20MHz 16-bit core with 256KB Flash — what fits in the BGA footprint
The MSP430F5638IZQWT is a Texas Instruments MSP430F5xx 16-bit MCU built around the MSP430 CPUXV2 core running at 20MHz. It packs 256KB of Flash and 18KB of RAM — enough for a USB stack plus a modest application layer without external memory. The 113-VFBGA package (BGA Microstar Junior, 7x7 mm) means the board layout must handle a 0.50 mm or finer ball pitch — this is not a hand-solderable part. The 74 I/O lines give enough headroom for a parallel LCD, external memory bus, and sensor array without multiplexing.
Obsolete — what that means for a BOM line
Texas Instruments has marked the MSP430F5638IZQWT as Obsolete. For existing designs already in production, the remaining supply moves through independent distribution — quantities are lot-specific and confirmed at RFQ. If you are sourcing this for a repair or a last-time-buy fill, the 113-BGA Microstar Junior footprint is the constraint. A pin-compatible drop-in from the same MSP430F5xx family would need to share the same ball map — something to verify against the TI package drawing before committing a replacement.
Peripheral set and connectivity — USB, ADC, and the analog chain
On-chip USB 2.0 (full-speed) with the PHY integrated — no external USB transceiver needed. The connectivity block also includes I²C, SPI, UART/USART, LINbus, and IrDA, which covers most industrial sensor bus and debug interfaces. The data converter section provides 16-channel 12-bit ADC and 2-channel 12-bit DAC. For a mixed-signal application like a portable data logger or a sensor hub, the ADC can sample all 16 channels without an external mux, and the DAC outputs can drive analog set-points or alarm thresholds directly. Built-in brown-out detect, POR, DMA, and PWM peripherals reduce external supervisor and timer IC count.
Temperature grade and supply range
This covers most factory-floor and outdoor enclosure environments without active cooling.