Author Topic: what is the voltage range on vin? (Read 9029 times)

Anthony · « **on:** January 18, 2013, 04:24:51 pm »

Hi

I need to connect my digispark to a 9v battery. I know I saw the input range for vin somewhere, but I can't find it. Can someone help me out.

As a secondary question, does the serial connection run through the voltage regulator, or is that expected to only be 5v? I thought a quick solution to a problem would be to rig a usb cable end to a battery, but that would only work if that was regulated also. My guess is it's not, but I though I would ask.

Thanks

JeffRand · « **Reply #1 on:** January 18, 2013, 05:45:33 pm »

A 9v battery should work fine. The regulator should work anywhere from about 7v to 35v.

I\'m not sure what you\'re asking in the second question. The regulator will reduce the voltage to the digispark to 5v. That is what you will see on most of the port pins.

Anthony · « **Reply #2 on:** January 18, 2013, 06:46:10 pm »

I thought it was 7 to 35, but I could not find it. I wanted to be sure before I did it.

I may not have been clear about the second questions, and to be honest I\'m not sure how to ask it. It\'s clear in my head but I can\'t get it out. Let me try again.

My understand is that the USB port is 5v on the power line of the cable, is that true? If that is correct what would happen to a digispark if I rewired a usb cable and supplied 9v on the power line of the power cable?

I know it sounds kind of dumb, but if I could do that I could move away from the computer without soldering on a battery connector. I think it would be really useful for temporary projects.

JeffRand · « **Reply #3 on:** January 18, 2013, 06:56:12 pm »

Applying 9v to the USB connector would likely fry the digispark. When you supply voltage via the USB, the 5v regulator isn\'t being used.

digistump · « **Reply #4 on:** January 18, 2013, 07:25:10 pm »

USB connector and 5v pin should only have 4.5 to 5.5v applied to them at any time.

The VIN pin can take 7-35v - though at 35v it would overheat the regulator very quickly - so 7- about 15v is a more practical range. It can output up to 500ma.

Anthony · « **Reply #5 on:** January 18, 2013, 09:20:49 pm »

That\'s what I thought about the usb, but I figured it could not hurt to ask.

I did solder the battery connector to vin and ground and it worked great.

Anthony · « **Reply #6 on:** January 18, 2013, 09:21:21 pm »

Thanks for the responses.