M24LR04E-R datasheet(42/142 Pages) STMICROELECTRONICS

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RF device operation

M24LR04E-R

42/142

Doc ID 022208 Rev 5

RF device operation

The M24LR04E-R is divided into 4 sectors of 32 blocks of 32 bits, as shown in Table 5. Each

sector can be individually read- and/or write-protected using a specific lock or password

command.

Read and Write operations are possible if the addressed block is not protected. During a

Write, the 32 bits of the block are replaced by the new 32-bit value.

The M24LR04E-R also has a 64-bit block that is used to store the 64-bit unique identifier

(UID). The UID is compliant with the ISO 15963 description, and its value is used during the

anticollision sequence (Inventory). This block is not accessible by the user and its value is

written by ST on the production line.

The M24LR04E-R also includes an AFI register in which the application family identifier is

stored, and a DSFID register in which the data storage family identifier used in the

anticollision algorithm is stored.

The M24LR04E-R has three 32-bit blocks in which the password codes are stored and a 8-

bit Configuration byte in which the Energy harvesting mode and RF WIP/BUSY pin

configuration is stored.

7.1

RF communication and energy harvesting

Because current consumption can affect the AC signal delivered by the antenna, RF

communications with M24LR04E-R are not guaranteed during voltage delivery on the

energy harvesting analog output Vout.

RF communication can disturb and possibly stop Energy Harvesting mode.

M24LR04E-R Datasheet(PDF) 42 Page - STMicroelectronics