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Bosse
- 22nd April 2010, 07:10
Hi, have a problem to drive 1-Wire lines over 35 meter. Can anyone help me to find a solution for stronger signals. Have mounted a pullup resistor 550 Ohms and are afraid that this is to small, but it works. Need a form for amplifier???

Bosse

Ioannis
- 22nd April 2010, 09:49
If it works where is the problem?

Maxim has a few articles on such cases with mosfet drivers etc. But I don't think you need them.

Ioannis

Bosse
- 22nd April 2010, 10:42
If it works where is the problem?

Maxim has a few articles on such cases with mosfet drivers etc. But I don't think you need them.

Ioannis

I'm afraid that the Pullup is to small???

Ioannis
- 22nd April 2010, 11:29
The port can sink 20-25mA. At 5volts/550 that is 9,09mA. So you are absolutely safe.

But even if you short the output (Not recommended though) nothing will happen as the outputs are fets that limit the current as he temp rises.

Ioannis

Bosse
- 22nd April 2010, 13:09
The port can sink 20-25mA. At 5volts/550 that is 9,09mA. So you are absolutely safe.

But even if you short the output (Not recommended though) nothing will happen as the outputs are fets that limit the current as he temp rises.

Ioannis

Thank you very much Ioannis