AMIS-49200 Datasheet, PDF(2/22 Page) AMI SEMICONDUCTOR

1.0 Introduction........................................................................................................................................................................................... 3

1.1 Overview........................................................................................................................................................................................... 3

1.2 Definitions, Acronyms and Abbreviations.......................................................................................................................................... 3

1.3 References ....................................................................................................................................................................................... 3

2.0 AMIS-49200 Fieldbus MAU Description ............................................................................................................................................... 3

2.1 Features............................................................................................................................................................................................ 3

2.2 Block Diagram .................................................................................................................................................................................. 4

2.3 Package Information ......................................................................................................................................................................... 5

3.0 Electrical Characteristics ...................................................................................................................................................................... 8

3.1 Operating Conditions ........................................................................................................................................................................ 8

3.2 Power Supply Blocks ........................................................................................................................................................................ 9

3.3 Transmitter Blocks ............................................................................................................................................................................ 9

3.4 Receiver Block ................................................................................................................................................................................ 11

4.0 Theory of Operation ........................................................................................................................................................................... 12

4.1 Overview......................................................................................................................................................................................... 12

4.2 Power Supply Block ........................................................................................................................................................................ 12

4.2.1. Shunt Regulator ...................................................................................................................................................................... 12

4.2.2. Series Regulator...................................................................................................................................................................... 13

4.2.3. Low Voltage Detectors ............................................................................................................................................................ 13

4.2.4. Voltage Reference................................................................................................................................................................... 14

4.3 Transmit Block ................................................................................................................................................................................ 15

4.3.1. MDS-interface ......................................................................................................................................................................... 15

4.3.2. Tri-level Modulator................................................................................................................................................................... 15

4.3.3. Slew Rate Controller ............................................................................................................................................................... 16

4.3.4. Current Drive Amplifier ............................................................................................................................................................ 16

4.4 Receive Block ................................................................................................................................................................................. 16

4.4.1. Band Pass Filter ...................................................................................................................................................................... 17

4.4.2. Receive Signal Detection ........................................................................................................................................................ 17

5.0 AMIS-49200 as Replacement for Yokogawa ÂµSAA22Q..................................................................................................................... 18

5.1 Functional Differences Between the ÂµSAA22Q and the AMIS-49200............................................................................................. 18

5.1.1. Jabber Inhibit........................................................................................................................................................................... 18

5.1.2. Low Power Mode..................................................................................................................................................................... 18

5.2 Pin Differences Between the ÂµSAA22Q and the AMIS-49200 ........................................................................................................ 19

5.3 External Circuitry............................................................................................................................................................................. 20

5.4 Active Components......................................................................................................................................................................... 21

5.5 Alternative Designs ......................................................................................................................................................................... 21

5.6 Verification ...................................................................................................................................................................................... 21

6.0 Appendix (A) â Manchester Encoding ................................................................................................................................................ 22

7.0 Company or Product Inquiries ............................................................................................................................................................ 22

AMI Semiconductor â Jan. 07, M-20532-003