MLX90109CDC-AAA-000-RE

MLX90109

125kHz RFID Transceiver

3901090109 Page 1 of 16 Data Sheet

Rev 011 Jun/12

Features and Benefits

Unique Parallel Antenna concept for maximum power efficiency.

Power down mode available.

Baud rate selectable “on-chip” filtering for maximum sensitivity.

No zero modulation problems.

 Low cost and compact design

SO8 package and high level of integration for compact reader design.

No external quartz reference required, only 2 resistors plus antenna.

On chip decoding for fast system design and ease of use.

Open drain data and clock outputs for 2-wire serial communication.

Ordering Code

Product Code Temperature Code Package Code Option Code Packing Form Code

MLX90109 E DC AAA-000 RE

MLX90109 E DC AAA-000 TU

MLX90109 C DC AAA-000 RE

MLX90109 C DC AAA-000 TU

Legend:

Temperature Code: E for Temperature Range -40°C to 85°C

C for Temperature Range 0°C to 70°C

MLX90109

125kHz RFID Transceiver

3901090109 Page 2 of 16 Data Sheet

Rev 011 Jun/12

1 Functional diagram

2 Description

The MLX90109 is a single chip RFID transceiver

connected as a parallel resonant circuit, that

determines the carrier frequency and the oscillator

frequency of the reader. This eliminates zero

modulation effects by perfect antenna tuning, and

avoids the need for an external oscillator.

The reader IC can easily be switched to power

down by setting the antenna amplitude to zero.

The MLX90109 can be configured to decode the

transponder signal on-chip. In this case the

decoded signal is available through a 2-wire

MLX90109

125kHz RFID Transceiver

3901090109 Page 3 of 16 Data Sheet

Rev 011 Jun/12

Table of Contents

7.1 Loop Gain Oscillator ....................................................................................................................................................................... 6

7.2 Peak Detector ................................................................................................................................................................................ 6

7.3 Band-Pass Filter ............................................................................................................................................................................. 6

7.4 Digital demodulator ........................................................................................................................................................................ 7

7.5 Antenna voltage definition .............................................................................................................................................................. 7

7.6 Power Down mode ......................................................................................................................................................................... 7

7.7 Write operation ............................................................................................................................................................................... 7

8 System design parameters .................................................................................................................................................................... 8

8.1 Auto start-up condition .................................................................................................................................................................... 8

8.2 Antenna current .............................................................................................................................................................................. 8

8.3 Antenna Impedance ....................................................................................................................................................................... 9

9 Typical configuration: READ ONLY...................................................................................................................................................... 10

9.1 Application diagram ...................................................................................................................................................................... 10

9.2 Absolute minimum schematic ....................................................................................................................................................... 10

12 ESD Precautions ............................................................................................................................................................................... 13

13 FAQ ................................................................................................................................................................................................... 14

13.1 Is it possible to make proportional modulation (depth less than 100%) with the MLX90109? ...................................................... 14

13.2 How should I read data information from a transponder up to 15cm? ......................................................................................... 14

13.3 Is it possible to increase the output power of the MLX90109 transceiver? .................................................................................. 14

13.4 Are there any specific coils available for the MLX90109 transceiver? ......................................................................................... 14

13.5 What are the recommended pull-up values on DATA and CLOCK pins? .................................................................................... 14

14 Package Information .......................................................................................................................................................................... 15

14.1 Plastic SO8 ................................................................................................................................................................................ 15

15 Disclaimer .......................................................................................................................................................................................... 16