Bidirectional bus driver / voltage converter 12 / 3.3V

[asrock70]

I have proprietary bus (length 300m) speed about 1kHz voltage level 0/12V towards to GND,bidirectional.
Old bus driver with ESD protection is on picture Input Output is any MCU 3.3V.
´Are there any more integrated solutions with similar durability and price?

 

[FvM]

May be a LIN bus driver?

 

[dick_freebird]

There are quite a few power MOSFET low side drivers which
would be more than capable of smacking the load around at
12V, from TTL compatible inputs. Low enough impedance
that you could source-terminate (if that helps you any).

 

[D.A.(Tony)Stewart]

Is this a FDX or HDX bidirectional link? Is it Async or Sync? Baud rate? 1200?

You ought to make the bus balanced differential and controlled impedance to minimize reflections. This might be 200 to 240 Ohms differential impedance for twisted pair.

You will need a CM choke at each end.

Your impedances are 10 Ohms from the driver, which is too low. That gives a stronger Tx signal but worse SNR at far end and reflections at Tx end.

Due to frequency loss gradient on long haul, baseband NRZ has more ISI than BiPhase which shots the BW up to the clock rate.

You can get much better speed and SNR using a PHY magnetic port adapter, such as used in telephony , Ethernet etc but tuned for your cable. (UTP, CATx or whatever) what do you have?

 

[FvM]

To add a reference for an industry standard LIN transceiver: https://www.ti.com/lit/ds/symlink/sn65hvda100-q1.pdf

 

[asrock70]

Thank you, It really looks like linbus.
Pity that nobody does double lindriver I need one driver for clock and second driver for data line.

 

[D.A.(Tony)Stewart]

I doubt you can achieve great performance at 300m with the LIN driver. It may work in a lab, but not in the presence of EMI.

Single wire communications up to 19.2 kbit/s @ 40 meter bus length.
In the LIN specification 2.2,the speed up to 20 kbit/s.

 

[FvM]

If there's an EMI problem in the application, which may certainly be the case, it will be unlikely caused by the LIN driver.