AN2527 Freescale Semiconductor / Motorola, AN2527 Datasheet - Page 2

• Manufacturer Part Number: AN2527
• Description: DC Motor with Dead-Time Correction - XOR version TPU Function Set
• Manufacturer: Freescale Semiconductor / Motorola

AN2527/D
2
voltage
voltage
voltage
motor
motor
motor
Positive current
Positive current
(Q2)
(Q2)
SW1
SW1
SW2
SW2
SW3
SW3
SW4
SW4
Negative current
(Q3)
SW1
SW2
SW3
SW4
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DC Motor with Dead-Time Correction – XOR version TPU Function Set (DCmDtXor) MOTOROLA
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- 50% PWM
- 50% PWM
- 50% PWM
PWM period
PWM period
PWM period
center-time
center-time
center-time
The dead-time correction technique requires knowledge the instantaneous
direction of the motor current. In case of positive motor current, the SW1 high-
time and SW4 low-time are equal to the calculated high-times, and the SW2
and SW3 channels control the dead-time. In the case of negative motor current,
the SW2 low-time and SW3 high-time are equal to the calculated high-times,
and the SW1 and SW4 channels control the dead-time. See
Freescale Semiconductor, Inc.
Figure 2. Dead-Time Correction Technique
For More Information On This Product,
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Go to: www.freescale.com
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voltage
voltage
voltage
motor
motor
motor
Positive current
(Q1)
SW1
SW2
SW3
SW4
Negative current
Negative current
(Q4)
(Q4)
SW1
SW1
SW2
SW2
SW3
SW3
SW4
SW4
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50% PWM
50% PWM
50% PWM
PWM period
PWM period
PWM period
center-time
center-time
center-time
Figure
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2.
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