Add X9C potentiometer docs (#2541)

components/output/x9c.rst

@@ -0,0 +1,56 @@
+X9C Potentiometer Output
+========================
+
+.. seo::
+    :description: Instructions for setting up a X9C digital potentiometer with ESPHome.
+    :image: description.svg
+
+The ``x9c`` output platform allows you to an output that controls a `X9C digital potentiometer <https://www.renesas.com/us/en/document/dst/x9c102-x9c103-x9c104-x9c503-datasheet>`__.
+
+.. figure:: images/x9c.jpg
+    :align: center
+    :width: 70.0%
+
+    X9C digital potentiometer
+
+The X9C family of digital potentiometers are available in different resistance values.
+
+==================== ===================== 
+``X9C102``           ``1kΩ``
+-------------------- ---------------------
+``X9C103``           ``10kΩ``
+-------------------- ---------------------
+``X9C503``           ``50kΩ``
+-------------------- ---------------------
+``X9C104``           ``100kΩ``
+==================== =====================
+
+All chips are controlled by a three wire interface and feature 100 possible wiper positions.
+
+.. code-block:: yaml
+
+    # Example configuration entry
+    output:
+      - platform: x9c
+        id: x9c_pot
+        cs_pin: GPIO25
+        inc_pin: GPIO27
+        ud_pin: GPIO26
+        initial_value: 0.5
+
+Configuration variables:
+------------------------
+
+- **id** (**Required**, :ref:`config-id`): The id to use for this output component.
+- **cs_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): Chip Select pin
+- **inc_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): Increment pin
+- **ud_pin** (**Required**, :ref:`Pin Schema <config-pin_schema>`): Up/Down pin
+- **initial_value** (*Optional*, float): Manually specify the initial potentiometer value, between ``0.01`` and ``1.0``. Defaults to ``1.0``.
+- All other options from :ref:`Output <config-output>`.
+
+See Also
+--------
+
+- :doc:`/components/output/index`
+- :apiref:`x9c/x9c.h`
+- :ghedit:`Edit`

index.rst

@@ -447,6 +447,7 @@ Output Components
     Template Output, components/output/template, description.svg
     BP1658CJ, components/output/bp1658cj, bp1658cj.svg
     BP5758D, components/output/bp5758d, bp5758d.svg
+    X9C Potentiometer, components/output/x9c, x9c.jpg
 
 Light Components
 ----------------