TB6537 Toshiba, TB6537 Datasheet - Page 7

• Manufacturer Part Number: TB6537
• Description: 3-Phase Full-Wave Sensorless Controller for Brushless DC Motors
• Manufacturer: Toshiba

5. Positional Variation
6. Overcurrent protection function
in connection with the frequency of PWM signal. Be especially careful when the IC is used for high-speed
motors.
is turned on by the timing of the next PWM signal.
Since positional detection is performed in synchronization with PWM signal, positional variation occurs
Variation is calculated by detecting at two consecutive rising edges of PWM signal.
1/f
An active phase which controls PWM is turned off by the rising-edge of the OC signal. The inactive phase
p
< Detection time variation < 2/f
Pin voltage
Positional signal
PWM signal
Reference voltage
Ideal detection timing
p
f
p
Pin voltage
: PWM frequency
7
Actual detection timing
TB6537P/F
2003-02-20