Induced electromotive
voltage detection
FR
FG
Forward
Stop
FHT
Float
FRT
Backward
Figure 7: FR and FG timing charts
FR
3
5KO
0.7Vcc
FR1
0.3Vcc
FR2
0.7VCC
0.3VCC
FR
FR1
FR2
Forward
Stop
(V-PMOS, W-NMOS Turn-on)
Floating
FRT
Reverse
Stop
(V-PMOS, U-NMOS Turn-on)
Floating
FRT
Reverse
LHT
LHT
When the motor is running Forward (FR<0.3Vcc) or Reverse (FR>0.7Vcc) , if FR goes
to the voltage between 0.3Vcc to 0.7Vcc, WT7062 will deliver a stop signal to hold the motor.
When the motor is hold (0.3Vcc < FR < 0.7Vcc), if FR goes to the voltage less than 0.3Vcc or
larger than 0.7Vcc, WT7062 will let the motor float for 1 Sec and then back to the forward or
reverse mode.
Weltrend Semiconductor, Inc.
Proprietary & Confidential
Mar. 4, 2011
Rev. 0.05
Page 7
WELTREND [ WELTREND SEMICONDUCTOR ]
