Fan Control Device with High Frequency PWM and Temperature Monitors
Datasheet
Appendix B Example Fan Circuits
The following figures show examples of circuitry on the board for the PWM outputs, tachometer inputs,
and remote diodes. Figure B.1, "Fan Drive Circuitry (Apply to PWM Driving Two Fans)" shows how the
part can be used to control four fans by connecting two fans to one PWM output.
Note: These examples represent the minimum required components. Some designs may require
additional components.
12
V
3.3V
3.3V
1k
2.2k
PWMx
MMBT390
4
M
MMBT222
2
Fan
1
M
MMBT222
2
Fan
2
Figure B.1 Fan Drive Circuitry (Apply to PWM Driving Two Fans)
SMSC EMC2300
Revision 0.2 (06-14-06)
DATA7S9HEET
SMSC [ SMSC CORPORATION ]
