Updated documentation for pca9685 (#2325)

components/output/pca9685.rst

@@ -33,14 +33,35 @@ global ``pca9685`` hub and give it an id, and then define the
         pca9685_id: 'pca9685_hub1'
         channel: 0
 
+.. code-block:: yaml
+
+    # Example configuration entry with external clock enable and clock source from ESP32
+    pca9685:
+      - id: pca9685_hub1
+        external_clock_input: true
+
+    # Individual outputs
+    output:
+        # generate PWM from ESP32 ledc
+      - platform: ledc
+        pin: 25
+        id: extclk
+        min_power: 1
+        frequency: 40MHz
+
+      - platform: pca9685
+        pca9685_id: 'pca9685_hub1'
+        channel: 0
+
 Configuration variables:
 ************************
 
--  **frequency** (**Required**, float): The frequency to let the
+-  **frequency** (*Optional*, float): The frequency to let the
    component drive all PWM outputs at. Must be in range from 24Hz to
-   1525.88Hz.
+   1525.88Hz. Default ``1000Hz``.
+-  **external_clock_input** (*Optional*, bool): Enable external clock input. PRE_SCALE register will by set to 3. Default to ``false``.
 -  **address** (*Optional*, int): The I²C address of the driver.
-   Defaults to ``0x00``.
+   Defaults to ``0x40``.
 -  **id** (*Optional*, :ref:`config-id`): The id to use for
    this pca9685 component. Use this if you have multiple PCA9685s connected at the same time