分别画出霍尔传感器、磁敏电阻、差动变压器、光敏三极管和光耦的元件符号。

霍尔传感器：

     +Vcc
       |
       |
       |
       |
       |
       |
  _______ 
 |       |
 |       |
 |       |
 |_______|
       |
       |
       |
       |
       |
      OUT

磁敏电阻：

    +Vcc
      |
      |
      |
      |
      |
      |
  ___/ \___
 |         |
 |         |
 |         |
 |_________|
      |
      |
     OUT

差动变压器：

    +Vcc
      |
      |
      |
      |
      |
      |
  ___/ \___
 |         |
 |    A    |
 |         |
 |_________|
 |         |
 |    B    |
 |         |
 |_________|
      |
      |
     OUT

光敏三极管：

    +Vcc
      |
      |
      |
      |
      |
      |
   ___|___
  /      \
 |   LED  |
  \______/
      |
      |
   ___|___
  /      \
 |  PHOTO |
  \______/
      |
      |
     OUT

光耦：

    +Vcc
      |
      |
      |
      |
      |
      |
   ___|___
  /      \
 |   LED  |
  \______/
      |
      |
      |
      |
      |
   ___|___
  /      \
 |  PHOTO |
  \______/
      |
      |
     OUT