SNAS510S January   2011  – January 2016 LMP90097 , LMP90098 , LMP90099 , LMP90100

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Typical Application Schematic
  5. 5 Revision History
  6. 6 Description (continued)
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1  Absolute Maximum Ratings
    2. 8.2  ESD Ratings
    3. 8.3  Recommended Operating Conditions
    4. 8.4  Thermal Information
    5. 8.5  Electrical Characteristics
    6. 8.6  SPI Timing Requirements
    7. 8.7  CBS Setup and Hold Timing Requirements
    8. 8.8  SCLK and SDI Timing Requirements
    9. 8.9  SDO Timing Requirements
    10. 8.10 SDO and DRDYB Timing Requirements
    11. 8.11 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 True Continuous Background Calibration
      2. 9.3.2 Continuous Background Sensor Diagnostics
      3. 9.3.3 Flexible Input MUX Channels
      4. 9.3.4 Programmable Gain Amplifiers (FGA and PGA)
      5. 9.3.5 Excitation Current Sources (IB1 and IB2) - LMP90100/LMP90098
      6. 9.3.6 Signal Path
        1. 9.3.6.1 Reference Input (VREF)
        2. 9.3.6.2 Flexible Input MUX (VIN)
        3. 9.3.6.3 Selectable Gains (FGA and PGA)
        4. 9.3.6.4 Buffer (BUFF)
        5. 9.3.6.5 Internal/External CLK Selection
        6. 9.3.6.6 Programmable ODRs
        7. 9.3.6.7 Digital Filter
        8. 9.3.6.8 GPIO (D0-D6)
      7. 9.3.7 Calibration
        1. 9.3.7.1 Background Calibration
          1. 9.3.7.1.1 Types of Background Calibration
          2. 9.3.7.1.2 Using Background Calibration
        2. 9.3.7.2 System Calibration
          1. 9.3.7.2.1 System Calibration Offset Coefficient Determination Mode
          2. 9.3.7.2.2 System Calibration Gain Coefficient Determination Mode
          3. 9.3.7.2.3 Post-Calibration Scaling
      8. 9.3.8 Sensor Interface
        1. 9.3.8.1 IB1 and IB2 - Excitation Currents
        2. 9.3.8.2 Burnout Currents
          1. 9.3.8.2.1 Burnout Current Injection
        3. 9.3.8.3 Sensor Diagnostic Flags
          1. 9.3.8.3.1 SHORT_THLD_FLAG
          2. 9.3.8.3.2 RAILS_FLAG
          3. 9.3.8.3.3 POR_AFT_LST_RD:
          4. 9.3.8.3.4 OFLO_FLAGS
          5. 9.3.8.3.5 SAMPLED_CH
      9. 9.3.9 RESET and RESTART
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power Management
      2. 9.4.2 Channels Scan Mode
        1. 9.4.2.1 ScanMode0: Single-Channel Continuous Conversion
        2. 9.4.2.2 ScanMode1: Multiple-Channels Single Scan
        3. 9.4.2.3 ScanMode2: Multiple-Channels Continuous Scan
        4. 9.4.2.4 ScanMode3: Multiple-Channels Continuous Scan with Burnout Currents
    5. 9.5 Programming
      1. 9.5.1  General Rules
      2. 9.5.2  Serial Digital Interface
      3. 9.5.3  Register Address (ADDR)
      4. 9.5.4  Register Read/Write Protocol
      5. 9.5.5  Streaming
      6. 9.5.6  CSB - Chip Select Bar
      7. 9.5.7  SPI Reset
      8. 9.5.8  DRDYB - Data Ready Bar
      9. 9.5.9  DRDYB Case1: Combining SDO/DRDYB with SDO_DRDYB_DRIVER = 0x00
      10. 9.5.10 DRDYB Case2: Combining SDO/DRDYB with SDO_DRDYB_DRIVER = 0x03
      11. 9.5.11 DRDYB Case3: Routing DRDYB to D6
      12. 9.5.12 Data Only Read Transaction
      13. 9.5.13 Cyclic Redundancy Check (CRC)
      14. 9.5.14 Register Read/Write Examples
        1. 9.5.14.1 Writing To Register Examples
        2. 9.5.14.2 Reading From Register Example
      15. 9.5.15 Streaming Examples
        1. 9.5.15.1 Normal Streaming Example
        2. 9.5.15.2 Controlled Streaming Example
    6. 9.6 Register Maps
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Quick Start
      2. 10.1.2 ADC_DOUT Calculation
    2. 10.2 Typical Applications
      1. 10.2.1 3-Wire RTD Using 2 Current Sources
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
        3. 10.2.1.3 Application Curve
      2. 10.2.2 3-Wire RTD Using 1 Current Source
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedure
        3. 10.2.2.3 Application Curve
      3. 10.2.3 Thermocouple with Cold Junction Compensation
        1. 10.2.3.1 Design Requirements
        2. 10.2.3.2 Detailed Design Procedure
      4. 10.2.4 Application Curve
  11. 11Power Supply Recommendations
    1. 11.1 VA and VIO
    2. 11.2 VREF
  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 Device Nomenclature
        1. 13.1.1.1 Specific Definitions
    2. 13.2 Related Links
    3. 13.3 Community Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • 24-Bit, Low-Power Sigma-Delta ADC
  • True Continuous Background Calibration at all Gains
  • In-Place System Calibration Using Expected Value Programming
  • Low-Noise Programmable Gain (1x to 128x)
  • Continuous Background Open / Short and Out-of-Range Sensor Diagnostics
  • 8 Output Data Rates (ODR) With Single-Cycle Settling
  • 2 Matched Excitation Current Sources From 100 µA to 1000 µA (LMP90100/LMP90098)
  • 4-DIFF / 7-SE Inputs (LMP90100/LMP90099)
  • 2-DIFF / 4-SE Inputs (LMP90098/LMP90097)
  • 7 General-Purpose Input/Output Pins
  • Chopper-Stabilized Buffer for Low Offset
  • SPI 4/3-wire With CRC Data Link Error Detection
  • 50-Hz to 60-Hz Line Rejection at ODR
    ≤13.42 SPS
  • Independent Gain and ODR Selection per Channel
  • Supported by WEBENCH® Sensor AFE Designer
  • Automatic Channel Sequencer
  • Key Specifications
    • ENOB/NFR Up to 21.5/19 Bits
    • Offset Error (Typical) 8.4 nV
    • Gain Error (Typical) 7 ppm
    • Total Noise < 10 µV-rms
    • Integral Nonlinearity (INL Maximum) ± 15 ppm of FSR
    • Output Data Rates (ODR) 1.6775 - 214.65 SPS
    • Analog Voltage, VA 2.85 to 5.5 V
    • Operating Temp Range –40°C to 125°C
    • 28-Pin HTSSOP Exposed Pad

2 Applications

  • Temperature and Pressure Transmitters
  • Strain Gauge Interface
  • Industrial Process Control

3 Description

The LMP90xxx is a highly integrated, multichannel, low-power, 24-bit Sensor AFEs. The devices features a precision, 24-bit Sigma-Delta analog-to-digital converter (ADC) with a low-noise programmable gain amplifier and a fully differential high-impedance analog input multiplexer. A true continuous background calibration feature allows calibration at all gains and output data rates without interrupting the signal path. The background calibration feature essentially eliminates gain and offset errors across temperature and time, providing measurement accuracy without sacrificing speed and power consumption.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LMP90097 HTSSOP (28) 9.70 mm x 4.40 mm
LMP90098
LMP90099
LMP90100
  1. For all available packages, see the orderable addendum at the end of the datasheet.

4 Typical Application Schematic

LMP90100 LMP90099 LMP90098 LMP90097 30139574.gif