SBAS710A September   2016  – June 2017 ADS9120

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  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: Conversion Cycle
    7. 6.7  Timing Requirements: Asynchronous Reset, NAP, and PD
    8. 6.8  Timing Requirements: SPI-Compatible Serial Interface
    9. 6.9  Timing Requirements: Source-Synchronous Serial Interface (External Clock)
    10. 6.10 Timing Requirements: Source-Synchronous Serial Interface (Internal Clock)
    11. 6.11 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Converter Module
        1. 7.3.1.1 Sample-and-Hold Circuit
        2. 7.3.1.2 External Reference Source
        3. 7.3.1.3 Internal Oscillator
        4. 7.3.1.4 ADC Transfer Function
      2. 7.3.2 Interface Module
    4. 7.4 Device Functional Modes
      1. 7.4.1 RST State
      2. 7.4.2 ACQ State
      3. 7.4.3 CNV State
    5. 7.5 Programming
      1. 7.5.1 Data Transfer Frame
      2. 7.5.2 Interleaving Conversion Cycles and Data Transfer Frames
      3. 7.5.3 Data Transfer Protocols
        1. 7.5.3.1 Protocols for Configuring the Device
        2. 7.5.3.2 Protocols for Reading From the Device
          1. 7.5.3.2.1 Legacy, SPI-Compatible (SYS-xy-S) Protocols
          2. 7.5.3.2.2 SPI-Compatible Protocols with Bus Width Options
          3. 7.5.3.2.3 Source-Synchronous (SRC) Protocols
            1. 7.5.3.2.3.1 Output Clock Source Options with SRC Protocols
            2. 7.5.3.2.3.2 Bus Width Options with SRC Protocols
            3. 7.5.3.2.3.3 Output Data Rate Options with SRC Protocols
      4. 7.5.4 Device Setup
        1. 7.5.4.1 Single Device: All multiSPI™ Options
        2. 7.5.4.2 Single Device: Minimum Pins for a Standard SPI Interface
        3. 7.5.4.3 Multiple Devices: Daisy-Chain Topology
        4. 7.5.4.4 Multiple Devices: Star Topology
    6. 7.6 Register Maps
      1. 7.6.1 Device Configuration and Register Maps
        1. 7.6.1.1 PD_CNTL Register (address = 010h)
        2. 7.6.1.2 SDI_CNTL Register (address = 014h)
        3. 7.6.1.3 SDO_CNTL Register (address = 018h)
        4. 7.6.1.4 DATA_CNTL Register (address = 01Ch)
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 ADC Input Driver
      2. 8.1.2 Input Amplifier Selection
      3. 8.1.3 Charge Kickback Filter
      4. 8.1.4 ADC Reference Driver
    2. 8.2 Typical Application
      1. 8.2.1 Data Acquisition (DAQ) Circuit for Lowest Distortion and Noise Performance With Differential Input
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 DAQ Circuit With FDA Input Driver and Single-Ended or Differential Input
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power-Supply Recommendations
    1. 9.1 Power-Supply Decoupling
    2. 9.2 Power Saving
      1. 9.2.1 NAP Mode
      2. 9.2.2 PD Mode
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Signal Path
      2. 10.1.2 Grounding and PCB Stack-Up
      3. 10.1.3 Decoupling of Power Supplies
      4. 10.1.4 Reference Decoupling
      5. 10.1.5 Differential Input Decoupling
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

1 Features

  • Sample Rate: 2.5 MSPS
  • No Latency Output
  • Excellent DC and AC Performance:
    • INL: ±0.25 LSB
    • DNL: ±0.6 LSB
    • SNR: 96 dB, THD: –118 dB
  • Wide Input Range:
    • Unipolar Differential Input Range: ±VREF
    • VREF Input Range: 2.5 V to 5 V,
      Independent of AVDD
  • Low-Power Dissipation:
    • 9 mW at 2.5 MSPS (AVDD Only)
    • 15.5 mW at 2.5 MSPS (Total)
    • Flexible Low-Power Modes Enable Power Scaling with Throughput
  • Enhanced-SPI (multiSPI™) Digital Interface
  • JESD8-7A-Compliant Digital I/O at 1.8-V DVDD
  • Fully-Specified Over Extended Temperature Range: –40°C to +125°C
  • Small Footprint: 4-mm × 4-mm VQFN

2 Applications

  • Test and Measurement
  • Motor Control
  • Medical Imaging
  • High-Precision, High-Speed Industrial

3 Description

The ADS9120 is a 16-bit, 2.5-MSPS, successive approximation register (SAR) analog-to-digital converter (ADC) with enhanced performance features. The high throughput enables developers to oversample the input signal to improve dynamic range and accuracy of the measurement. The ADS9110 is a pin-compatible, 18-bit, 2-MSPS variant of the ADS9120.

The ADS9120 boosts analog performance while maintaining high-resolution data transfer by using TI’s enhanced SPI feature. Enhanced SPI enables the ADS9120 to achieve high throughput at lower clock speeds, thereby simplifying board layout and lowering system cost.

Enhanced SPI also simplifies the host clocking-in of data, thereby making the device ideal for applications involving FPGAs and DSPs. The ADS9120 is compatible with a standard SPI Interface. The ADS9120 has an internal data parity feature that can be appended to the ADC data output. ADC data validation by the host, using parity bits, improves system reliability.

The device supports JESD8-7A compliant I/Os, the extended industrial temperature range, and is offered in a space-saving, 4-mm × 4-mm, VQFN package.

SPI Interface Clock at Full Throughput(1)

PART NUMBER 3-WIRE SPI 3-WIRE ENHANCED-SPI
ADS9120 200 MHz 45 MHz
  1. For all features of the enhanced SPI, see the Interface Module section.

Ease of System Design with ADS9120

ADS9120 multi_adc_design_9120.gif