level,1b0}.

0h = FIFO_U2H level ≥ {Level, 1b0}

1h = FIFO_U2H level < {Level, 1b0}

2 U2H_FULL_FLAG R 0h µC-to-HART Full Flag
Set when FIFO_U2H is full.

0h = FIFO_U2H is not full

1h = FIFO_U2H is full

1 U2H_EMPTY_FLAG R 1h µC-to-HART Empty Flag
Set when FIFO_U2H is empty.

0h = FIFO_U2H is not empty

1h = FIFO_U2H is empty

0 RESERVED R 0h

7.6.1.36 DAC_OUT Register (Offset = 2Ch) [Reset = 0000h]

Return to the Table 7-13.

Table 7-50 DAC_OUT Register Field Descriptions
Bit Field Type Reset Description
15-0 DATA R 0h
DAC Code Applied to the Analog Circuit

7.6.1.37 ADC_OUT Register (Offset = 2Dh) [Reset = 0000h]

Return to the Table 7-13.

Table 7-51 ADC_OUT Register Field Descriptions
Bit Field Type Reset Description
15-12 RESERVED R 0h
11-0 DATA R 0h ADC Data for Each Conversion
Does not include ADC_OFFSET.DATA adjustment. Is not affected by ADC_BYP.DATA.

7.6.1.38 ADC_BYP Register (Offset = 2Eh) [Reset = 0000h]

Return to the Table 7-13.

ADC_BYP is shown in Table 7-52.

Table 7-52 ADC_BYP Register Field Descriptions
Bit Field Type Reset Description
15 DATA_BYP_EN R/W 0h Data Bypass Enable
Applies ADC_BYP.DATA to the ADC channel being converted. ADC_OFFSET is ignored. Do not set OFST_BYP_EN and DATA_BYP_EN at the same time. If OFST_BYP_EN is also set, DATA_BYP_EN takes priority over OFST_BYP_EN. After a channel is converted, the ADC_BYP.DATA value appears in the readback register for the converted channel and is used to calculate faults.

0h = Data bypass disabled (default)

1h = Data bypass enabled

14 OFST_BYP_EN R/W 0h Offset Bypass Enable
Overrides the offset register with the ADC_BYP.DATA value. When using this bit, the ADC_BYP.DATA field is processed as 2's complement. Do not set OFST_BYP_EN and DATA_BYP_EN at the same time.

0h = Offset bypass disabled (default)

1h = Offset bypass enabled

13 DIS_GND_SAMP R/W 0h Disable GND Sampling
This bit disables the sampling of GND during SAR activity. The sampling of GND is used to fully discharge the sampling CAP to reduce channel crosstalk.

0h = GND sampling enabled (default)

1h = GND sampling disabled

12 RESERVED R 0h
11-0 DATA R/W 0h Bypass Data

7.6.1.39 FORCE_FAIL Register (Offset = 2Fh) [Reset = 0000h]

Return to the Table 7-13.

Force failures for fault detection.

Table 7-53 FORCE_FAIL Register Field Descriptions
Bit Field Type Reset Description
15 CRC_FLT R/W 0h Force CRC Failure on SDO by Inverting the CRC Byte

0h = No force failure of CRC (default)

1h = Force failure of CRC

14 VREF_FLT R/W 0h Force Reference Voltage Failure. Analog signal.

0h = No force failure of VREF (default)

1h = Force failure of VREF

13 THERM_ERR_FLT R/W 0h Force Temperature > 130°C Thermal Error. Analog signal.

0h = No force temperature > 130°C error (default)

1h = Force temperature > 130°C error

12 THERM_WARN_FLT R/W 0h Force Temperature > 85°C thermal Warning. Analog signal.

0h = No force temperature > 85°C warning (default)

1h = Force temperature > 85°C warning

11-10 RESERVED R/W 0h
9 SD4_HI_FLT R/W 0h SD4 (VOUT) High Limit Failure. ADC measurement.

0h = No force failure of SD4 (VOUT) (default)

1h = Force failure of SD4 (VOUT)

8 SD4_LO_FLT R/W 0h SD4 (VOUT) Low limit failure. ADC measurement.

0h = No force failure of SD4 (VOUT) (default)

1h = Force failure of SD4 (VOUT)

7 SD3_HI_FLT R/W 0h SD3 (ZTAT) High Limit Failure. ADC measurement.

0h = No force failure of SD3 (ZTAT) (default)

1h = Force failure of SD3 (ZTAT)

6 SD3_LO_FLT R/W 0h SD3 (ZTAT) Low Limit Failure. ADC measurement.

0h = No force failure of SD3 (ZTAT) (default)

1h = Force failure of SD3 (ZTAT)

5 SD2_HI_FLT R/W 0h SD2 (VDD) High Limit Failure. ADC measurement.

0h = No force failure of SD2 (VDD) (default)

1h = Force failure of SD2 (VDD)

4 SD2_LO_FLT R/W 0h SD2 (VDD) Low Limit Failure. ADC measurement.

0h = No force failure of SD2 (VDD) (default)

1h = Force failure of SD2 (VDD)

3 SD1_HI_FLT R/W 0h SD1 (PVDD) High Limit Failure. ADC measurement.

0h = No force failure of SD1 (PVDD) (default)

1h = Force failure of SD1 (PVDD)

2 SD1_LO_FLT R/W 0h SD1 (PVDD) Low Limit Failure. ADC measurement.

0h = No force failure of SD1 (PVDD) (default)

1h = Force failure of SD1 (PVDD)

1 SD0_HI_FLT R/W 0h SD0 (VREF) High Limit Failure. ADC measurement.

0h = No force failure of SD0 (VREF) (default)

1h = Force failure of SD0 (VREF)

0 SD0_LO_FLT R/W 0h SD0 (VREF) Low Limit Failure. ADC measurement.

0h = No force failure of SD0 (VREF) (default)

1h = Force failure of SD0 (VREF)