tb6548f TOSHIBA Semiconductor CORPORATION, tb6548f Datasheet - Page 6

• Manufacturer Part Number: tb6548f
• Description: Three-phase Full-wave Pwm Sensorless Controller For Brushless Dc Motors
• Manufacturer: TOSHIBA Semiconductor CORPORATION

5. Positional Variation
in connection with the frequency of PWM signal. Be especially careful when the IC is used for high-speed
motors.
Since positional detection is performed in synchronization with PWM signal, positional variation occurs
Positional signal
Variation is calculated by detecting at two consecutive rising edges of PWM signal.
1/f
p
PWM signal
Output voltage
of TA84005F
< Detection time variation < 2/f
Reference voltage
Ideal detection timing
p
Pin voltage
f
p
: PWM frequency
6
Actual detection timing
2001-08-28
TB6548F