MCT8317A datasheet(42/161 Pages) TI1

Part #	MCT8317A

Description	MCT8317A High Speed Sensorless Trapezoidal Control Integrated FET BLDC Driver

PDF	161 Pages

Scroll/Zoom	100%

Manufacturer	TI1 [Texas Instruments]

Direct Link	http://www.ti.com

Logo

42 / 161 page

Phase

Voltage A

Phase

Voltage B

Phase

Voltage C

Figure 8-28. 120o commutation in Mixed Modulation Mode

8.3.10.2 Variable Commutation

Variable commutation can be configured by setting COMM_CONTROL to 01b. 120o commutation may result in

acoustic noise due to the long Hi-Z period causing some torque ripple in the motor. In order to reduce this torque

ripple and acoustic noise, the MCT8317A uses variable commutation to reduce the phase current ripple at

commutation by extending 120o driving time and gradually decreasing duty cycle prior to entering Hi-Z state. In

this mode, the phase is Hi-Z between 30o and 60o and this window size is dynamically adjusted based on speed.

A smaller window size will typically give better acoustic performance. Figure 8-29 shows 150o commutation with

30o window size.

MCT8317A

SLLSFQ2 – JANUARY 2023

www.ti.com

Submit Document Feedback

Product Folder Links: MCT8317A

MCT8317A Datasheet(PDF) 42 Page - Texas Instruments