Would you pls help DRV8899 as below? thanks.
1.VREF and STEP are relative or independent? Will it influence speed? Will it influence current?(Start up will be max. current, increase speed will reduce current?)
2.Will VREF circuit are different for DAC or PWM?
3.Can we use voltage divide for VREF design?
4.Can VREF not control if using SPI Interface?
5.Will Step motor need to consider current ripple?
6.What is Decay Modes?