45 lines
1.1 KiB
ReStructuredText
45 lines
1.1 KiB
ReStructuredText
Digital To Analog Converter
|
|
===========================
|
|
|
|
Overview
|
|
--------
|
|
|
|
ESP32 has two 8-bit DAC (digital to analog converter) channels, connected to GPIO25 (Channel 1) and GPIO26 (Channel 2).
|
|
|
|
The DAC driver allows these channels to be set to arbitrary voltages.
|
|
|
|
The DAC channels can also be driven with DMA-style written sample data, via the :doc:`I2S driver <i2s>` when using the "built-in DAC mode".
|
|
|
|
For other analog output options, see the :doc:`Sigma-delta Modulation module <sigmadelta>` and the :doc:`LED Control module <ledc>`. Both these modules produce high frequency PWM output, which can be hardware low-pass filtered in order to generate a lower frequency analog output.
|
|
|
|
|
|
Application Example
|
|
-------------------
|
|
|
|
Setting DAC channel 1 (GPIO 25) voltage to approx 0.78 of VDD_A voltage (VDD * 200 / 255). For VDD_A 3.3V, this is 2.59V::
|
|
|
|
#include <driver/dac.h>
|
|
|
|
...
|
|
|
|
dac_out_voltage(DAC_CHANNEL_1, 200);
|
|
|
|
API Reference
|
|
-------------
|
|
|
|
Header Files
|
|
^^^^^^^^^^^^
|
|
|
|
* `components/driver/include/driver/dac.h`
|
|
|
|
Enumerations
|
|
^^^^^^^^^^^^
|
|
|
|
.. doxygenenum:: dac_channel_t
|
|
|
|
Functions
|
|
^^^^^^^^^
|
|
|
|
.. doxygenfunction:: dac_out_voltage
|
|
|
|
|