Powering OBD-II Adapter (UART)

[giulio]

Just got my new Freematics adapter few minutes ago.

As I understand power supply for the adapter (5 Volt) is picked directly from Arduino board, so no problems/questions about it. I would only be sure that the +12V on the OBD connector is completely ignored/unused by the adapter, I'm right?
In other words: if the OBD-connector provides no power at all (namely on the pin 16, if I remember right) there will be no problem for the adapter since that pin is not used at all, I'm right?

note: I ask this 'cause the OBD connector on my motorcycle provides no power at all, you have to provide power by picking it by yourself from the battery. Here below, the OBD adapter that 99,9% of us (i.e. bikers) are using:

obdconnector.jpg (10.82 KiB) Viewed 16007 times

[idaka]

Hello,giulio,
i use the same cable like in your picture to connect the Adapter to my Ducati.
The red cable is +12V to power the Adapter,the Adapter powers the Arduino with 5V.
(I use the I2C Adapter)
This works so far....
But: Connection is not possible to my Bike.I think,it will also not work with your Motoguzzi,
because both Bikes use the same ECU: MagnetiMarelli IAW5AM.
Please post, if you get it working.
Best Regards

[stanley]

The 5V is not picked from Arduino. It's converted and regulated from the 12V. The 5V is for powering Arduino.

[giulio]

Please post, if you get it working.

I will do!

[giulio]

The 5V is not picked from Arduino. It's converted and regulated from the 12V. The 5V is for powering Arduino.

Uh!
So a second question arises: is the adapter somehow protected from voltage spikes coming from the car power?
I read in a lot of post many recommendations in doing so (e.g. via a voltage regulator like LM7085).

[giulio]

Please post, if you get it working.
Best Regards

No way... look at my post here http://freematics.com/forum/viewtopic.php?f=11&t=1527

[stanley]

The 5V is not picked from Arduino. It's converted and regulated from the 12V. The 5V is for powering Arduino.

Uh!
So a second question arises: is the adapter somehow protected from voltage spikes coming from the car power?
I read in a lot of post many recommendations in doing so (e.g. via a voltage regulator like LM7085).

Yes, there is filtering.