SBAS852A August   2017  – February 2020 ADS114S06B , ADS114S08B

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Functional Block Diagram
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 Typical Characteristics
  8. Parameter Measurement Information
    1. 8.1 Noise Performance
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Multiplexer
      2. 9.3.2  Low-Noise Programmable Gain Amplifier
        1. 9.3.2.1 PGA Input-Voltage Requirements
        2. 9.3.2.2 Bypassing the PGA
      3. 9.3.3  Voltage Reference
        1. 9.3.3.1 Internal Reference
        2. 9.3.3.2 External Reference
        3. 9.3.3.3 Reference Buffers
      4. 9.3.4  Clock Source
      5. 9.3.5  Delta-Sigma Modulator
      6. 9.3.6  Digital Filter
        1. 9.3.6.1 Digital Filter Frequency Response
        2. 9.3.6.2 Data Conversion Time
        3. 9.3.6.3 Note on Conversion Time
        4. 9.3.6.4 50-Hz and 60-Hz Line Cycle Rejection
      7. 9.3.7  Excitation Current Sources (IDACs)
      8. 9.3.8  Bias Voltage Generation
      9. 9.3.9  System Monitor
        1. 9.3.9.1 Internal Temperature Sensor
        2. 9.3.9.2 Power Supply Monitors
        3. 9.3.9.3 Burn-Out Current Sources
      10. 9.3.10 Status Register
        1. 9.3.10.1 POR Flag
        2. 9.3.10.2 RDY Flag
        3. 9.3.10.3 External Reference Monitor
      11. 9.3.11 General-Purpose Inputs and Outputs (GPIOs)
      12. 9.3.12 Calibration
        1. 9.3.12.1 Offset Calibration
        2. 9.3.12.2 Gain Calibration
    4. 9.4 Device Functional Modes
      1. 9.4.1 Reset
        1. 9.4.1.1 Power-On Reset
        2. 9.4.1.2 RESET Pin
        3. 9.4.1.3 Reset by Command
      2. 9.4.2 Power-Down Mode
      3. 9.4.3 Standby Mode
      4. 9.4.4 Conversion Modes
        1. 9.4.4.1 Continuous Conversion Mode
        2. 9.4.4.2 Single-Shot Conversion Mode
    5. 9.5 Programming
      1. 9.5.1 Serial Interface
        1. 9.5.1.1 Chip Select (CS)
        2. 9.5.1.2 Serial Clock (SCLK)
        3. 9.5.1.3 Serial Data Input (DIN)
        4. 9.5.1.4 Serial Data Output and Data Ready (DOUT/DRDY)
        5. 9.5.1.5 Data Ready (DRDY)
        6. 9.5.1.6 Timeout
      2. 9.5.2 Data Format
      3. 9.5.3 Commands
        1. 9.5.3.1  NOP
        2. 9.5.3.2  WAKEUP
        3. 9.5.3.3  POWERDOWN
        4. 9.5.3.4  RESET
        5. 9.5.3.5  START
        6. 9.5.3.6  STOP
        7. 9.5.3.7  SYOCAL
        8. 9.5.3.8  SYGCAL
        9. 9.5.3.9  SFOCAL
        10. 9.5.3.10 RDATA
        11. 9.5.3.11 RREG
        12. 9.5.3.12 WREG
      4. 9.5.4 Interfacing with Multiple Devices
    6. 9.6 Register Map
      1. 9.6.1 Configuration Registers
      2. 9.6.2 Register Descriptions
        1. 9.6.2.1  Device ID Register (address = 00h) [reset = xxh]
          1. Table 16. Device ID (ID) Register Field Descriptions
        2. 9.6.2.2  Device Status Register (address = 01h) [reset = 80h]
          1. Table 17. Device Status (STATUS) Register Field Descriptions
        3. 9.6.2.3  Input Multiplexer Register (address = 02h) [reset = 01h]
          1. Table 18. Input Multiplexer (INPMUX) Register Field Descriptions
        4. 9.6.2.4  Gain Setting Register (address = 03h) [reset = 00h]
          1. Table 19. Gain Setting (PGA) Register Field Descriptions
        5. 9.6.2.5  Data Rate Register (address = 04h) [reset = 14h]
          1. Table 20. Data Rate (DATARATE) Register Field Descriptions
        6. 9.6.2.6  Reference Control Register (address = 05h) [reset = 10h]
          1. Table 21. Reference Control (REF) Register Field Descriptions
        7. 9.6.2.7  Excitation Current Register 1 (address = 06h) [reset = 00h]
          1. Table 22. Excitation Current Register 1 (IDACMAG) Register Field Descriptions
        8. 9.6.2.8  Excitation Current Register 2 (address = 07h) [reset = FFh]
          1. Table 23. Excitation Current Register 2 (IDACMUX) Register Field Descriptions
        9. 9.6.2.9  Sensor Biasing Register (address = 08h) [reset = 00h]
          1. Table 24. Sensor Biasing (VBIAS) Register Field Descriptions
        10. 9.6.2.10 System Control Register (address = 09h) [reset = 10h]
          1. Table 25. System Control (SYS) Register Field Descriptions
        11. 9.6.2.11 Reserved Register (address = 0Ah) [reset = 00h]
          1. Table 26. Reserved Register Field Descriptions
        12. 9.6.2.12 Offset Calibration Register 1 (address = 0Bh) [reset = 00h]
          1. Table 27. Offset Calibration Register 1 (OFCAL0) Register Field Descriptions
        13. 9.6.2.13 Offset Calibration Register 2 (address = 0Ch) [reset = 00h]
          1. Table 28. Offset Calibration Register 2 (OFCAL1) Register Field Descriptions
        14. 9.6.2.14 Reserved Register (address = 0Dh) [reset = 00h]
          1. Table 29. Reserved Register Field Descriptions
        15. 9.6.2.15 Gain Calibration Register 1 (address = 0Eh) [reset = 00h]
          1. Table 30. Gain Calibration Register 1 (FSCAL0) Field Descriptions
        16. 9.6.2.16 Gain Calibration Register 2 (address = 0Fh) [reset = 40h]
          1. Table 31. Gain Calibration Register 2 (FSCAL1) Field Descriptions
        17. 9.6.2.17 GPIO Data Register (address = 10h) [reset = 00h]
          1. Table 32. GPIO Data (GPIODAT) Register Field Descriptions
        18. 9.6.2.18 GPIO Configuration Register (address = 11h) [reset = 00h]
          1. Table 33. GPIO Configuration (GPIOCON) Register Field Descriptions
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Serial Interface Connections
      2. 10.1.2 Analog Input Filtering
      3. 10.1.3 External Reference and Ratiometric Measurements
      4. 10.1.4 Establishing a Proper Input Voltage
      5. 10.1.5 Unused Inputs and Outputs
      6. 10.1.6 Pseudo Code Example
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Register Settings
      3. 10.2.3 Application Curves
    3. 10.3 What To Do and What Not To Do
  11. 11Power Supply Recommendations
    1. 11.1 Power Supplies
    2. 11.2 Power-Supply Sequencing
    3. 11.3 Power-On Reset
    4. 11.4 Power-Supply Decoupling
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Development Support
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Related Links
    4. 13.4 Receiving Notification of Documentation Updates
    5. 13.5 Community Resources
    6. 13.6 Trademarks
    7. 13.7 Electrostatic Discharge Caution
    8. 13.8 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RHB|32
  • PBS|32
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Layout Guidelines

Employing best design practices is recommended when laying out a printed-circuit board (PCB) for both analog and digital components. This recommendation generally means that the layout separates analog components [such as ADCs, amplifiers, references, digital-to-analog converters (DACs), and analog MUXs] from digital components [such as microcontrollers, complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), radio frequency (RF) transceivers, universal serial bus (USB) transceivers, and switching regulators]. Figure 103 shows an example of good component placement. Although Figure 103 provides a good example of component placement, the best placement for each application is unique to the geometries, components, and PCB fabrication capabilities employed. That is, there is no single layout that is perfect for every design and careful consideration must always be used when designing with any analog component.

ADS114S06B ADS114S08B ai_comp_plcmt_bas501.gifFigure 103. System Component Placement

The following basic recommendations for layout of the ADS114S0xB help achieve the best possible performance of the ADC. A good design can be ruined with a bad circuit layout.

  • Separate analog and digital signals. To start, partition the board into analog and digital sections where the layout permits. Route digital lines away from analog lines. This prevents digital noise from coupling back into analog signals.
  • The ground plane can be split into an analog plane (AGND) and digital plane (DGND), but this splitting is not necessary. Place digital signals over the digital plane, and analog signals over the analog plane. As a final step in the layout, the split between the analog and digital grounds must be connected to together at the ADC.
  • Fill void areas on signal layers with ground fill.
  • Provide good ground return paths. Signal return currents will flow on the path of least impedance. If the ground plane is cut or has other traces that block the current from flowing right next to the signal trace, another path must be found to return to the source and complete the circuit. If forced into a larger path, the chance that the signal radiates increases. Sensitive signals are more susceptible to EMI interference.
  • Use bypass capacitors on supplies to reduce high-frequency noise. Do not place vias between bypass capacitors and the active device. Placing the bypass capacitors on the same layer as close to the active device yields the best results.
  • Consider the resistance and inductance of the routing. Often, traces for the inputs have resistances that react with the input bias current and cause an added error voltage. Reducing the loop area enclosed by the source signal and the return current reduces the inductance in the path. Reducing the inductance reduces the EMI pickup and reduces the high-frequency impedance at the input of the device.
  • Watch for parasitic thermocouples in the layout. Dissimilar metals going from each analog input to the sensor can create a parasitic themocouple that can add an offset to the measurement. Differential inputs must be matched for both the inputs going to the measurement source.
  • Analog inputs with differential connections must have a capacitor placed differentially across the inputs. Best input combinations for differential measurements use adjacent analog input lines (such as AIN0, AIN1 and AIN2, AIN3). The differential capacitors must be of high quality. The best ceramic chip capacitors are C0G (NPO) that have stable properties and low noise characteristics.