supply-splitting: TLE2426 alternatives?

[Dominique]

Hello!

I want a dual supply from a single battery. In my previous circuit, I was very happy with the TLE2426 from TI, but now I'm searching a solution in SMT, which wil require few space.
Are there other (good) single chip solutions which can be used to power an op-amps?
The circuit to power is a stereo mic preamp and draws 6mA or less, with a voltage between +-1.5V and +-4.5V.
...

 

[Dominique]

... If not, I think about using a simple circuit like the following, just with an op-amp with less current consumption. If possibly someone had hints on improving the circuit I'd be thankful too!

Thanks for reading!
Cheers
Dominique

PS. circuits are taken from http://tangentsoft.net/audio/

 

[AudioWizard]

What is R1 for? Stability?

There are probably solutions available from Maxim (they make some very tiny packages...)

But otherwise, the TLE2426 is available in SOIC package!

Go see there:

http://focus.ti.com/docs/prod/folders/print/tle2426.html

 

[Dominique]

oups! That's good news!

I was so sure it only existed in DIP and TO!
Probably I forgot about SOIC because when I checked the datasheet, I saw a 14pin SOIC package and didn't understand why - but in fact the package is SOIC8 and the drawing was just meant to be symbolic for the package type - silly me!

Thanks a lot for clarifying this for me, Wizard!

But, well, as three pins are NC, they could have packed it in a 5-pin package!
If anyone still can point me at other (maybe even more space economic) solution, I'd be thankful!

And, what R1 in the second schematic is for, I don't know, I found that circuit on the given site! I imagine that it is for damping the regulation.

Cheers!
Dominique

 

[AudioWizard]

If anyone still can point me at other (maybe even more space economic) solution, I'd be thankful!

I'm almost certain Maxim makes stuff that you'd like. I don't have much time roaming around their site, but go see there: http://www.maxim-ic.com/

They have a lot of components that are meant for battery-operated circuits in space-saving packages... So virtual grounds and inverters should be in their offering...

And, what R1 in the second schematic is for, I don't know, I found that circuit on the given site! I imagine that it is for damping the regulation.

I'd venture it is there to prevent oscillation; although I'm not sure what kind of oscillation could happen with a slow AOP in unity gain...

 

[Dominique]

I've just found one over at Maxim's, but it's way noisier than TI's IC... http://www.maxim-ic.com/appnotes.cfm/appnote_number/1199

I'll continue by checking the other popular IC makers...

Thanks again,
Dominique

 

[e39er]

TLE2426 Simulation

Has anyone tried simulating this circuit? I tried it but did not correctly get a split voltage. What leads should I be measuring against?

 

[peranders]

And, what R1 in the second schematic is for, I don't know, I found that circuit on the given site! I imagine that it is for damping the regulation.

(R1 = 10 ohms) It's for some protection but makes also the opamp less sensitive against capacitve load.