Is 5.5volts from external regulator to Vin pin enough??

Projects General Guidance
1

-The voltage regulator is a DC/DC Converter Breakout board (BOB-09370) from www.SparkFun.com
Which utilizes a Lineage Power 12V Pico TLynxTM 6A: Non-Isolated DC-DC Power Module

The output will be 5.5 volts, which will be terminated on the Arduino's Vin and Gnd pins.

According to this spec site, the Vin input should be between 7 to 12 volts:

Will this work? Or is the input too low before going through the internal regulator?

Thanks for your input.

2

It is too low. You will not get 5V powering your arduino. It might still run but it is not a good idea.

3

FutureScience:
The output will be 5.5 volts, which will be terminated on the Arduino's Vin and Gnd pins.

According to this spec site, the Vin input should be between 7 to 12 volts:

Will this work?

I'm pretty sure you already answered your own question....

4

Ideally 7-7.5v

5

There is also the problem that if Vin is lower then spec then the FET that isolates USB +5vdc from the board will not be turned off so you end up with a low Vcc being wired to your PC's USB +5vdc, which can cause problems when you try to upload a sketch or use the serial monitor.

6

Thanks for the replies.

That is going to be a problem, I am using this in my car during cold winters.

I have another option; there is a little USB port for a vehicle that regulates 14.4vdc to 5vdc. I need to check the current draw on the port because it will be on 24/7.

Then I can power the Arduino through the USB cable. That will make interfacing easier, but I will loose being able to plug in with a serial monitor while the vehicle is operating.

.

7

But why are you limited to the converter you mentioned in your opening post?

There are loads of others, like these at Pololu.

8

maybe start over and ask what would be the best way to power an Arduino 24/7 from a vehicle that will be in the cold ?

and define cold. we had a guy on here in the Arctic with -50°C or some krazy cold numbers. if you are only in Nebraska with mild cold like -20°F, that might be easier. ?

what power draw ? is it working or sleeping ? RF monitoring ?

9

The regulators on Pololu look perfect, I can adapt the idea.

So this is in Canada with -30 degree Celsius winters.

The arduino will just power a Chronodot RTC and trigger a relay twice a day. So no much power draw.