Texas Instruments MSP430FG438IZCAR

Overview

MSP430FG438IZCAR from Texas Instruments is an ultra-low-power 16-bit RISC microcontroller featuring 48 KB Flash, 2 KB RAM, a 12-bit ADC with 12 channels and internal reference, dual 12-bit DACs, three configurable operational amplifiers, two 16-bit timers (Timer_A3 and Timer_B3), integrated LCD driver for up to 128 segments, and USART supporting UART/SPI modes - designed for battery-powered analog sensor systems and digital metering applications.

For engineers reviewing the MSP430FG438IZCAR datasheet, MSP430FG438IZCAR pinout, MSP430FG438IZCAR application, or MSP430FG438IZCAR equivalent, key selection criteria include its 1.8–3.6 V supply range, sub-1 µA LPM4 current, 48 I/O capability, BGA-113 package, and integrated analog front-end with programmable op-amps and DACs for sensor signal conditioning and display control.

Technical Context

The MSP430FG438IZCAR implements a digitally controlled oscillator (DCO) enabling wake-up from LPM3 in under 6 µs, paired with five low-power modes optimized for extended battery life in portable measurement devices. Its architecture integrates single-channel DMA, a 16-bit CPU with constant generators, and dedicated peripherals including Comparator_A and supply-voltage supervisor with programmable trip levels.

It supports dual crystal oscillators (XT1 for LF/32.768 kHz watch crystal or XT2 for up to 8 MHz), flexible clock routing (MCLK, SMCLK, ACLK), and on-chip LCD bias generation with four voltage levels (V1–V5) for segment driving. The device uses separate analog (AVCC/AVSS) and digital (DVCC/DVSS) power domains with strict sequencing requirements (AVCC must not power up before DVCC).

Key Specifications

Pinout & Package

Package: 113-ball BGA (ZCA), 7 mm × 7 mm body size, 0.5 mm pitch, RoHS-compliant. Pinout validated per TI SLAS380F Rev. F (March 2022), Figure 7-2 and Section 7.2.1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MSP430FG439IZCAR and MSP430FG4619IZCAR, the MSP430FG438IZCAR provides optimal balance of analog integration, ultra-low-power operation, and cost for mid-complexity metering and sensor applications - offering identical peripheral functionality to the FG439 but with 12 KB less Flash, and lacking the FG4619's higher-speed ADC and expanded LCD capacity.

Availability

MSP430FG438IZCAR is available at Aetrix Electronics and suitable for hand-held meters, analog sensor systems, digital thermostats, and portable industrial monitors requiring stable component supply, long-term lifecycle support, and RoHS-compliant BGA packaging.

Supply support for MSP430FG438IZCAR 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 MSP430FG43x product line targets ultra-low-power mixed-signal applications demanding integrated analog peripherals, LCD driving, and extended battery life - specifically engineered for portable instrumentation and energy-conscious embedded systems.

FAQ

What is the maximum system clock frequency supported by the MSP430FG438IZCAR?

The MSP430FG438IZCAR supports a maximum system clock (MCLK) frequency of 8 MHz at VCC = 3.6 V, and 4.15 MHz at VCC = 1.8 V, as specified in Section 8.3 Recommended Operating Conditions. This frequency is derived from the DCO or external XT2 oscillator and governs CPU execution speed, timer resolution, and ADC sampling rate limits. The MSP430FG438IZCAR does not support frequencies beyond these values under rated conditions.

Does the MSP430FG438IZCAR support hardware UART communication?

Yes, the MSP430FG438IZCAR supports hardware UART communication via its USART0 module, configurable in asynchronous UART mode using P2.4 (UTXD0) and P2.5 (URXD0) pins. The module includes programmable baud-rate generation, parity, stop bits, and framing error detection - all implemented in hardware without CPU intervention during data transfer. This capability is confirmed in the Functional Block Diagram and Section 7.2.1 Signal Descriptions of the MSP430FG438IZCAR datasheet.

How many analog input channels does the 12-bit ADC in the MSP430FG438IZCAR support?

The 12-bit ADC (ADC12) in the MSP430FG438IZCAR supports 12 analog input channels, as documented in the Device Comparison table (Section 6) and Section 8.22. These channels map to pins P6.0–P6.7, P5.0–P5.1, and P4.0–P4.7 - covering A0 through A15, though only 12 are enabled for the MSP430FG438IZCAR variant. Channel selection is software-controlled via ADC12CTL0 and ADC12MCTLx registers.

Can the MSP430FG438IZCAR drive a 128-segment LCD directly without external bias circuitry?

Yes, the MSP430FG438IZCAR can drive a 128-segment LCD directly using its integrated LCD controller, but external resistive biasing is required. The device provides COM0–COM3 outputs and R03–R33 inputs to connect a 4-resistor ladder generating V1–V5 voltages; it does not include internal charge pumps or voltage doublers. Full 128-segment operation requires proper external bias network design per Section 8.13 and Figure 8-12 in the MSP430FG438IZCAR datasheet.

What power-saving modes are available on the MSP430FG438IZCAR, and what is the lowest current draw?

The MSP430FG438IZCAR offers five low-power modes (LPM0–LPM4). The lowest active-retention current is 0.1 µA in LPM4 (RAM retention only) at 2.2 V and 25°C, as specified in Section 8.4. LPM3 draws 1.1 µA under the same conditions when Basic Timer1 and LCD are active. All modes leverage the DCO and clock gating to minimize dynamic and leakage current, enabling multi-year operation on coin cells in applications like thermostats and remote sensors.