SLLA576 June   2022 DRV10987 , MCF8316A , MCT8316A

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Design Challenges and Solutions
    1. 2.1 Minimizing Motor Startup Time
      1. 2.1.1 Align
      2. 2.1.2 Initial Position Detect (IPD)
    2. 2.2 Minimizing Acceleration and Deceleration Slew Rate
    3. 2.3 Improving System Efficiency by Minimizing Power Losses
  5. 3References

2.3 Improving System Efficiency by Minimizing Power Losses

Power dissipation in MCT8316A can be from various sources such as RdsOn of the MOSFETs, MOSFET switching losses, MOSFET slew rate, operating supply current dissipation, and so forth. MCT8316A provides configurable options to minimize power losses and maximize thermal efficiency.

Power losses in MCT8316A can be minimized by configuring PWM output frequency, PWM mode, ASR and AAR.

Device case temperature drops by 8°C (from 72.3°C to 64.3°C) by configuring the following parameters:

  • Enable ASR [EN_ASR] and AAR [EN_AAR]
  • Decreased PWM output frequency [PWM_FREQ_OUT] from 50 kHz to 30 kHz.
  • Changed PWM mode [PWM_MODE] from Complimentary to Single ended mode.

Figure 2-5 shows the thermal image of MCT8316A at 50 kHz PWM output frequency, ASR and AAR disabled and PWM mode configured to Complimentary mode.

GUID-20220610-SS0I-RHPM-VQQ3-VDLZLX9JZMZF-low.png Figure 2-5 Thermal Image of MCT8316A – Higher Case Temperature

Figure 2-6 shows the thermal image of MCT8316A at 30 kHz PWM output frequency, ASR and AAR enabled and PWM mode configured to single ended mode.

GUID-20220610-SS0I-Q0M5-MTJB-LDQTJRMMSDLW-low.png Figure 2-6 Thermal Image of MCT8316A - Lower Case Temperature