In article , ian@morse-
code.NO.SPAM.TODAY.fsnet.co.uk says...

I'd like to build a tone control circuit using the LF353 dual op amp.
The circuit has bass, mid range and treble adjustments.

snippety

though for line input levels, this will probably work down to +8 and
-8 volts. But I want to run it from a single +12 volt supply.

snippety-two

The solution: You can easily get aftermarket DC/DC converter
modules which will take your +12 in, and provide bipolar 15V out.

Some examples:

Power-One, p/n DFC10U24D15, in stock at DigiKey for about $71. Vin
range of 9-36, Vout +/-15 at 300mA per, isolated outputs. .PDF spec
sheet is at:

http://www.power-one.com/resources/p...eet/dfc10d.pdf

A less expensive solution with slightly lower output voltages can
be found at Jameco on this link.

http://www.jameco.com/webapp/wcs/sto...play?langId=-1
&storeId=10001&catalogId=10001&productId=161728&pa =161728PS

If the link doesn't work, try searching for Mean Well part
#DKE15A-12. This one will give you +/-12V at 625mA each, isolated
output, for $35 and change.

I'm sure there are plenty of other manufacturers with products
that can address your application. Happy hunting.


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