GENERAL DESCRIPTION
The 71M6545/71M6545H metrology processors are based on Teridian’s 4th-generation metering architecture supporting the 71M6xxx series of isolated current sensing products that offer drastic reduction in component count, immunity to magnetic tampering, and unparalleled reliability. The 71M6545/71M6545H integrate our Single Converter Technology® with a 22-bit delta-sigma ADC, a customizable 32-bit computation engine (CE) for core metrology functions, as well as a user-programmable 8051-compatible application processor (MPU) core with up to 64KB flash and up to 5KB RAM.
An external host processor can access metrology functions di-rectly through the SPI™ interface, or alternatively through the embedded MPU core in applications requiring metrology data capture, storage, and preprocessing within the metrology subsystem. In addition, the devices integrate an RTC, DIO, and UART. A complete array of ICE and development tools, programming libraries, and reference designs enable rapid development and certification of meters that meet all ANSI and IEC electricity metering standards worldwide.

FEATURES
• Up to < 0.1% Accuracy Over 2000:1 Current Range
• Exceeds IEC 62053/ANSI C12.20 Standards
• Seven Sensor Inputs with Neutral Current Measurement, Differential Mode Selectable for Current Inputs
• Selectable Gain of 1 or 8 for One Current Input to Support Shunts
• High-Speed Wh/VARh Pulse Outputs with Programmable Width
• Flash/RAM Size
32KB/3KB (71M6545)
64KB/5KB (71M6545H)
• Up to Four Pulse Outputs with Pulse Count
• Four-Quadrant Metering, Phase Sequencing
• Digital Temperature Compensation
Metrology Compensation
Accurate RTC for TOU Functions with Automatic Temperature Compensation for Crystal in All Power Modes
• Independent 32-Bit Compute Engine
• 46–64Hz Line Frequency Range with the Same Calibration
• Phase Compensation (±7°)
• 1μA Supply Current in Sleep Mode
• Flash Security
• In-System Program Update
• 8-Bit MPU (80515), Up to 5 MIPS, for Optional Implementation of Postprocessing and Host Support Functions (Optional Use)
• Up to 29 DIO Pins
• Hardware Watchdog Timer (WDT)
• I2C/MICROWIRE® EEPROM Interface
• SPI Interface for Host:
Full Access to Shared Memory Space
Flash Program Capability
• UART
• Industrial Temperature Range
• 64-Pin Lead(Pb)-Free LQFP Package