Phat DAC & BeagleBone



I’m working on a small project with a BeagleBone Black Wireless.
On this board the audio is generated in I2S format by the processor.

I got a PHAT DAC board with it that I want to use to test the I2S.

From the information found on the phat dac I got that i should use:

  • GND (phat pin 6, 39 <-> BBB P9_1 )
  • 5V (phat pin 2 & 4 <-> BBB P9_5 & P9_6)
  • 3.3V (phat pin 1 <-> BBB P9_3)
  • I2S LRCLOCK (phat pin 12 <-> BBB P9_28)
  • I2S SCLK / bitclock (phat pin 35 <-> BBB P9_31)
  • I2S data (phat pin 40 <-> BBB P9_29)

note BBBW schematics are here

But I still have no audio

Could someone confirm the wiring to me?
Did anyone ever did this before on this forum?

Thanks in advance

PS I’ve read this post on this forum: “phat-dac-which-gpio-are-in-use” for information as i did not find the PHAT DAC schematics and the pinout

PS2 sorry that the link to the forum is not an HTML link there is a limit of 2 links per post for me


Try wiring up every ground connection as documented on Pinout. (Ground connections in use are indicated by a small dark pip over the physical pin number.)

It could be that there are isolated grounds on the pHAT DAC.

Shamefully I haven’t fired up my Beaglebone Black in forever :(


i have connected the other grounds,
still nothing.

Is the schematic of the phat DAC available somewhere?