BU9891GUL-W is a serial EEPROM with a serial 3-line interface method. It can operate at a high speed of 2MHz clock (2.5~5.5V), has fast write (write time max. 5ms), single power source operation of 1.7~5.5V, auto address increment function at read operation, write error prevention function, write prohibition at power on, write prohibition by command code, write error prevention function at low voltage, program cycle auto delete and auto end function, READY/BUSY display of program condition and low current consumption
The BU9891GUL-W is a 4‑Kbit serial EEPROM that uses a 3‑line Microwire bus (chip select, serial clock, and serial data I/O). It operates from a single 1.7 V to 5.5 V supply and is offered in a VCSP5OL1 package. The device supports high‑speed operation up to 2 MHz, automatic address increment, and write‑mistake prevention functions.
The note includes absolute maximum ratings, recommended operating conditions, timing diagrams, pin assignments, and command formats. It also lists ordering information and legal notices for use in general‑purpose electronic equipment.
| Capacity | 4 Kbit (256 × 16) |
|---|---|
| Operating Voltage | 1.7 V ~ 5.5 V |
| Maximum Clock Frequency | 2 MHz |
| Write Current (typ.) | 1.2 mA |
| Read Current (typ.) | 0.3 mA |
| Standby Current (typ.) | 0.1 mA |
| Data Retention | 40 years |
| Endurance | 100 000 write cycles |
| Maximum Supply Voltage | -0.3 V ~ +6.5 V |
| Storage Temperature Range | -65 °C ~ +125 °C |
| Operating Temperature Range | -40 °C ~ +85 °C |
The device operates from 1.7 V to 5.5 V.
It can be written up to 100,000 times.
Typical standby current is 0.1 mA.