Texas Instruments MSP430F67681AIPEUR

Overview

MSP430F67681AIPEUR from Texas Instruments is a polyphase metering SoC designed for high-accuracy energy measurement in 3-phase utility meters. It integrates six 24-bit sigma-delta ADCs, a 25-MHz CPU with 32-bit multiplier, 512KB flash/16KB RAM, LCD controller (320 segments), and dual eUSCI_A/B interfaces. It meets ANSI C12.20 and IEC 62053 standards and supports shunt/CT/Rogowski sensor inputs for phase current accuracy < 0.1% over 2000:1 dynamic range.

For engineers reviewing the MSP430F67681AIPEUR datasheet, MSP430F67681AIPEUR pinout, MSP430F67681AIPEUR application, or MSP430F67681AIPEUR equivalent, key selection criteria include its 128-pin LQFP package, dedicated pulse output pins for active/reactive energy calibration, RTC with tamper detection, ultra-low-power LPM3.5 mode (0.34 µA), and support for 40–70 Hz line frequency with single-point calibration.

Technical Context

The MSP430F67681AIPEUR implements a metrology-specific architecture with independent SD24_B sigma-delta modulators per phase channel, each feeding digital filters and metrology computation engines. Its analog front end includes programmable gain, digital phase correction for CTs, and temperature-compensated energy accumulation - all executed in real time by the integrated CPU and DMA.

Digital subsystems include three-channel DMA for zero-CPU-overhead ADC data transfer, four 16-bit timers with nine capture/compare registers, six eUSCI modules (four UART/IrDA/SPI + two SPI/I²C), and hardware CRC-16. Power management supports automatic supply switching between AC mains and backup battery, enabling uninterrupted RTC and LCD operation during outages.

Key Specifications

Pinout & Package

Package: 128-pin LQFP (PEU), 20 mm × 14 mm body size, 0.5 mm pitch. Requires external connection of VDSYS1–VDSYS2 and VASYS1–VASYS2 pairs for proper power domain isolation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar polyphase metering applications.

Compared with MSP430F67691AIPEUR, the MSP430F67681AIPEUR trades one metrology ADC channel and half the RAM for lower cost and identical footprint; versus MSP430F67681AIPZ, it delivers 28 additional GPIOs and full 6-channel SD24_B support in the larger PEU package - critical for complex HMI and multi-sensor deployments.

Availability

MSP430F67681AIPEUR is available at Aetrix Electronics and suitable for 3-phase electronic watt-hour meters, smart grid data concentrators, and industrial energy monitoring gateways requiring stable component supply, long-term lifecycle support, and TI-qualified metrology performance.

Supply support for MSP430F67681AIPEUR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company specializing in analog, embedded processing, and connectivity technologies, with leadership in low-power microcontrollers and precision metrology solutions.

The MSP430F67681AIPEUR belongs to TI's Metrology and Monitoring MCU portfolio, engineered specifically for revenue-grade energy measurement in utility and building automation applications - emphasizing accuracy, security, and ultra-low-power operation.

FAQ

What is the maximum number of independent 24-bit ADC channels supported by the MSP430F67681AIPEUR?

The MSP430F67681AIPEUR integrates six independent 24-bit sigma-delta ADC channels (SD24_B) - sufficient for three-phase voltage/current measurement plus neutral or auxiliary sensing. This matches the device's designation in the F676x1A family, confirmed in Table 3-1 of SLAS983A. Each channel supports differential inputs, programmable gain, and digital filtering optimized for metrology accuracy.

Does the MSP430F67681AIPEUR support hardware-based anti-tampering features?

Yes, the MSP430F67681AIPEUR includes integrated security modules for anti-tamper functionality: RTC tamper detection on dedicated pins, password-protected register access, hardware AES-128 encryption, and secure boot. These features are explicitly documented in Section 1.1 (Features) and Section 6.11.18 (RTC_C) of the datasheet, enabling compliance with IEC 62053-31 security requirements.

What is the lowest power consumption mode available for RTC operation on the MSP430F67681AIPEUR?

The MSP430F67681AIPEUR achieves 0.34 µA in RTC mode (LPM3.5) at 3 V with 32.768 kHz crystal running - verified in Section 5.5 of SLAS983A. This mode retains RTC timekeeping, 32KB RAM, and crystal oscillator while disabling CPU and most peripherals, enabling >10-year battery life in backup operation.

Can the MSP430F67681AIPEUR drive a 320-segment LCD directly without external components?

Yes, the MSP430F67681AIPEUR includes an integrated LCD_C controller supporting up to 320 segments (8 commons × 40 segments) with internal charge pump and contrast control. Section 1.1 confirms "LCD Driver With Contrast Control for up to 320 Segments", and electrical specs in Section 5.15 validate operation across temperature and voltage ranges without external bias circuitry.

Which communication interfaces does the MSP430F67681AIPEUR provide for smart meter connectivity?

The MSP430F67681AIPEUR provides six enhanced Universal Serial Communication Interfaces: four eUSCI_A modules (configurable as UART, IrDA, or SPI) and two eUSCI_B modules (configurable as SPI or I²C). These support concurrent connections to PLC modems (SPI), optical ports (UART), HAN radios (UART/I²C), and sensor hubs (I²C), as detailed in Section 1.1 and Table 3-1.