getting 3.7v out of 9v battery
#1
05-25-09, 11:21 AM
getting 3.7v out of 9v battery
k im not very good with figuring out what i need to be able to get the voltage out of the 9v battery but i need to have it only put out 3.7 or 5v would work to but the material also need to be few enough to be able to fit in my hand thats the most important part also the material i would be using would be from radio shack they are the only place that sells the stuff but just what be the basics to make this work
thanksBeer 4U2
thanksBeer 4U2
#3
05-25-09, 12:37 PM
well its for a longer battery for an e-cig here is a link of something on the same conceptYouTube - E-Cigarette mod
but i want it run of a 9v but only give out 3.7 or 5v
but i want it run of a 9v but only give out 3.7 or 5v
#4
05-25-09, 01:23 PM
If you know the current draw from the device, you can use a resistor or resistors to limit the voltage. Or, you can use a voltage regulator chip/circuit using a 7805 IC. It's a very simple circuit, providing 5v regulated voltage.
Simple 5V power supply
Simple 5V power supply
#5
05-25-09, 03:45 PM
The amphour rating of a nine volt battery is probably less then that of two AA batteries in series all other battery factors equal. Higher voltage doesn't mean it will last longer.
I assume you are talking about the common 9volt batteries not those that are the size of a two inch cube.
I assume you are talking about the common 9volt batteries not those that are the size of a two inch cube.
