Texas Instruments MSP430FR69791IPNR

Overview

MSP430FR69791IPNR from Texas Instruments is a 16-bit ultra-low-power FRAM microcontroller featuring 128KB nonvolatile FRAM, 2KB RAM, 12-bit ADC with 16 external inputs, integrated LCD driver supporting up to 320 segments, and dual eUSCI modules (UART/IrDA/SPI + I²C/SPI). It operates from 1.8 V to 3.6 V and targets battery-powered metering applications requiring RTC, security, and capacitive touch.

For engineers reviewing the MSP430FR69791IPNR datasheet, MSP430FR69791IPNR pinout, MSP430FR69791IPNR application, or MSP430FR69791IPNR equivalent, key selection criteria include FRAM endurance (10¹⁵ write cycles), LPM3.5 RTC current (0.35 µA), AES256 encryption coprocessor, 80-pin LQFP package, and I²C bootloader support.

Technical Context

The MSP430FR69791IPNR implements the MSP430 CPUXV2 core with 16 general-purpose registers and executes instructions in single-cycle mode at up to 16 MHz. Its clock system integrates DCO (10 factory-trimmed frequencies), LFXT (32-kHz crystal), and HFXIN/HFXOUT pins enabled for high-frequency crystal operation - distinguishing it from MSP430FR692x variants where HFXT is omitted.

Peripherals include three 16-bit Timer_A modules (TA0/TA1/TA3), one 16-bit Timer_B (TB0) with seven capture/compare registers, 32-bit hardware multiplier, three-channel DMA, and dual eUSCI_A (UART/IrDA/SPI) and eUSCI_B (I²C/SPI) interfaces. The device supports UART and I²C bootloaders, with I²C BSL active on P1.6 (BSLSDA) and P1.7 (BSLSCL).

Key Specifications

Pinout & Package

The MSP430FR69791IPNR is housed in an 80-pin LQFP (PN) package measuring 12 mm × 12 mm with exposed thermal pad (not electrically connected). Pin functions are multiplexed across digital I/O, analog, timer, communication, and LCD segments - requiring careful signal assignment during PCB layout.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power FRAM microcontroller applications.

Compared with MSP430FR6979IPN, the MSP430FR69791IPNR offers I²C BSL for simplified two-wire field updates; versus MSP430FR6977IPN, it doubles FRAM capacity for extended data retention without compromising power or feature set.

Availability

MSP430FR69791IPNR is available at Aetrix Electronics and suitable for water metering, heat cost allocation, and portable medical logging requiring stable component supply across multi-year production cycles.

Supply support for MSP430FR69791IPNR 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 leader delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and consumer markets.

The MSP430FR69xx family targets ultra-low-power metering and sensing applications, integrating FRAM, LCD drivers, RTC, and cryptographic acceleration to replace legacy flash-based MCUs in battery-operated endpoints.

FAQ

What is the primary memory technology used in the MSP430FR69791IPNR?

The MSP430FR69791IPNR uses ferroelectric RAM (FRAM) for its main nonvolatile memory - 128KB of unified, byte-addressable FRAM that combines the speed of SRAM with the nonvolatility of flash. This enables instant writes without erase cycles, 10¹⁵ write endurance, and operation down to 1.8 V. Unlike flash, FRAM in the MSP430FR69791IPNR allows simultaneous code execution and data logging, making it ideal for long-life metering applications.

Does the MSP430FR69791IPNR support hardware-accelerated cryptography?

Yes, the MSP430FR69791IPNR includes a dedicated AES256 security coprocessor supporting both 128-bit and 256-bit key lengths. It performs encryption and decryption operations independently of the CPU, reducing latency and power consumption during secure firmware updates or encrypted data logging. The coprocessor interfaces directly with FRAM and DMA, enabling end-to-end protected data paths without software overhead - a critical capability for utility meter certification standards.

What LCD configuration does the MSP430FR69791IPNR support?

The MSP430FR69791IPNR integrates the LCD_C peripheral supporting static, 2-, 3-, 4-, 6-, and 8-mux configurations with up to 320 total segments. It drives common outputs (COM0–COM7) and segment lines across multiple ports (P1–P10, PJ), with programmable contrast control and internal charge pump. This eliminates the need for external LCD controllers in applications like smart meters and portable medical devices, reducing system cost and complexity while maintaining low active and standby power.

How does the MSP430FR69791IPNR achieve ultra-low-power RTC operation?

The MSP430FR69791IPNR achieves 0.35 µA typical RTC current in LPM3.5 mode by combining a dedicated low-leakage RTC_C module, internal 32-kHz oscillator circuitry, and optimized power gating. It uses PJ.4/LFXIN and PJ.5/LFXOUT to connect a 3.7-pF 32.768-kHz crystal, with built-in load capacitance eliminating external capacitors. Calendar and alarm functions operate autonomously, waking the CPU only on event triggers - enabling decade-long battery life in utility meter applications without external RTC ICs.

What bootloader interface is implemented on the MSP430FR69791IPNR?

The MSP430FR69791IPNR implements an I²C-based hardware bootloader (BSL) activated on pins P1.6 (BSLSDA) and P1.7 (BSLSCL). This factory-programmed ROM BSL enables in-system firmware updates using only two wires and standard I²C protocol, without requiring JTAG or UART interfaces. It supports secure authentication and memory verification, making it suitable for field upgrades in deployed metering devices where physical access is limited and reliability is critical.