simple PWM fan controller _for 4pin CPU fan_

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         simple PWM fan controller (for 4pin CPU fan)                                                                                                                D




                                                                               VDD=12V
                          VDD                                                                                                                   VDD

C                                                                            U1                                                                                      C
                                                    R1                   1                     8
                          CONTROL   N.C.                                      VDD    GND                                                        CONTROL
                                                    200
     mother board                                                        2
                                                                              GP5    GP0
                                                                                               7                                                               CPU
    (fan connector)                                                      3                     6                                                               fan
                          SENSOR                                              GP4    GP1                                                 N.C.   SENSOR
                                                                         4                     5
                                                                              GP3    GP2
                                                                    D1       PIC12F629/675                         SW1
                          GND                                                                                                                   GND
                                                                                                                   PUSH BUTTON SW
                                                          ZD 5.2V
B                                                                                                                                                                    B




                  typical fan cable color

                      1   GND       :      Black
                      2   VDD       :      Yellow                                    Title
                      3   SENSOR    :      Green                                              http://www.cepstrum.co.jp/
A                     4   CONTROL   :      Blue                                      Size           Number                                          Revision         A
                                                                                      Legal
                                                                                     Date:         4-Mar-2006                           Sheet of
                                                                                     File:                                              Drawn By:
                                                                                                   D:\new_home\hobby\pwmfan\pwmfan4pin.sch
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