SparkFun (PID 10124) Transceiver Breakout - RS-485

♪ [ZZ Top] ♪ ♪ Been waitin' for the bus all day ♪ Hi, I'm Chris Olson with NVE Corporation. Today we're demonstrating the world's fastest isolated RS-485 transceivers. We're using two of our IL3585 evaluation boards, which you can buy on our Website. Here's the circuit. The boards have a 120 ohm termination resistor on each end. The boards are connected with 10 meters of twisted-pair shielded cable. The yellow trace is the input; green is the output. The propagation delay is only 96 nanoseconds for two transceivers, and about 33 nanoseconds of that is the speed of light through the 10 meter cable. Now we'll test the fastest competitive parts. The propagation delay is 140 nanoseconds, or about 45 nanoseconds slower than with our parts. Here are the IL3585 switching specifications: Typical propagation delay is 30 nanoseconds, and we had less than that in our test. Pulse skew is typically