MAX71637 - Single/Poly-phase ARM CM3 SoCs


  • SoC Integration and Unique Isolation Technique Reduces BOM Cost Without Sacrificing Performance
    • Watt-Hour Accuracy of 0.1% at Up to 5,000:1 Dynamic Range
    • Sample Frequency Configurable; ΣΔ Sample Rate Configurable Up to 9.83MHz
    • Flexible Analog Input Configuration Support Current Transformers, Shunts, or Rogowski Coils
    • 2.7V to 3.6V Operating Voltage
    • Single 32.768kHz Crystal Provides All Operating Clocks
  • ARM Core M3 Application Processor Enables Rapid System Development
    • 1MB Flash
    • 64KB Code RAM
    • 64KB System RAM
    • Six UART Channels
    • Seven Timer Channels
    • I2C Master/Slave Peripheral
    • Three SPI Peripherals
    • Smart Card Interface
  • MAXQ30 Features
    • 64KB Program RAM
    • 8KB Data RAM
    • 16KB Page RAM
    • Four Meter Pulse Outputs (Configurable)
    • Two I2C Master/Slave Peripherals
    • SPI Master/Slave Peripheral
    • 50-Segment, 6-Common LCD Interface
  • Security Features Reduce or Eliminate Common Security Threats
    • Built-In Cryptographic Modules Ensure Communications Are Kept Secure
    • Tamper Detect Inputs Ensure Attempts to Breach the Case Are Recorded and Reported
    • Two Independent Cores Ensures Compliance with All Current and Future Security Requirements
  • Analog Front-End
    • Seven (MAX71637) or Four (MAX71617) 24-Bit ΣΔ A/D Converters
    • Three (MAX71637) or Two (MAX71617) Voltage Inputs
    • Four (MAX71637) or Three (MAX71617) Differential Current Inputs


The MAX71617 is a low-power, single-phase energy measurement system-on-chip (SoC), and the MAX71637 is a low-power polyphase energy measurement SoC. Based on an ARM Cortex®-M3 core, the devices can run modern operating systems that monitor and report energy usage and implement communications stacks. In addition to the main administrative core, the devices include a MAXQ30 CPU core to perform metering functions and a discrete compute engine for the DSP related tasks necessary for accurate energy monitoring and measurement, last cycle analysis, and FFT functions to compute the frequency spectra of the selected channel.

The DSP core provides the following energy and power measurement features in registers:

  • Active energy and power per phase and sum
  • Apparent energy and power per phase and sum
  • Reactive energy and power per phase and sum
  • Line voltage and current RMS
  • Neutral current RMS
  • Current vector sum, three-phase plus neutral
  • Line frequency
  • Fundamental frequency
  • Total harmonics of active power, reactive power, voltage, and currents
  • Security features


  • MID/WELMEC-Compliant Meters
  • Smart and Secure Polyphase Energy Meters
  • Smart and Secure Single-Phase Energy Meters