AT24C21-10PC-2.5 AT24C21-10PI-2.5 AT24C21-10SC-2.5 AT24C21-10SC-2.7 AT24C21-10SI-2.5 AT24C21-10SI-2.7 AT24C21-10SU-2.5 AT24C21-25PC AT24C21AN-10SU-2.7 AT24C21AN-10SU2.7/2.5