diff --git a/docs/assets/css/main.css b/docs/assets/css/main.css
index 06934c7a..72ca8e79 100755
--- a/docs/assets/css/main.css
+++ b/docs/assets/css/main.css
@@ -951,7 +951,7 @@ mark {
     display: -webkit-flex;
     display: flex;
     flex-direction:column;
-    z-index: 100;
+    z-index: 50;
     width: max-content;
 
 }
diff --git a/docs/assets/img/product_pics/unit/pahub/pahub_grove_a.png b/docs/assets/img/product_pics/unit/pahub/pahub_grove_a.png
deleted file mode 100644
index d1f5346f..00000000
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diff --git a/docs/assets/img/product_pics/unit/pahub/pahub_p4.jpg b/docs/assets/img/product_pics/unit/pahub/pahub_p4.jpg
new file mode 100644
index 00000000..70b31482
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diff --git a/docs/assets/img/product_pics/unit/pahub/pahub_p5.jpg b/docs/assets/img/product_pics/unit/pahub/pahub_p5.jpg
new file mode 100644
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diff --git a/docs/en/unit/pahub.md b/docs/en/unit/pahub.md
index bb9c6594..aafc5e47 100644
--- a/docs/en/unit/pahub.md
+++ b/docs/en/unit/pahub.md
@@ -54,7 +54,17 @@ The I2C address of this unit is 0x70 (changable by resistors).
 
 ## Schematic
 
-<img src="assets/img/product_pics/unit/pahub/pahub_sch.png">s
+<img src="assets/img/product_pics/unit/pahub/pahub_sch.png" width="50%">
+
+Referring to the schematic diagram and the TCA9548A data sheet, it can be seen that the Unit can modify the I2C address of the device by controlling the level combination of the A0 ~ A2 pins. (Default address is 0x70)
+
+Three chip resistance welding positions are reserved on the PCB of the Unit, which are A0-A2, as shown in the figure below.
+
+<img src="assets\img\product_pics\unit\pahub\pahub_p5.jpg" width="50%">
+
+After soldering a 0 ohm resistor, the corresponding pin will change from low to high, and the pin level combination and its corresponding I2C address are shown in the table below.
+
+<img src="assets\img\product_pics\unit\pahub\pahub_p4.jpg" width="50%">
 
 
 ## Example
diff --git a/docs/zh_CN/unit/pahub.md b/docs/zh_CN/unit/pahub.md
index 3624e82d..d0825405 100644
--- a/docs/zh_CN/unit/pahub.md
+++ b/docs/zh_CN/unit/pahub.md
@@ -30,7 +30,17 @@
 
 ## 原理图
 
-<img src="assets/img/product_pics/unit/pahub/pahub_sch.png">
+<img src="assets/img/product_pics/unit/pahub/pahub_sch.png" width="50%">
+
+参考原理图及TCA9548A数据手册可知，该Unit能够通过控制A0~A2引脚的电平组合，修改设备的I2C地址。(默认地址为0x70)
+
+在Unit的PCB板上预留了三个贴片电阻焊接位，分别为A0-A2，如下图所示。
+
+<img src="assets\img\product_pics\unit\pahub\pahub_p5.jpg" width="50%">
+
+焊接0欧电阻后，相应的引脚将由低电平变为高电平，引脚电平组合与其对应的I2C地址如下表所示。
+
+<img src="assets\img\product_pics\unit\pahub\pahub_p4.jpg" width="50%">
 
 ### 套件清单