SBASAW5 December   2025 ADS112C14 , ADS122C14

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 I2C Timing Requirements
    7. 5.7 I2C Switching Characteristics
    8. 5.8 Timing Diagrams
    9. 5.9 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Noise Performance
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Analog Inputs and Multiplexer
      2. 7.3.2  Programmable Gain Amplifier (PGA)
      3. 7.3.3  Voltage Reference
        1. 7.3.3.1 Internal Reference
        2. 7.3.3.2 External Reference
        3. 7.3.3.3 Reference Buffers
      4. 7.3.4  Clock Source
      5. 7.3.5  Delta-Sigma Modulator
      6. 7.3.6  Digital Filter
        1. 7.3.6.1 Sinc4 and Sinc4 + Sinc1 Filter
        2. 7.3.6.2 FIR Filter
        3. 7.3.6.3 Digital Filter Latency
        4. 7.3.6.4 Global-Chop Mode
      7. 7.3.7  Excitation Current Sources (IDACs)
      8. 7.3.8  Burn-Out Current Sources (BOCS)
      9. 7.3.9  General Purpose IOs (GPIOs)
        1. 7.3.9.1 FAULT Output
        2. 7.3.9.2 DRDY Output
      10. 7.3.10 System Monitors
        1. 7.3.10.1 Internal Short (Offset Calibration)
        2. 7.3.10.2 Internal Temperature Sensor
        3. 7.3.10.3 External Reference Voltage Readback
        4. 7.3.10.4 Power-Supply Readback
      11. 7.3.11 Monitors and Status Flags
        1. 7.3.11.1 Reset (RESETn flag)
        2. 7.3.11.2 AVDD Undervoltage Monitor (AVDD_UVn flag)
        3. 7.3.11.3 Reference Undervoltage Monitor (REV_UVn flag)
        4. 7.3.11.4 Register Map CRC Fault (REG_MAP_CRC_FAULTn flag)
        5. 7.3.11.5 Internal Memory Fault (MEM_FAULTn flag)
        6. 7.3.11.6 Register Write Fault (REG_WRITE_FAULTn flag)
        7. 7.3.11.7 DRDY Indicator (DRDY bit)
        8. 7.3.11.8 Conversion Counter (CONV_COUNT[3:0])
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power-up and Reset
        1. 7.4.1.1 Power-On Reset (POR)
        2. 7.4.1.2 Reset by Register Write
        3. 7.4.1.3 I2C General Call Reset
      2. 7.4.2 Operating Modes
        1. 7.4.2.1 Idle and Standby Mode
        2. 7.4.2.2 Power-Down Mode
        3. 7.4.2.3 Power-Scalable Conversion Modes
          1. 7.4.2.3.1 Continuous-Conversion Mode
          2. 7.4.2.3.2 Single-shot Conversion Mode
    5. 7.5 Programming
      1. 7.5.1  I2C Interface
      2. 7.5.2  I2C Address
      3. 7.5.3  Serial Clock (SCL) and Serial Data (SDA)
      4. 7.5.4  I2C Bus Speed
      5. 7.5.5  I2C Data Transfer Protocol
      6. 7.5.6  I2C General Call (Software Reset)
      7. 7.5.7  I3C Compatibility
      8. 7.5.8  Commands
        1. 7.5.8.1 RDATA (0000 0000b)
        2. 7.5.8.2 RREG (0100 rrrrb)
        3. 7.5.8.3 WREG (1000 rrrrb)
      9. 7.5.9  STATUS Header
      10. 7.5.10 I2C CRC
      11. 7.5.11 Register Map CRC
      12. 7.5.12 Data Ready (DRDY) Pin
      13. 7.5.13 Monitoring for New Conversion Data
        1. 7.5.13.1 DRDY Pin Monitoring
        2. 7.5.13.2 Reading DRDY Bit and Conversion Counter
        3. 7.5.13.3 Clock Counting
      14. 7.5.14 Conversion Data Format
  9. 8 Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Serial Interface Connections
      2. 9.1.2 Connecting Multiple Devices on the Same I2C Bus
      3. 9.1.3 Unused Inputs and Outputs
      4. 9.1.4 Device Initialization
    2. 9.2 Typical Applications
      1. 9.2.1 Software-Configurable RTD Measurement Input
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Performance Plots
        4. 9.2.1.4 Design Variant – 3-Wire RTD Measurement With Automatic Lead-Wire Compensation Using Two IDACs
      2. 9.2.2 Thermocouple Measurement With Cold-Junction Compensation Using a 2-wire RTD
      3. 9.2.3 Resistive Bridge Sensor Measurement With Temperature Compensation
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Power Supplies
      2. 9.3.2 Power-Supply Sequencing
      3. 9.3.3 Power-Supply Decoupling
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

7.3.4 Clock Source

The ADS1x2C14 require a main clock for operation. The main clock is provided in one of two ways:

  • The internal low-drift 4.096MHz oscillator or
  • An external clock on the CLK input pin

Use the CLK_SEL bit to select the clock source. At device power-up or after device reset, the internal oscillator is selected as the clock source by default.

The external CLK input is combined with the AIN7/GPIO3 pin. To change from the internal oscillator to the external clock, first set GPIO3_CFG = 01b to configure the GPIO3 pin as external clock input, then set CLK_SEL = 1b.

The modulator clock for the delta-sigma ADC is derived from the main clock. A clock divider divides the main clock frequency (fCLK) by a division factor based on the selected speed mode to create the modulator frequency (fMOD = fCLK / DIV). Table 7-2 shows the respective clock divider settings per speed mode together with the nominal modulator frequencies.

Table 7-2 Clock Divider Settings
SPEED MODE CLOCK DIVIDER
(DIV)		 MODULATOR FREQUENCY
(fMOD)(1)
0 128 32kHz
1 16 256kHz
2 8 512kHz
3 4 1.024MHz
(1) Using a nominal clock frequency of fCLK = 4.096MHz.