EUM6804
PWM Fan Motor Driver with Slope
Control and Low Duty Startup
DESCRIPTION
EUM6804 is a fan motor driver for brushless DC fan
motor. It integrates three types speed control modes,
low duty startup function, soft switched output, lock
protection, Hall bias, FG output, shutdown mode,
quick restart and TSD. With these modes and functions,
EUM6804 can not only be applied to DC fans which
require different speed curves, but also be applied to
NB and other portable equipments which require
silence and low power dissipation.
The three types speed control modes are PWM control
mode, VCC control mode with slope adjustable,
normal VCC control mode. Low duty startup function
makes it possible for DC fan to start and restart under a
very low PWM duty cycle. Soft switched output drives
DC fan in low noise and low vibration. If a DC fan 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. EUM6804 has built in Hall IC bias output,
motor rotation speed feedback (FG). With its shutdown
mode and quick restart, EUM6804 consume little
power dissipation during shutdown time and can be
started at once regardless of lock detection time.
FEATURES
Single-Phase Full-Wave Driver System
Three Speed Control Mode
PWM Control Mode
VCC Control Mode with Slope Adjustable
Normal VCC Control Mode
Low Duty Startup
SD = H: Enable Low Duty Startup
SD = L: Disable Low Duty Startup
Soft Switched Drive for Silent Application
Lock Detection and Automatic Restart
Shutdown Mode and Quick Restart
Low Standby Current (PWM = L)
FG Output
Hall Bias Output
Thermal Shutdown Protection
Available in UDFN-10 Package
RoHS Compliant and 100% Lead (Pb)-Free
Halogen-Free
APPLICATIONS
NB Cooling Fan
Silent Fan Motor
Application Circuit
Figure 1. PWM Control Mode
DS6804
Ver0.1
Apr. 2011
1
EUTECH [ EUTECH MICROELECTRONICS INC ]
