MAX35104

Gas Flow Meter SoC

Industry's First Integrated SOC Designed to Address the Unique Requirements of Natural Gas Meters


Description

The MAX35104 is a gas flow meter system-on-chip (SoC) targeted as an analog front-end solution for the ultrasonic gas meter and medical ventilator markets. With a time measurement accuracy of 700ps and automatic differential time of flight (TOF), the device makes for simplified computation of gaseous flow.

Power consumption is the lowest available with ultra-low 62µA time-of-flight measurement and 125nA duty-cycled temperature measurement. Multi-hit (up to six per wave) capability with stop-enable windowing allows the device to be fine-tuned for the application. Internal analog switches, a configurable three-stage integrated operational amplifier chain amplifier, and an ultra-low input offset comparator provide the analog interface and control for a minimal electrical bill of material solution. A programmable high-voltage (up to 30V) pulse launcher provides up to 19dB of transducer launch amplitude adjustment to compensate for transducer aging and temperature, pressure, humidity affects. Early edge detection ensures measurements are made with consistent wave patterns to greatly improve accuracy and eliminate erroneous measurements. Built-in arithmetic logic unit provides TOF difference measurements and programmable receiver hit accumulators to minimize the host microprocessor access. For temperature measurement, the device supports a single 2-wire PT1000 platinum resistive temperature detector (RTD) or NTC thermistor. A simple 4-wire SPI interface allows any microcontroller to effectively configure the device for its intended measurement.
MAX35104: Block Diagram MAX35104: Block Diagram Enlarge+

Key Features

  • High Accuracy Flow Measurement for Billing and Leak Detection
    • Time-to-Digital Accuracy Down to 700ps Measurement Range Up to 400μs
    • 2 Channels: Single-Stop Channel
  • High Accuracy Temperature Measurement for Precise Flow Calculations
    • One 2-Wire Sensor: PT1000, PT500 RTD, and Thermistor Support
  • Maximizes Battery Life with Low Device and Overall System Power
    • Ultra-Low 62µA TOF Measurement and 125nA Duty-Cycled Temperature Measurement
    • Event Timing Mode with Randomizer Reduces Host µC Overhead to Minimize System Power Consumption
    • 2.3V to 3.6V Single-Supply Operation
  • High Integration Solution Minimizes Parts Count and Reduces BOM Cost
    • Built-In Real-Time Clock
    • Small, 5mm x 5mm, 40-Pin TQFN Package
    • -40°C to +85°C Operation
  • Applications/Uses

    • Medical Ventilators
    • Ultrasonic Gas Meters
    Part Number Sensing Element PGA Gain Calibration Method Output Type ICC
    (mA)
    Interface VSUPPLY
    (V)
    Package/Pins Budgetary
    Price
    typ See Notes
    MAX35104 NEW!
    RTD
    Ultrasonic Piezoelectric Transducer
    Ultrasonic Transducer
    10 to 29.95 (16 gains) External microcontroller Digital 0.006 SPI 2.3 to 3.6
    TQFN/40
    $6.31 @1k
    See All Sensor Signal Conditioners (12)
    Pricing Notes:
    This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.


    MAX35104EVKIT: Evaluation Kit for the MAX35104

    Quality and Environmental Data

    Request Reliability Report for: MAX35104 
    Lead-Free Package Tin (Sn) Whisker Reports

    Related Resources


    MAX35104
    Gas Flow Meter SoC

  • High Accuracy Flow Measurement for Billing and Leak Detection
    • Time-to-Digital Accuracy Down to 700ps Measurement Range Up to 400μs
    • 2 Channels: Single-Stop Channel
  • High Accuracy Temperature Measurement for Precise Flow Calculations
    • One 2-Wire Sensor: PT1000, PT500 RTD, and Thermistor Support
  • Maximizes Battery Life with Low Device and Overall System Power
    • Ultra-Low 62µA TOF Measurement and 125nA Duty-Cycled Temperature Measurement
    • Event Timing Mode with Randomizer Reduces Host µC Overhead to Minimize System Power Consumption
    • 2.3V to 3.6V Single-Supply Operation


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