EUM6861/A/B/C
18V PWM Fan Motor Driver
DESCRIPTION
EUM6861/A/B/C is a fan motor driver for the single
coil brushless DC motor. With its high efficient direct
PWM control mode, EUM6861/A/B/C controls the
speed of brushless DC motor with a built in HALL IC
interface. EUM6861/A/B/C is suitable to drive variable
speed motors for personal computer’s power supply
radiation fans and CPU coolers.
EUM6861/A/B/C integrates PWM fan speed control,
minimum speed mode, soft start, fan tachometer, lock
protection, auto restart and Hall Bias functions. PWM
mode controls fan speed in low noise and low vibration
ways by adjusting RCTL voltage. EUM6861/A/B/C
can set minimum fan speed by presetting RMIN
voltage. With soft start function, EUM6861/A/B/C can
drive motor from slow speed to fast speed in a settable
time by setting the external capacitor between SS and
GND. If a fan motor is stalled by the external force or
obstacles, overdrive current may incur coil overheat
and burning. To prevent motor from overheating, the
lock protection circuit shuts down the internal power
devices for a few seconds after the motor lock is
detected. Then the auto restart circuit resumes to power
up the internal power devices. If the lock persists,
EUM6861/A/B/C shuts off power devices for a few
seconds. The lock protection delay time is externally
programmable by a capacitor. EUM6861/C has built in
motor rotation speed feedback (FG) output, motor
rotation detection (RD) output and Hall sensor bias
output.
FEATURES
Built in 18V Full-wave Motor Driver for Fan
Motor
Built in Input Surge Protection, No Zener Diode
Need
External Programmable Soft Start and Soft
Restart Function
Wide Input Range 3V~18V
PWM Fan Speed Control
Programmable Minimum Fan Speed
Built in Soft Switching Function
Built in Hall Bias
Lock Protection and Auto Restart
Fan Rotation Speed Feedback FG Output
(EUM6861/B/C)
Fan Rotation Detection RD Output
(EUM6861/A/C)
Thermal Shutdown Protection
Available in TSSOP-16 and TDFN-14 Packages
RoHS Compliant and 100% Lead (Pb)-Free
Halogen-Free
APPLICATIONS
Personal Computer’s Power Supply Radiation
Fans and CPU Coolers
Application Circuit
Figure 1. TSSOP -16 Typical Application Circuit
DS6861/A/B/C
Ver1.4
Feb. 2012
1
EUTECH [ EUTECH MICROELECTRONICS INC ]
