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class DAC – digital to analog conversion

The DAC is used to output an analog voltage based on a digital value.

The output voltage will be between 0 and 3.3V.

DAC is currently supported on ESP32 [1], SAMD and Renesas RA.

Note

The STM32 port has similar functionality to machine.DAC. See pyb.DAC for details.

Example usage (ESP32):

from machine import DAC

dac = DAC(pin)    # create a DAC object acting on a pin
dac.write(128)    # write a value to the DAC
dac.write(255)    # output maximum value, 3.3V

Constructors

class machine.DAC(id)

Construct a new DAC object.

id is a pin object (ESP32 and Renesas RA) or an index to a DAC resource (SAMD).

Note

On the ESP32, DAC functionality is available on pins 25 and 26. On the ESP32-S2, pins 17 and 18. See ESP32 Quickref for more details.

Note

SAMD21 has one DAC resource, SAMD51 has two. See SAMD Quickref for more details.

Methods

DAC.write(value)

Output an analog voltage to the pin connected to the DAC.

value is a representation of the desired output; a linear interpolation of 0-3.3V, though the range differs depending on the port and micro, see below:

Port/micro	Bits	Range
ESP32	8	0-255
SAMD21	10	0-1023
SAMD51	12	0-4095
Renesas RA	12	0-4095

Footnotes