4Kbit SPI EEPROM in 8-TSSOP
The M95040-WDW6TP is a 4Kbit serial EEPROM from STMicroelectronics, organized as 512 x 8 bits and accessed via an SPI bus at up to 20 MHz. The 2.5 V to 5.5 V supply range lets it operate from a 3.3 V or 5 V rail without a separate regulator — the same part number covers both voltage domains in a mixed-supply board. The 5 ms page write time means a full 512-byte array can be rewritten in under 2.6 seconds at the byte level, though a page-buffered write cuts that to 5 ms per 16-byte page. For a data-logging application writing 16-byte records every minute, the write cycle time is negligible — the SPI bus speed is the throughput bottleneck, not the memory array.
Industrial temperature and supply flexibility
Rated for -40°C to 85°C ambient, this is the standard industrial temperature grade. The 2.5 V minimum supply ensures the part stays operational through a 3.3 V rail dipped to 2.7 V under load — a common brownout margin in 24 V fieldbus-powered sensor nodes. The 8-TSSOP package (4.40 mm body width) is a space-efficient footprint for dense PCB layouts. The 0.65 mm pin pitch is standard for this package family, so the land pattern matches existing TSSOP-8 EEPROM footprints without a board respin.
Active production and compliance
The part is supplied in Tape & Reel or Cut Tape options, covering both automated pick-and-place assembly and prototype or low-volume builds. The reel quantity supports high-volume manufacturing without a reel-change penalty.