EUM6867
PWM Pre Driver for DC Fan Motor
DESCRIPTION
EUM6867 is a pre-driver for single coil brushless DC
motor, specially designed for 12V power supply
application. With an external PWM input signal,
EUM6867 can control the speed of DC motor. It is an
interface between a HALL IC and a single coil motor.
The functions built in EUM6867 include soft start
mode, PWM control mode, minimum speed mode,
soft-switching time, fan tachometer, lock protection,
auto restart, Hall Bias and current limiter.
PWM mode controls the external PMOS-NMOS FET
in low noise and low vibration. With soft start function.
EUM6867 can drive motor from slow speed to fast
speed in a settable time by setting the external
capacitor between SS and REG. Minimum speed mode
makes the lowest speed of motor settable.
Soft-switching time can cut the ineffective current
when phase change is not set. If the motor is stalled by
external force or obstacles, overdrive current may incur
coil overheating. To prevent this, the lock protection
circuit shuts down the external power devices for a few
seconds after the motor is locked. Then auto restart
circuit will resume to power up these devices. The
protection and power up time are settable by an
external capacitor. EUM6867 has FG output.
FEATURES
Single-phase full-wave Pre Driver
PWM Control Mode
Soft Start Function
Soft-Switching
Minimum Speed Settable
Lock Protection and Auto Restart
FG Output
Current Limit Protection
Available in TSSOP-16 Package
RoHS Compliant and 100% Lead (Pb)-Free
APPLICATIONS
Personal Computer’s Power Supply Radiation
and CPU Cooler
Application Circuit
Figure 1.
DS6867
Ver1.0
Feb. 2009
1
EUTECH [ EUTECH MICROELECTRONICS INC ]
