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How to connect Arduino to car electric system (12V) ?

userHead Sly 2013-07-26 02:30:41 12339 Views4 Replies
I don't want to connect it through lighter connector, I want to throw a dedicated wire and make it hidden.

I heard that voltage regulator is needed for this.

Will this work:
[url=http://www.dfrobot.com/index.php?route=product/product&filter_name=voltage%20regulator&product_id=584#.UfD8U6zpzto]http://www.dfrobot.com/index.php?route=product/product&filter_name=voltage%20regulator&product_id=584#.UfD8U6zpzto[/url]

What will happen if car voltage will be lower than 12V?

And if not this , what else do I need to connect arduino to car system?
2013-07-28 08:32:47 sure !
I didn't tell to use a 7809, I was just saying that 9V were not necessary , if you power the arduino using the jack plug (thus through the internal 5V regulator), 7.5V are enough .
There are several solutions :

- 7808 ,  7809 ... easy and cheap, but power wasted in heat
- DC-DC module, output 7<- > 9V  : no external waste or heat, but still waste in the arduino reg.  ... expensive ?
- DC-DC module output 5V direct to Vin : no waste or heat ... more expensive ?
userHeadPic alnath
2013-07-28 04:24:20 [quote="Sly"]

Problem is, I need gprs/gps shield and it has recommended 9V power supply. While almost all power banks supplying usb 5V connection only.  I've found universal power bank that can output 9V, but it costs over $80, which is overkill for me.

Any ideas?
[/quote]

When you power the arduino board using the jack plug, it goes to th input of the internal regulator, which outputs 5V ! Then no need to come with 9V -
Actually, GPS/GPRS shield doesn't need that your power supply is 9V mini... what is important is that it can deliver more than 2A (not for a long time though ;) ) , especially at startup, when the GSM connects to the network, and sometimes, when receiving/emitting calls/SMS .
As the internal regulator needs minimum 2V between its input and the output (5** -> 7Vminimum), they say 9V .... to be sure that, if the power supply voltage drops during bursts , it will still be over 7V  ;)
So don't worry , I've tried with 7809 and 7808 external regulators, connecting the output to the jack plug of arduino, and, as long as my battery pack gives enough, everything works well .

I think that you could use an external 5V (well regulated !!) power supply and connect it to Vin , but....make sure it is a good 5V and not more than 5V
userHeadPic alnath
2013-07-27 14:01:12 Thanks, I think that will do.

But while I was considering connecting options, I thought about power-independent version of my project.
So maybe it could be something like power bank (like this one [url=http://dx.com/p/power-bank-6000mah-mobile-external-power-battery-charger-white-124418]http://dx.com/p/power-bank-6000mah-mobile-external-power-battery-charger-white-124418[/url]) connected to 12V, and Arduino connected to it.

Problem is, I need gprs/gps shield and it has recommended 9V power supply. While almost all power banks supplying usb 5V connection only.  I've found universal power bank that can output 9V, but it costs over $80, which is overkill for me.

Any ideas?
userHeadPic Sly
2013-07-27 06:41:26 Yes, it would work, but, even if it can support it, the 12volts output is a bit too high for your arduino. The internal regulator will get hot, especially if you use the GPS/GPRS shield  ;)
I would use this one [url=https://www.dfrobot.com/index.php?route=product/product&path=70_119&product_id=752#.UfKJTEnnOxU]https://www.dfrobot.com/index.php?route=product/product&path=70_119&product_id=752#.UfKJTEnnOxU[/url]
ok, it is not waterproof, but I guess it doesn't rain in your car  :P  , and you can adjust the output value. Then if you adjust it to be 9 volts, eveything will be OK
userHeadPic alnath