UART TTL to RS485

Hi!

I'm looking for an IC which can convert UART TTL to RS485.

The application would be like this:

BlueTooth with UART TTL (like PAN1720) - signal converter IC - sensor with RS485 interface.

In the past I have tried to do this with BlueGiga devices and with several ICs. I was able to do the conversions from one way only.

If anyone has a reliably solution please share it with me.

Thanks