SLVUCC2 October   2021 MCT8316A

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Hardware Setup
      1. 1.1.1 Jumper Configuration
      2. 1.1.2 External Connections
  3. 2Quick Tuning
  4. 3Comprehensive Tuning
    1. 3.1 Cycle by cycle current limit
      1. 3.1.1 Selecting ILIMIT Pin Resistor
    2. 3.2 Motor Startup Settings
      1. 3.2.1 Motor Startup Profile
      2. 3.2.2 Motor startup method
        1. 3.2.2.1 Initial Position detect (IPD)
        2. 3.2.2.2 Double align
      3. 3.2.3 Selecting RMP_1 and RMP_2 Pin Resistors
    3. 3.3 Abnormal Speed Threshold
      1. 3.3.1 Selecting CONFIG_3 Pin Resistor
    4. 3.4 PWM Switching Frequency
      1. 3.4.1 Selecting CONFIG_1 Pin Resistor
    5. 3.5 Lead Angle
      1. 3.5.1 Steps to Tune Lead Angle
      2. 3.5.2 Selecting LDANGLE pin resistor
    6. 3.6 Slew Rate and Buck Voltage
      1. 3.6.1 Selecting SLEW_RATE Pin Resistor
  5. 4Revision History

3.5.1 Steps to Tune Lead Angle

To tune the lead angle, start with the default lead angle of 0 degrees by connecting LDANGLE pin to GND, then:

  1. Successfully run the motor at 100% speed

  2. Record the motor phase current (Iph).

  3. Record the frequency on the FG pin (fFG) which corresponds to the motor speed.

  4. Next, calculate the ratio of phase current over motor speed (Iph/ fFG)

Repeat steps 1 to 4 with lead angle of 10 degrees (populate 30 kΩ, ±5%) and 20 degrees (populate 91 kΩ, ±5%) in LDANGLE pin.

The lowest ratio of phase current over motor speed (Iph/ fFG) with the highest speed is the most efficient lead angle.