I tried quite hard to get this DAC operating on the 'native' USB power from my PC, but it proved not possible to attenuate the low frequency noise on the supply sufficiently. So I've gone for a step up voltage converter to boost the 5V rail to nearly 10V and then regulate it down again.

An LM2662 performs the step-up task admirably - chosen because its a switched capacitor kind of boost converter, rather than the more normal inductive boost circuit. Inductors tend to be rather leaky and I didn't want to radiate any ultrasonic magnetic field in the tight confines of this DAC's enclosure. Particularly as I have 4 inductors in the anti-imaging filter which are likely to pick up magnetic radiation to some degree.

The other bits on the board are a TL431 (6.6V) and two NPN pass transistors to provide supplies to the DAC array and I/V.