Download the E28F400BV datasheet PDF.
This datasheet also includes the E28F004BV variant, as both parts are published together in a single manufacturer document.
E PRELIMINARY
4-MBIT (256K X 16, 512K X 8) SmartVoltage BOOT BLOCK FLASH
MEMORY FAMILY 28F400BV-T/B, 28F400CV-T/B, 28F004BV-T/B 28F400CE-T/B, 28F004BE-T/B n Intel SmartVoltage Technology
5V or 12V.