Step-up DC/DC dual Inverter Help

[LuisMCP]

I'm looking for an inverter boost/step-up DC/DC converter suitable for audio.
I must get +/- 12V from 5V for fed opamps.
The chip would be as little as possible, with a little current demand (100 mA at most)
I've seen the LT1945, LT3463 and LT3471 but it seems that it has a ripple of several mV at output.

I'm wondering for a more suitable chips (lower noise)

Thanks in advance 🙂

 

[JonSnell Electronic]

Secondary regulation will block any ripple. Set the outputs a few volts high and then use a series regulator on each rail to supply the required voltage.

 

[ssanmor]

You have a wide variety at Digikey, for example: 945-2001-5-ND

 

[LuisMCP]

Secondary regulation will block any ripple. Set the outputs a few volts high and then use a series regulator on each rail to supply the required voltage.

yes, I've think about this solution, but only in last instance. It needs two aditional chips and decoupling C's.

thanks.

 

[LuisMCP]

You have a wide variety at Digikey, for example: 945-2001-5-ND

RS3 series are big enough (better SMD for this application) and it seems some noisy too (20 mVpp)

Gracias.

 

[akis]

Can you not just use a 555 at say 30-50KHz and then a DC-DC using just capacitors (no coils)? With no coils present there will be very little EMF. There is another thread where Elvee showed us a very good DC Inverter circuit, which I have breadboarded and works quite well, you only need a step up and a positive side and it's done.