Table of Contents
Advertisement
FAN Connector
FAN Connector
CN32
Pin
Signal
1
GND
2
FAN_PWR
3
FAN_TACHO_IN
4
FAN_PWM
JP9 position
FAN driver mode selector
1-2
4-Wires Fan
2-3
3-Wires Fan
As stated above, by using a dedicate jumper JP9, it is possible to select if FAN_PWR is fixed to +12V_RUN, in order to support 4-wire tachometric fans, or must
be controlled by the signal FAN_PWMOUT, coming directly from COM Express
CCOMe-C79
CCOMe-C79 - Rev. First Edition: 1.0 - Last Edition: 1.0 - Author: A.R. - Reviewed by E.S. Copyright © 2021 SECO S.p.A.
Onboard it is available a 4-pin connector, type MOLEX p/n 47053-3000 or equivalent, for the connection of
tachometric FANs. Please be aware that the use of an external fan depends strongly on customer's
application/installation. Fan Speed control must be supported by COM Express module through signals
FAN_TACHIN and FAN_PWMOUT. Please refer to chapter 4.1 for considerations about thermal dissipation.
FAN_PWR: +12V_RUN derived power rail for FAN, managed by PWM signal FAN_PWMOUT coming from
COM Express connector. FAN_PWR is fixed +12V_RUN in 4-wires Fan, while is pulse width modulated via FAN_PWMOUT for
3-wires Fan
FAN_TACHO_IN: tachometric input from the fan to the COM Express module
FAN_PWM: PWM output to the fan, +5V_
Fan.
™
module, in order to support 3-wire tachometric fans.
-wires
60
Advertisement
Table of Contents
