Rockbox Development > New Ports

Fiio M3k

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benettonb1:
Awesome work! How does one go about installing this on the player?
b2b spice myfiosgateway com

amachronic:
Instructions here. If you have any trouble just ask.

aa666:
Hi!
isn't DAC power settings swapped?
second waveform corresponds to "Save battery" option, but it looks noticeably cleaner, then "high performance" one

//nevermind, looks like it's correct

amachronic:
I double checked the DAC code and datasheet and the DAC should be configured correctly in Rockbox. Except it should be powering down the HP amp channels when changing the power mode setting, but isn't. I'll fix that, but I doubt it's the culprit since the DAC is powered up in high-performance mode by default.

If you're right the datasheet is screwed up -- the meaning of the LPMODE bit is reversed and should be 1 for high performance instead of 0. If this is true, the power consumption of the DAC should be higher in 'battery saver' mode - hopefully it's enough of a change to make a difference on a battery bench run, but it'll take me a while to test that.

Forgive me if this should be obvious, but why is the RMS voltage 1.16 V on your scope? it's roughly double the rated RMS of the DAC.

EDIT: if you made a mistake then no worries.

aa666:
no mistakes
waveform looks cleaner in power save mode, and i have no idea why
but power consumption is less!
as for 1.16Vrms -
in datasheet: -1.5 dBFS, RL = 16Ω, HPG = +2 dB, THD+N < -20 dB | - 60 - mW
60mW at 16Ohm - that is 0.98Vrms, and i had no load
(those waveform were taken at volume level +2.5dB, at +3.0dB there are visible distortions already)

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