Japan Drones RS485 TTL board

Does anyone know what IC this board uses? Is it a MAX485?
Just want to make sure before I purchase that the IC is something high quality from a well known manufacturer, since there are a surprising amount of low-grade knock off ICs on other interface boards.

Hi @jdh42,

The Torqeedo adapter board was a joint effort between my company (JapanDrones) and small Japanese electronics company that I work with a lot called Running Electronics.

The primary intention of the board was really to avoid the mountain of support calls caused by users struggling with DIY boards.

I’ll check with the CEO on what parts went onto the final board.

So the CEO, Shibuya-san, has replied

The RS485 driver IC used in TRQIF01 is MAX3485ED manufactured by TAEJIN TECHNOLOGY CO., LTD.(HTC Korea).https://akizukidenshi.com/catalog/g/g116211/

MAX485 is 5V type and TRQIF01 uses 3.3V power supply,I/O, so it will be MAX3485

We could switch to the Analog Devices/MAXIM for the next batch if people think it would make a difference.

Got it. Out of curiosity, when I’ve worked with RS485 in the past I have used a 120 ohm terminating resistor between A and B channels. On the japandrones board, there are two series resistors in line with A and B. What are the values of these and why were they added? I see R3 looks like the 120 ohm terminating resistor but it is not installed.