SBAS563E December   2011  – December 2022 ADS1113-Q1 , ADS1114-Q1 , ADS1115-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
    1.     Device Comparison Table
  5. 5 Pin Configuration and Functions
  6. 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: I2C
    7. 6.7 Timing Diagram
    8. 6.8 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Noise Performance
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Multiplexer
      2. 8.3.2 Analog Inputs
      3. 8.3.3 Full-Scale Range (FSR) and LSB Size
      4. 8.3.4 Voltage Reference
      5. 8.3.5 Oscillator
      6. 8.3.6 Output Data Rate and Conversion Time
      7. 8.3.7 Digital Comparator (ADS1114-Q1 and ADS1115-Q1 Only)
      8. 8.3.8 Conversion Ready Pin (ADS1114-Q1 and ADS1115-Q1 Only)
      9. 8.3.9 SMbus Alert Response
    4. 8.4 Device Functional Modes
      1. 8.4.1 Reset and Power-Up
      2. 8.4.2 Operating Modes
        1. 8.4.2.1 Single-Shot Mode
        2. 8.4.2.2 Continuous-Conversion Mode
      3. 8.4.3 Duty Cycling For Low Power
    5. 8.5 Programming
      1. 8.5.1 I2C Interface
        1. 8.5.1.1 I2C Address Selection
        2. 8.5.1.2 I2C General Call
        3. 8.5.1.3 I2C Speed Modes
      2. 8.5.2 Target Mode Operations
        1. 8.5.2.1 Receive Mode
        2. 8.5.2.2 Transmit Mode
      3. 8.5.3 Writing To and Reading From the Registers
      4. 8.5.4 Data Format
    6. 8.6 Register Map
      1. 8.6.1 Address Pointer Register (address = N/A) [reset = N/A]
      2. 8.6.2 Conversion Register (P[1:0] = 00b) [reset = 0000h]
      3. 8.6.3 Config Register (P[1:0] = 01b) [reset = 8583h]
      4. 8.6.4 Lo_thresh (P[1:0] = 10b) [reset = 8000h] and Hi_thresh (P[1:0] = 11b) [reset = 7FFFh] Registers
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Basic Connections
      2. 9.1.2 Single-Ended Inputs
      3. 9.1.3 Input Protection
      4. 9.1.4 Unused Inputs and Outputs
      5. 9.1.5 Analog Input Filtering
      6. 9.1.6 Connecting Multiple Devices
      7. 9.1.7 Quick-Start Guide
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Shunt Resistor Considerations
        2. 9.2.2.2 Operational Amplifier Considerations
        3. 9.2.2.3 ADC Input Common-Mode Considerations
        4. 9.2.2.4 Resistor (R1, R2, R3, R4) Considerations
        5. 9.2.2.5 Noise and Input Impedance Considerations
        6. 9.2.2.6 First-Order RC Filter Considerations
        7. 9.2.2.7 Circuit Implementation
        8. 9.2.2.8 Results Summary
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Power-Supply Sequencing
      2. 9.3.2 Power-Supply Decoupling
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  10. 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
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

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

9.2 Typical Application

Shunt-based, current-measurement solutions are widely used to monitor load currents. Low-side, current-shunt measurements are independent of the bus voltage because the shunt common-mode voltage is near ground. Figure 9-6 shows an example circuit for a bidirectional, low-side, current-shunt measurement system. The load current is determined by measuring the voltage across the shunt resistor that is amplified and level-shifted by a low-drift operational amplifier, OPA333-Q1. The OPA333-Q1 output voltage is digitized with ADS1115-Q1 and sent to the microcontroller using the I2C interface. This circuit is capable of measuring bidirectional currents flowing through the shunt resistor with great accuracy and precision.

GUID-D54D7EF4-1F50-4BE7-8867-04F13263BD84-low.gifFigure 9-6 Low-Side Current Shunt Monitoring