diff --git a/USB-protocol.md b/USB-protocol.md
index 404ecb4..f73296b 100644
--- a/USB-protocol.md
+++ b/USB-protocol.md
@@ -189,7 +189,7 @@ __**Voltage settings**__:
 |         3.6 | `0x8d 0x4b`      | `0x8d 0x4f`    |
 |         5.0 | `0xc4 0x4b`      | `0xc4 0x72`    |
 
-The first byte of the voltage is equal to `floor(voltage * 39.2)`. In idle mode, the second byte is always `0x4b`, but during a capture it varies, with an unknown logic behind it, increments are non-monotonous.
+The first byte of the voltage settings is equal to `floor(max_voltage * 39.2)`. The second byte is the threshold voltage. In idle mode, the second byte is always `0x4b` (1.9V), but during a capture it varies. For some reason, it isn't always half the maximum voltage, sometimes it's above it, sometimes below.
 
 The default settings blob used seems to be `01 04 00 00 00 90 d0 03 90 d0 03 e8 6e f3 00 00 f0 0f 0f 81 4b 32 01 00`.