can I get -5v from arduino?

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi
Is there a way to get -5v using power from arduino?

2

N0, not without some external components.

Lefty

3

thank you for your reply

can you suggest any such component?

4

It depends on how much current you need.

5

Well if this is the only connection you need to the arduino, you can use 5v as ground and ground as -5V. But then you need to ensure that there is no other connection, and that the ground planes are indeed separate.

Joachim

6

If all you need is a few milliamps then the easiest is:
http://www.national.com/mpf/LM/LMC7660.html

I'm using this to get a -3.3 from a 3.3V Arduino design to allow me to drive an LCD. One of the problems with 3.3 is driving LCDs. They need more that 3.3V swing on the contrast. The 7660 is just what is needed for that.

It's a cheapie switching regulator, so you probably wouldn't want to use it for some op-amp like power source. Too much noise.

7

thank you for your replies
I want to use it to drive an opamp that is needed for a flexiforce sensor...

8

Try and look for voltage mirrors, this is a typical one:-