PWM Pre Driver for DC Fan Motor
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 S-S and 5VREG. 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 overheat/burning. To prevent this, lock protection
circuit can shut down the external power devices for a
few seconds after motor lockup. Then auto restart
circuit will try to power up these devices. The
protection and power up time are settable by an
external capacitor. EUM6867 has FG output.
z Single-phase full-wave Pre Driver
z PWM Control Mode
z Soft Start Function
z Soft-Switching Time
z Minimum Speed Settable
z Lock Protection and Auto Restart
z FG Output
z Current Limit Protection
z Available in TSSOP-16 Package
z RoHS Compliant and 100% Lead (Pb)-Free
z Personal Computer’s Power Supply Radiation
and CPU Cooler
DS6867 Ver0.1 Nov. 2007