Texas Instruments MSP430AFE231IPW

Overview

MSP430AFE231IPW from Texas Instruments is an ultra-low-power mixed-signal microcontroller featuring a 16-bit RISC CPU, 8 KB flash memory, 512 B RAM, and one 24-bit sigma-delta ADC with differential PGA input. It operates from 1.8 V to 3.6 V, achieves 220 µA active current at 1 MHz/2.2 V, and supports single-phase electricity metering with integrated analog front-end precision.

For engineers reviewing the MSP430AFE231IPW datasheet, MSP430AFE231IPW pinout, MSP430AFE231IPW application, or MSP430AFE231IPW equivalent, this device is selected for metrology-grade energy measurement where low standby power (0.5 µA), fast wake-up (<1 µs), and on-chip SD24_A ADC channel count are critical design constraints.

Technical Context

The MSP430AFE231IPW implements a digitally controlled oscillator (DCO) with two factory-calibrated frequencies up to 12 MHz, paired with internal VLO and external HF crystal support (up to 16 MHz). Its clock system feeds MCLK, SMCLK, and ACLK domains independently to optimize power/performance trade-offs across operating modes.

It integrates a single SD24_A sigma-delta ADC with 24-bit resolution, differential input pairs (A0.0±), programmable gain amplifier, internal reference buffer, and bit-stream output via dedicated pins (SDCLK, SD0DO). The ADC operates within 2.5–3.6 V analog supply range and supports temperature sensing and VCC monitoring functions.

Key Specifications

Pinout & Package

TSSOP-24 (PW) package, 7.8 mm × 4.4 mm body size, with exposed pad not electrically connected. Pin 1 marked by dot; NC pins (3, 4, 8, 9) must be connected to AVSS per TI recommendation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MSP430AFE231IPW, MSP430AFE232IPW adds a second ADC channel without increasing power or footprint, while MSP430AFE221IPW reduces memory to lower unit cost - both maintain identical analog performance and timing behavior for metrology-critical paths.

Availability

MSP430AFE231IPW is available at Aetrix Electronics and suitable for single-phase electricity metering, digital power monitoring, and ultra-low-power sensor interface applications requiring stable component supply and long-term lifecycle assurance.

Supply support for MSP430AFE231IPW 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 over 50 years of leadership in low-power design.

The MSP430AFE2xx product line targets precision metrology applications, integrating sigma-delta ADCs and ultra-low-power MCUs to replace discrete analog front-ends in utility-grade energy measurement systems.

FAQ

What is the maximum system clock frequency supported by the MSP430AFE231IPW?

The MSP430AFE231IPW supports a maximum MCLK frequency of 12 MHz when VCC ≥ 3.3 V and duty cycle is 50% ±10%. At 2.7 V, max frequency is 9 MHz; at 1.8 V, it is 4.15 MHz. These limits ensure stable operation of the DCO and all peripherals including the SD24_A ADC and Timer_A3.

Does the MSP430AFE231IPW include an internal voltage reference for the ADC?

Yes, the MSP430AFE231IPW includes an internal voltage reference that can be output on the VREF pin as a mid-rail (VCC/2) signal. It also supports external 2.5 V references applied to VREF for higher stability. This reference is directly used by the SD24_A ADC and enables ratiometric measurements without external components.

How many analog input channels does the MSP430AFE231IPW support?

The MSP430AFE231IPW supports one 24-bit sigma-delta ADC (SD24_A) with a single differential input pair: A0.0+ and A0.0−. Unlike MSP430AFE2x2/x3 variants, it does not include A1.0± or A2.0± inputs - confirmed by pinout diagrams and Table 4-1 in SLAS701B.

What debug interface does the MSP430AFE231IPW use?

The MSP430AFE231IPW uses the Spy-Bi-Wire (SBW) interface via pins TEST/SBWTCK (Pin 10) and RST/NMI/SBWTDIO (Pin 11). This two-wire protocol replaces full JTAG, enabling in-system programming and debugging with minimal PCB footprint and no external voltage required.

Is the MSP430AFE231IPW qualified for use in electricity metering standards such as IEC 62053?

Yes, the MSP430AFE231IPW is designed for IEC 62053-21 Class 0.5 and 1.0 electricity meters. Its SD24_A ADC provides 24-bit resolution, low drift, and integrated PGA - validated in TI reference designs like TIDM-AMMETER - meeting accuracy, linearity, and temperature stability requirements specified in the standard.