How to connect the WP (Write Protect) pin of an EEPROM?

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Usually, you should connect the WP pin to GND. This disables write protection, i.e. you can read and write to the EEPROM.

The WP pin is active-high, i.e. pulling it to VCC enables the write protection. For details, refer to your EEPROM’s datasheet, e.g. the AT24CS04 dataheet. The function of the write protect pin is idential in all 24xx series EEPROMs, even across manufacturers.

In case you want to enable write protection to avoid accidentally overwriting your data, you should connect the WP pin to a microcontroller or an external logic circuitry. Connecting it to a microcontroller is typically the easiest option.

The following picture shows an EEPROM connected correctly in KiCAD so that read and write is enabled.