Texas Instruments MSP430F6721AIPN

Overview

MSP430F6721AIPN from Texas Instruments is an ultra-low-power mixed-signal microcontroller designed for single-phase electronic watt-hour metering applications. It integrates two 24-bit sigma-delta ADCs, a 10-bit 200-ksps ADC with temperature sensor, LCD driver supporting up to 320 segments in 8-mux mode, real-time clock with crystal offset calibration, and three eUSCI_A modules (UART/IrDA/SPI) plus one eUSCI_B (I²C/SPI), all in an 80-pin LQFP package.

For engineers reviewing the MSP430F6721AIPN datasheet, MSP430F6721AIPN pinout, MSP430F6721AIPN application, or MSP430F6721AIPN equivalent, key selection criteria include its dual SD24_B ADC architecture for current/voltage channel separation, low-power RTC operation down to 1.24 µA in LPM3.5, integrated LCD contrast control, and support for auxiliary supply domains enabling isolated backup subsystem operation.

Technical Context

The MSP430F6721AIPN implements a 16-bit RISC CPU with 25-MHz system clock capability and flexible power management including an integrated LDO with programmable core voltage, supply supervision, and brownout reset. Its unified clock system combines FLL stabilization, VLO/REFO internal sources, and 32-kHz XT1 crystal support for precise timing in metering environments.

Peripherals are optimized for metrology: two independent SD24_B converters provide simultaneous high-resolution sampling of voltage and current channels with differential PGA inputs; the 10-bit ADC supports autoscan across six external and two internal channels; and the hardware multiplier enables fast energy computation algorithms without software overhead.

Key Specifications

Pinout & Package

The MSP430F6721AIPN is housed in an 80-pin LQFP (PN) package with 0.5-mm pitch, exposing dedicated analog inputs for SD24_B channels (SD0P0/SD0N0, SD1P0/SD1N0), auxiliary supply pins (AUXVCC1–AUXVCC3), LCD segment/common drivers (COM0–COM7, S0–S39), and multiplexed digital I/O across Ports P1–P9 and PJ.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar metrology microcontroller applications.

Compared with MSP430F6723AIPN, the MSP430F6721AIPN trades Flash/RAM capacity for identical metrology accuracy and lower unit cost; versus MSP430F6721IPN, it adds certified RTC functionality essential for tariff-based billing compliance.

Availability

MSP430F6721AIPN is available at Aetrix Electronics and suitable for single-phase watt-hour meters, utility grid sensor nodes, and portable power quality analyzers requiring stable component supply, long-term lifecycle assurance, and TI-qualified metrology performance.

Supply support for MSP430F6721AIPN 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 and embedded processing technologies, with leadership in low-power design and precision metrology solutions.

The MSP430F67xxA family targets utility metering and energy monitoring applications, integrating high-resolution ADCs, RTC, LCD drivers, and communication peripherals into a single ultra-low-power MCU platform optimized for IEC 62053 and ANSI C12 compliance.

FAQ

What is the maximum sampling rate supported by the SD24_B ADCs in the MSP430F6721AIPN?

The MSP430F6721AIPN's two SD24_B ADCs support up to 256 kSPS aggregate throughput with configurable oversampling ratios. Each converter operates independently, enabling simultaneous sampling of voltage and current channels at up to 128 kSPS per channel-critical for accurate phase-angle measurement in Class 0.5 meters per IEC 62053-21.

Does the MSP430F6721AIPN support hardware-accelerated energy computation?

Yes, the MSP430F6721AIPN includes a 32-bit hardware multiplier and three-channel DMA that enable cycle-efficient execution of IEEE 1459-compliant active/reactive/apparent energy calculations. The SD24_B data can be streamed directly to RAM via DMA, and the multiplier performs multiply-accumulate operations on sampled data without CPU intervention-reducing active-mode time and power consumption.

How does the MSP430F6721AIPN ensure RTC accuracy over temperature and time?

The MSP430F6721AIPN implements password-protected RTC calibration with both crystal offset correction and temperature compensation. Using its internal temperature sensor and factory-trimmed coefficients stored in TLV memory, it dynamically adjusts the 32-kHz oscillator frequency to maintain ±20 ppm accuracy from –40°C to +85°C-meeting IEC 62053-62 long-term drift requirements for revenue metering.

Can the MSP430F6721AIPN drive a 320-segment LCD without external components?

Yes, the MSP430F6721AIPN's integrated LCD_C module supports up to 320 segments in 8-mux configuration with programmable contrast control, internal charge pump, and adjustable bias voltage generation. No external capacitors or resistor networks are required beyond the mandatory LCDCAP pin capacitor (tied to DVSS if unused), reducing BOM count and board space in compact meter designs.

What debug interface does the MSP430F6721AIPN use, and is JTAG supported?

The MSP430F6721AIPN supports both Spy-Bi-Wire (SBW) and full 4-wire JTAG via pins TEST/SBWTCK (pin 75), PJ.0–PJ.3 (pins 76–79), and RST/NMI (pin 80). SBW is the default and recommended interface for production programming and debugging, offering reduced pin count and compatibility with TI's MSP-FET and LaunchPad tools-enabling seamless firmware updates and real-time trace in meter development.