Hi, I have a filter circuit that uses opamps, the problem is that opamps require -5V, my circuit is suppose to be part of a portable system, so I'll need to use a battery. I've used a charge pump to helo get me a -5V supply, but instead of giving me -Vin which would be equal to -5V it's giving me only -2V, which is too little. Anyone have an idea on how to get a proper -5V supply.
You can get ICs, whose work not correctly. Maybe it is your problem. At me, the maxim ICs don't work usually. I have used a tps60400 to get -5V in a project with OPAMP, and it worked well.