Texas Instruments MSP430F6721AIPNR

Overview

MSP430F6721AIPNR 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, LCD driver supporting up to 320 segments in 8-mux mode, three eUSCI_A modules (UART/IrDA/SPI), one eUSCI_B module (I²C/SPI), and operates from 1.8 V to 3.6 V with standby current as low as 1.7 µA at 3.0 V.

For engineers reviewing the MSP430F6721AIPNR datasheet, MSP430F6721AIPNR pinout, MSP430F6721AIPNR application, or MSP430F6721AIPNR equivalent, key selection criteria include its dual SD24_B ADC architecture for simultaneous voltage/current measurement, RTC with crystal offset calibration, integrated LCD contrast control, and LQFP-80 package compatibility with utility meter reference designs such as EVM430-F6736.

Technical Context

The MSP430F6721AIPNR implements a 16-bit RISC CPU with 25-MHz system clock capability, unified clock system featuring FLL stabilization, VLO and REFO internal sources, and XT1 32-kHz crystal support. Its power management includes an integrated LDO with programmable core voltage, supply supervision, and dual auxiliary supply domains for backup subsystem isolation.

Peripherals are organized around four 16-bit Timer_A modules (one with three capture/compare registers, three with two each), three-channel DMA, hardware multiplier supporting 32-bit operations, and dedicated SD24_B input pins (SD0P0/SD0N0, SD1P0/SD1N0) with analog buffer types referenced to AVCC - confirming its role in high-precision metrology signal chains requiring differential PGA inputs and temperature-compensated RTC operation.

Key Specifications

Pinout & Package

Package: 80-pin LQFP (PN), 12 mm × 12 mm body size, surface-mount, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MSP430F6723AIPNR and MSP430F6720AIPNR, the MSP430F6721AIPNR provides optimal balance of memory (32 KB flash/2 KB RAM), metrology precision, and low-power operation - making it ideal for mid-tier single-phase meters requiring field-upgrade capability without over-provisioning resources.

Availability

MSP430F6721AIPNR is available at Aetrix Electronics and suitable for single-phase electronic watt-hour meters, utility AMI endpoints, and portable energy monitoring gateways requiring stable component supply across multi-year production cycles.

Supply support for MSP430F6721AIPNR 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 delivering analog and embedded processing solutions, with leadership in low-power microcontrollers and precision analog front-ends.

The MSP430F672xA product line is engineered specifically for utility metering applications, integrating metrology-grade ADCs, RTC, LCD drivers, and ultra-low-power operation to meet IEC 62053 and ANSI C12 standards.

FAQ

What is the maximum system clock frequency supported by the MSP430F6721AIPNR?

The MSP430F6721AIPNR supports a maximum system clock frequency of 25 MHz, enabled by its integrated FLL control loop and DCO oscillator. This allows real-time execution of complex metrology algorithms-including RMS, harmonic analysis, and tariff calculations-while maintaining sub-1 µs interrupt latency. The 25-MHz capability is confirmed in the device description section of the SLASE46A datasheet and applies directly to the MSP430F6721AIPNR variant.

Does the MSP430F6721AIPNR include hardware support for LCD display driving?

Yes, the MSP430F6721AIPNR integrates the LCD_C peripheral with built-in contrast control, supporting up to 320 segments in 8-mux mode. It requires only an external LCDCAP capacitor (connected to pin 29) and no external bias resistors or charge pumps. This capability is explicitly documented in the "Features" and "Detailed Description" sections of the SLASE46A datasheet and is functionally identical across all MSP430F672xA variants, including the MSP430F6721AIPNR.

How many sigma-delta ADC channels does the MSP430F6721AIPNR provide, and what are their input configurations?

The MSP430F6721AIPNR provides two independent 24-bit sigma-delta ADCs (SD24_B), each with differential PGA inputs. Channel 0 uses pins SD0P0/SD0N0; channel 1 uses SD1P0/SD1N0. Both accept analog inputs referenced to AVCC/AVSS and support programmable gain (1×–32×). This configuration is confirmed in Table 3-1 (Device Comparison) and Section 1.1 (Features) of the SLASE46A datasheet for the MSP430F6721AIPNR.

What low-power modes are available on the MSP430F6721AIPNR, and what is the typical current draw in LPM3?

The MSP430F6721AIPNR supports LPM3 (standby) with RTC, watchdog, and supply supervisor active and full RAM retention. Typical current draw is 1.7 µA at 2.2 V and 2.5 µA at 3.0 V. This value is specified in the "Ultra-Low Power Consumption" subsection of Section 1.1 and applies identically to the MSP430F6721AIPNR as part of the MSP430F672xA family. Wake-up time from LPM3 is 3 µs (typical).

Is the MSP430F6721AIPNR pin-compatible with other devices in the MSP430F672xA family?

Yes, the MSP430F6721AIPNR is pin-compatible with all MSP430F672xA variants in the same package type - specifically, the 80-pin LQFP (PN) footprint shared with MSP430F6720AIPNR, MSP430F6723AIPNR, and MSP430F6724AIPNR. Pin attributes, multiplexing, and power domain assignments are identical, enabling drop-in replacement within the same package. This is verified in Tables 4-2 and 4-4 of the SLASE46A datasheet.