For a project, I need to connect more than one device to an Arduino through a serial port with hardware flow control (RTS/CTS).

Sparkfun used to make breakout boards for the SC16IS750, but this product is discontinued and I can't find any place to order it. There are also plenty of ICs doing what I need, but I am not keen on soldering SMD components and I cannot find any products coming in e.g. an old fashioned DIP package.

Does someone know about an available breakout board or a DIP packages I2C to UART bridge? Since the device will be battery powered, I would prefer a dedicated low-power circuit instead of a programmed microcontroller as suggested by majenko.

  • How about an ATMega328P programmed to do what you want...?
    – Majenko
    Commented Nov 10, 2016 at 18:50
  • @Majenko Why didn't I think about that. It would actually work, but since I need the bridge to be always on in a battery-powered device, the power consumption of the ATMega328P is at least disadvantageous. I would prefer a dedicated circuit. I'll edit my question and add the power requirement.
    – jarnbjo
    Commented Nov 10, 2016 at 19:53
  • An ATTiny would reduce the power a little - so would employing sleep modes and wake on I2C or UART interrupts.
    – Majenko
    Commented Nov 10, 2016 at 20:34
  • Yes, sleep modes should do it. Note that hardware flow control is not incompatible with software serial in concept, though there might be a few details to work out. There may also be dual-UART ATmegas available in large DIP packages. Commented Nov 10, 2016 at 23:22
  • You really should invest an hour or two in learning to solder SMD device though - it is not hard at all, and will remove these extreme limitations you face. Commented Nov 10, 2016 at 23:31

1 Answer 1


Perhaps what you're looking for:


From that page:

SC16IS750 I2C/SPI to UART Bridge Module

SC16IS750 I2C/SPI to UART Bridge Module

This module is designed to enable I2C/SPI to UART conversion. It works in I2C/SPI slave mode and interfaces with devices working in I2C/SPI master mode. There are also 4 extra GPIOs for IO expansion. NXP SC16IS750 is used as the key component on this module. Flow control and modem signals are also supported.

This module is useful when extra UART interface is needed. Due to the multi-slave characteristics of I2C and SPI, many UART interfaces could be added to the system at the same time.

  • @MichaelWilkinson Please consider posting a little summary, because your post will be worthless when the source you are linking to changes or is deleted.
    – Ariser
    Commented Feb 8, 2017 at 15:04
  • Agreed - links go dead in time. Please summarise your answer so that it stands on its own. At least mention the part number, and maybe post a photo of it.
    – Nick Gammon
    Commented Feb 10, 2017 at 5:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.