The ROHM BR25H640FVM-2ACTR is a 64Kbit serial EEPROM organized as 8K x 8 bits, accessed over an SPI bus at up to 10 MHz. It's part of ROHM's Automotive, AEC-Q100 series, which means it's qualified for the temperature and reliability demands of under-hood and chassis-domain electronics. Write-cycle time is 4 ms per word or page, which is typical for this density class and fast enough for parameter logging at the 10 MHz bus rate.
125°C operating ceiling — what it buys you
A 125°C junction rating means the part can live in an engine control unit, a transmission controller, or a sensor module bolted to a hot manifold. If your BOM calls for an AEC-Q100-qualified non-volatile memory that holds calibration data through a thermal cycling test, this is the tier you're looking for.
Package and footprint reality
It comes in an 8-MSOP package (the 8-VSSOP / 8-MSOP 2.80 mm width variant) — surface-mount only, no through-hole option. The supplier device package is 8-MSOP, which is a fine-pitch SOP with about 0.65 mm lead pitch. That footprint is shared across several ROHM serial EEPROM densities, so a board layout for a 32Kbit part can often take this 64Kbit drop-in if the pinout matches. The shipping form is Tape & Reel or Cut Tape, so it feeds straight into a pick-and-place line.
Lifecycle — no LTB scramble here
For a procurement decision, that means you can qualify this into a production BOM without budgeting for an obsolescence-driven respin in the next few years. If the line ever does move to phase-out, ROHM typically issues a PCN with a multi-quarter LTB window, but right now there's nothing to watch for.