Kontron KTQ45-FLEX - Manual (Page 44)

KTD-00782-I KTQ45 family Page 44 of 92
3.12 Fan Connector (FAN_CPU)
The FAN_CPU is used for the connection of the FAN for the CPU.
The FAN_SYS can be used to power, control and monitor a fan for chassis ventilation etc.
The 4pin header supports connection of 3-pin FAN, but it is recommended to use the 4-pin type for optimized
FAN speed control. The 3- or 4-pin mode is set in the BIOS setup menu.
4-pin Mode:
PIN Signal Type Ioh/Iol Pull
U/D Note
1 CONTROL O - -
2 SENSE I - 4K7
3 +12V PWR - -
4 GND PWR - -
Signal Description
CONTROL PWM signal for FAN speed control
SENSE
Tacho signal from the fan for supervision. The signals shall be generated by an open
collector transistor or similar. Onboard is a pull-up resistor 4K7 to +12V. The signal has to
be pulsed, typically twice per rotation.
12V +12V supply for fan. A maximum of 2000mA can be supplied from this pin.
GND Power Supply GND signal
3-pin Mode:
PIN Signal Type Ioh/Iol Pull
U/D Note
-
2 SENSE I - 4K7
3 +12V PWR - -
4 GND PWR - -
Signal Description
SENSE Tacho signal from the fan for supervision. The signals shall be generated by an open
collector transistor or similar. Onboard is a pull-up resistor 4K7 to +12V. The signal has to
be pulsed, typically twice per rotation.
12V
+12V supply for fan, can be turned on/off or modulated (PWM) by the chipset.
A maximum of 2000mA can be supplied from this pin.
GND Power Supply GND signal