I am designing a RS-485 Profibus Interface; I intend to use the transceiver ADM2486. On the datasheet, isn´t necessary use pullup and pull down resistors for fail-safe biasing purposes. However, the Profibus Specification recommends to use 100k pullup/pulldown resistors between A terminal and Vcc and B terminal and GND, respectively. In this case, instead of using ADM2486 is using DS75176 (National Semiconductor). Which recommendation of the Analog Devices?
Attached on this message is the circuit recommended by Profibus Specification.