On 23/08/2019 13:24, A. Dumas wrote:
> Op 23-08-19 om 12:59 schreef The Natural Philosopher:
>> On 23/08/2019 11:26, A. Dumas wrote:
>>> Audio
>>> circuit schematic for the Pi4 at the bottom centre here:
>>>
https://www.raspberrypi.org/documentation/hardware/raspberrypi/schematic/rpi_SC
H_4b_4p0_reduced.pdf
>>> (audio is identical on the 3 en 4 but they cleaned up the drawing a
>>> bit in this version)
>>
>> Where is the rest of the schematic? What drives PWM1_MOS1 and 2?
>
> Mostly proprietary SoC, Broadcom ARM version with their VideoCore GPU. I
> have no idea what's in there, but the Pi doesn't have hardware PWM or
> analogue gpio pins.
>
So its a 1 bit per channel software DAC

> https://en.wikipedia.org/wiki/Raspberry_Pi#Specifications


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