diff --git a/Documentation/iio/ad7380.rst b/Documentation/iio/ad7380.rst
index 9c784c1e652e9afc116fd206a6cdb70fa6e2adf0..6f70b49b9ef27c1ac32acaefecd1146e5c8bd6cc 100644
--- a/Documentation/iio/ad7380.rst
+++ b/Documentation/iio/ad7380.rst
@@ -41,13 +41,22 @@ supports only 1 SDO line.
 Reference voltage
 -----------------
 
-2 possible reference voltage sources are supported:
+ad7380-4
+~~~~~~~~
+
+ad7380-4 supports only an external reference voltage (2.5V to 3.3V). It must be
+declared in the device tree as ``refin-supply``.
+
+All other devices from ad738x family
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+All other devices from ad738x support 2 possible reference voltage sources:
 
 - Internal reference (2.5V)
 - External reference (2.5V to 3.3V)
 
 The source is determined by the device tree. If ``refio-supply`` is present,
-then the external reference is used, else the internal reference is used.
+then it is used as external reference, else the internal reference is used.
 
 Oversampling and resolution boost
 ---------------------------------