diff --git a/README.md b/README.md
index f33862a87..5c5658f42 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,7 @@ ESP32-C3 is a cost-effective, RISC-V-based MCU with Wi-Fi and Bluetooth 5 (LE) c
 | Variable | Parameter | min | Typ | max | Unit |
 | --- | --- | --- | --- | --- | --- |
 | V<sub>IH</sub> | High-level Input voltage | 0.75xV<sub>DD</sub> | - | V<sub>DD</sub> + 0.3 | V |
+| V<sub>IL/sub> | Low-level Input voltage | -0.3 | - | 0.25xV<sub>DD</sub> | V |
 
 ### Programming via UART