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+-15v Bipolar supply dc-dc converter selection

Other Parts Discussed in Thread: TPS7A33, LMZ34002, DCP021515

Hello:


I need to derive +-15v (30-100 mA per rail) and 48v (50mA) for an audio circuit. The outputs will feed into a pi filter and then into  tps7a33/ tps7a470 regulators.

Vin is flexible tailored to whichever converter I wind up using. It might wind up being a usb battery.
Are these types of batteries inherently less noisy than a switching power supply ? I'm not sure if these have switching regulators on them.

Currently I am looking at 2 converters and have questions about their relative merits. It would be great to have only one converter series/type for all three rails but it doesn't look like this is possible - ?

lmz34002: not very diy friendly footprint and complicated layout. positives: small, ample current and voltage. What is the minimum load to ensure constant 800khz switching frequency?

dcp02 series: easier diy footprint. It looks like there is  constant switching frequency of 400khz. In general for audio do you want to pick the highest switching frequency to keep things as far out of the audio band or is anything over 200-300k fine?

Along the same line there is the TPS6513x series with guaranteed >1Mhz switching frequency.

Also, keeping in mind that I will have yet another converter somewhere to boost Vin to 48V, how important is keeping all switching frequencies equal to avoid beats/sympathetic oscillation? This is potentially one advantage to using multiple dcp02 series for all rails due to its sync pin.

On the dcp021515 the minimum output voltage is +-14.25. This would be followed by the tps7a471 regulator which I think has something like 300mA minimum drop. Do I have to account for worst case of 14.25v and then regulate ~ 13.8v? Or should i breadboard one first and measure?