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EIA/TIA -485 Compliance

Category: Datasheet/Specs
Product Number: MAX22502E

Is the MAX22502E EIA-485 compliant?

I understand that preemphasis(when enabled) would likely make the TX side non-compliant. 

  • MAX22502 products are compatible with other 100Mbps RS-485 transceivers and further explanation can be found in this technical note. How Far and How Fast Can You Go With RS-485? | Analog Devices

  • Thank you for the reply, we need to provide proof of EIA-485 compliance to our end customer.

  • Wayne, EIA-485 standard was defined in the 1980's as a physical layer specification and the various manufacturers of RS-485 transceivers show proof of meeting these minimum value spec's in the EC table within the product datasheets. These specs include minimum levels of data rate, cable length, driver voltage levels, input voltage range, input resistance, etc. However, since the inception of this 'standard', multiple manufacturers including Analog Devices have pushed beyond the original specs. For example, originally the target data rate was 10Mbps but the MAX22502 actually meets 100Mbps but maintains the voltage levels needed for physical layer compliance. The best I can say is that you show your end customer the MAX22502 datasheet  MAX22502E - 100Mbps Full-Duplex RS-485/RS-422 Transceiver for Long Cables ( which is the ultimate 'proof' that we meet EIA-485 standard. I hope this helps you explain to your end customer.

  • With PE enabled the transmitter meets the voltage limits within the CMR to connect to a RS485 compatible receiver. The MAX22502 was defined primarily for applications requiring higher speed (100Mbps) and typically point-to-point applications. At the time this chip was introduced it was the first 100Mbps RS485 transceiver, and as such engineers used the MAX22502 at both ends of the cable. The input receiver for the MAX22502 is slightly less than the 12kohm UL specified by the RS485 standard, but since the intended application was primarily for point-to-point rather than 32 ULs this is not a significant issue.