December 2012

Doc ID 15629 Rev 6

1/25

AN2972

Application note

Designing an antenna for the M24LRxx-R and M24LRxxE-R

dual interface I²C/RFID devices

Introduction

The M24LRxx-R or M24LRxxE-R device is an EEPROM designed for access via two

interface.

Figure 1.

Dual interface EEPROM

Both interfaces are widely used industry standards. The M24LRxx-R or M24LRxxE-R can

be integrated into almost any electronic application, provided that the processor offers an

interface.

The purpose of this application note is also to:

●

explain the basic principle of passive RFID

●

describe the basics of a 13.56 MHz inductive antenna design

●

provide some guidelines for a successful integration, from design to production.

Table 1 lists the products concerned by this application note.

Note:

The standard M24LRxx-R and energy-harvesting M24LRxxE-R devices will be referred to

as M24LRxx devices throughout the document.

Table 1.

Applicable products

Type

Applicable products

Dual interface EEPROMs

M24LRxx-R, M24LRxxE-R

Evaluation boards

ANTx-M24LRxxx, M24LR-Discovery, ROBOT-M24LR16E-A

STEVAL-IHP004V1, STEVAL-IPR002V1, STEVAL-IPE020V1

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