Hello guys,
One of my customers is considering using DRV8461 for their new products.
They have the following questions about switching loss calculation as the follows.
Could you please give me your reply?
Q1.
30kHz is used as PWM switching frequency in "8.2.4.3 Switching Loss" section.
What is this "PWM switching frequency"? Or where is this come from?
Q2. How is this "PWM switching frequency" calculated.
Your reply would be much appreciated.
Best regards,
Kazuya.
Hi Kazuya-san,
The PWM switching frequency is the switching frequency of the input signals.
The recommended switching frequency is 100kHz with an abs max of 500kHz.
The DRV8461 has a STEP/DIR interface. This means that a pulse will be sent to the STEP pin to trigger each step sequence of the stepper motor. The rising edge on STEP advances the microstep indexer, while the DIR pin sets the direction. The indexer table can be found on table 7.7 of the datasheet.
The PWM switching frequency is generated from an MCU and sent to the driver. The frequency is chosen depending on the desired output waveform and full-scale current.
Best,
David
