On http://docs.particle.io/photon/ in the “Pins” section DAC is described as:
12-bit Digital-to-Analog (D/A) output (0-4095), and also a digital GPIO. DAC is used as DAC1 in software, and A5 is a second DAC output used as DAC2 in software.
But the adjacent graphic depicts DAC2 on A3, not on A5. Is this a documentation bug or am I misreading it? I’m just trying to help out.