Texas Instruments MSP430F1122IRHBT

Overview

MSP430F1122IRHBT from Texas Instruments is an ultralow-power 16-bit RISC microcontroller featuring 4KB Flash, 256B RAM, a 10-bit 200-ksps ADC with internal reference and autoscan, Timer_A with three capture/compare registers, and serial communication capability via UART/SPI (not implemented in this variant). It operates from 1.8 V to 3.6 V and supports five power-saving modes, enabling use in battery-powered sensor nodes and portable measurement systems.

For engineers reviewing the MSP430F1122IRHBT datasheet, MSP430F1122IRHBT pinout, MSP430F1122IRHBT application, or MSP430F1122IRHBT equivalent, key selection criteria include its 20-pin QFN (RHB) package, absence of integrated USART0 (distinguishing it from MSP430x12x2), wake-up time under 6 µs from standby, and support for crystal, resistor, or external clock sources in the basic clock module.

Technical Context

The MSP430F1122IRHBT implements a 16-bit RISC CPU with 125 ns instruction cycle time and seven addressing modes. Its architecture includes constant generators and 16 general-purpose registers, enabling high code efficiency for embedded signal processing tasks such as glass breakage detection using wave digital filters.

It integrates a digitally controlled oscillator (DCO) that stabilizes in less than 6 µs, supporting fast wake-up from LPM3/LPM4. The device uses a modular peripheral set including ADC10 with data transfer controller (DTC), Timer_A3 with three CC registers, and JTAG-based debug/test interface - all operating within the 1.8–3.6 V supply range and −40°C to 85°C temperature grade.

Key Specifications

Pinout & Package

Package: 32-pin QFN (RHB), 5 mm × 5 mm, exposed thermal pad (recommended connection to VSS).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultralow-power mixed-signal microcontroller applications.

Compared with MSP430F1122IRHBT, the MSP430F1132IRHBT offers double Flash capacity with no trade-offs in power or peripheral set, while the MSP430F1222IRHBT adds communication capability at the cost of slightly higher active current and altered peripheral enable register layout.

Availability

MSP430F1122IRHBT is available at Aetrix Electronics and suitable for smart utility metering, portable gas detection, wireless sensor nodes, industrial temperature monitoring, and battery-backed data loggers requiring stable component supply across extended product lifecycles.

Supply support for MSP430F1122IRHBT 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 specializing in analog, embedded processing, and connectivity technologies with over 50 years of innovation in low-power design.

The MSP430x11x2 product line was engineered for ultralow-power portable measurement and sensing applications, emphasizing rapid wake-up, integrated analog peripherals, and long-term battery operation in harsh environments.

FAQ

What is the maximum ADC sampling rate supported by the MSP430F1122IRHBT?

The MSP430F1122IRHBT features a 10-bit successive approximation register (SAR) ADC capable of 200 ksamples per second (ksps) under optimal conditions - specifically with internal reference enabled, sample-and-hold active, and autoscan disabled. At full resolution, sustained throughput is typically 100–150 ksps depending on clock configuration and conversion mode. The MSP430F1122IRHBT's ADC10 module includes a data transfer controller (DTC) that automates result storage without CPU intervention, preserving low-power operation during high-speed acquisition sequences.

Does the MSP430F1122IRHBT include a hardware UART or USART peripheral?

No, the MSP430F1122IRHBT does not include a hardware UART or USART peripheral. That functionality is exclusive to the MSP430x12x2 family (e.g., MSP430F1222IRHBT). The MSP430F1122IRHBT supports only software-based UART emulation via Timer_A outputs and GPIO interrupts. Its pinout and peripheral file map confirm absence of U0TXBUF, U0RXBUF, or USART control registers - making it unsuitable for applications requiring hardware-assisted serial communication without external bridging components.

What is the purpose of the ROSC pin on the MSP430F1122IRHBT?

The ROSC pin (P2.5) on the MSP430F1122IRHBT serves as the input for an external resistor that sets the nominal frequency of the digitally controlled oscillator (DCO). This resistor determines the DCO's base speed before calibration, enabling fast wake-up (<6 µs) from low-power modes without relying on crystal startup delay. When not used for DCO tuning, P2.5 functions as a general-purpose I/O pin. The MSP430F1122IRHBT's datasheet specifies typical resistor values between 2.2 kΩ and 50 kΩ depending on target frequency and temperature stability requirements.

Can the MSP430F1122IRHBT operate from a 1.8 V supply without performance degradation?

Yes, the MSP430F1122IRHBT is fully specified to operate across 1.8 V to 3.6 V, with all peripherals - including the 10-bit ADC, Timer_A, Flash memory, and JTAG interface - functional at the minimum 1.8 V supply. At 1.8 V, the maximum CPU frequency is reduced to approximately 1 MHz (vs. ~8 MHz at 3.3 V), but the 125 ns instruction cycle time remains guaranteed per datasheet timing characteristics. The MSP430F1122IRHBT's brownout protection circuit ensures safe reset behavior down to 1.7 V, preserving data integrity during battery discharge.

How many I/O pins does the MSP430F1122IRHBT provide in the RHB package?

The MSP430F1122IRHBT in the 32-pin QFN (RHB) package provides 14 dedicated I/O pins: eight on Port P1 (P1.0–P1.7), six on Port P2 (P2.0–P2.5), and no Port P3 (which is exclusive to MSP430x12x2 devices). Pins marked NC (e.g., RHB pins 4, 17, 20, 31) are not internally connected and must be tied to VSS. Reserved pins (RHB pins 9–16) are also unassigned and require VSS connection to avoid floating nodes and increased current consumption. All 14 I/Os support interrupt-on-change capability.