2 Kbit serial EEPROM with a 3 MHz Microwire bus
The Microchip 93C56C-I/MS is a 2 Kbit serial EEPROM using the Microwire interface, organized as 256 x 8 or 128 x 16 bits. Write-cycle time is 2 ms per word or page. Packaged in an 8-MSOP (3.00 mm width) for surface-mount assembly.
3 MHz vs 2 MHz — the speed edge over the B variant
The 93C56C-I/MS runs at 3 MHz, a full 1 MHz faster than the 93C56B-I/SN (2 MHz). That translates to about 1.5 µs per bit faster readout — meaningful if the host polls this EEPROM for calibration tables or boot parameters at power-up. The C suffix also supports both 8-bit and 16-bit word organization (256 x 8 or 128 x 16), whereas the B variant lists only 128 x 16.
8-MSOP footprint and supply rail
The supply rail is strictly 4.5V to 5.5V; do not pull this part into a 3.3V domain without a level translator on the Microwire lines. Decoupling with a 0.1 µF ceramic close to pin 8 (VCC) is standard.