Automotive-grade 1Kbit EEPROM for calibration and configuration storage
The ROHM BR93A46RFVT-WME2 is a 1Kbit serial EEPROM organized as 64 words by 16 bits, communicating over a Microwire interface at up to 2 MHz. It is qualified to AEC-Q100, making it suitable for automotive under-hood and chassis-domain applications where non-volatile storage of calibration constants, VIN data, or trim values is needed.
2 MHz Microwire — bus timing for mixed-voltage ECUs
The 2 MHz clock frequency on the Microwire interface gives a 500 ns minimum clock period. In a typical automotive ECU with a 10 MHz SPI master, this EEPROM is the speed-limiting device on the bus. The 5 ms write cycle time (word or page) means the host must wait that long after a write command before initiating the next operation — a firmware timer or status-polling routine is needed, not a blind back-to-back write. For a 64-word configuration block, a full rewrite takes about 320 ms at the write-cycle limit.
Package and footprint for production reflow
Housed in an 8-TSSOP-B (0.173", 4.40 mm width) surface-mount package, this part is hand-solderable with a fine-tip iron or hot-air station — the 0.65 mm pitch is manageable for a maker prototype, though production lines will use reflow.