diff --git a/docs/en/hat/hat-rs485.md b/docs/en/hat/hat-rs485.md
index 6579bba7..3b701b6a 100644
--- a/docs/en/hat/hat-rs485.md
+++ b/docs/en/hat/hat-rs485.md
@@ -25,7 +25,7 @@ It is used to convert the TTL standard to the RS485 standard. If the outside ser
 - The built-in automatic transceiver circuit
 - Built-in DC-DC buck circuit
 - AOZ1282CI
-- input DC 5~12 V
+- input DC 12 V
 - BandRate up to 115200
 - Program Platform: Arduino, UIFlow(Blockly, Python)
 
diff --git a/docs/en/unit/rs485.md b/docs/en/unit/rs485.md
index e7c0ddc1..7395f701 100644
--- a/docs/en/unit/rs485.md
+++ b/docs/en/unit/rs485.md
@@ -17,7 +17,7 @@ It is used to convert the TTL standard to the RS485 standard. If the outside ser
 ## Product Features
 
 - Built in MAX485/SP485EEN
-- input DC 12~24 V
+- input DC 12V
 - Program Platform: Arduino, UIFlow(Blockly,Pyhton)
 - Two Lego-compatible holes
 - Product Size：32.2mm x 24.2mm x 10.5mm
diff --git a/docs/zh_CN/hat/hat-rs485.md b/docs/zh_CN/hat/hat-rs485.md
index 93e7e53e..de9e3c02 100644
--- a/docs/zh_CN/hat/hat-rs485.md
+++ b/docs/zh_CN/hat/hat-rs485.md
@@ -23,7 +23,7 @@ RS485是一种标准，用于定义串行通信系统的驱动器和接收器的
 - 内置自动收发电路
 - 内置DC-DC降压电路
 - AOZ1282CI
-- 输入电压: DC 5~12 V
+- 输入电压: DC 12 V
 - 波特率：115200
 - 开发平台: Arduino, UIFlow(Blockly, Python)
 
diff --git a/docs/zh_CN/unit/rs485.md b/docs/zh_CN/unit/rs485.md
index 5ed052a8..086f0bb2 100644
--- a/docs/zh_CN/unit/rs485.md
+++ b/docs/zh_CN/unit/rs485.md
@@ -13,7 +13,7 @@
 ## 产品特性
 
 - 内置 MAX485/SP485EEN
-- 输入 DC 12~24V 
+- 输入 DC 12V
 - 开发平台: Arduino, UIFlow(Blockly,Pyhton)
 - 2x LEGO 兼容孔