mc68hc708mp16 Freescale Semiconductor, Inc, mc68hc708mp16 Datasheet - Page 149

• Manufacturer Part Number: mc68hc708mp16
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

9.6.3 Top/Bottom Correction
MC68HC708MP16
Freescale Semiconductor
—
Rev. 3.1
In a half-bridge AC motor drive, either the top or the bottom transistor
controls the output voltage at any given time. The direction of the motor
current determines which transistor controls the output.
During deadtime, both transistors in a half-bridge are off, allowing the
load voltage to float and introducing distortion in the output voltage.
NEGATIVE CURRENT
POSITIVE CURRENT
Pulse Width Modulator for Motor Control (PWMMC)
PWM TO BOTTOM
LOAD VOLTAGE
LOAD VOLTAGE
LOAD VOLTAGE
PWM TO TOP
TRANSISTOR
TRANSISTOR
DEADTIME
DESIRED
Figure 9-18. Deadtime Distortion
Figure 9-17. Current Convention
Pulse Width Modulator for Motor Control (PWMMC)
POSITIVE CURRENT
NEGATIVE CURRENT
Technical Data
CURRENT
POSITIVE
NEGATIVE
CURRENT
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