The reference voltage, VREF, is applied externally and can be set up to the supply voltage, VDD.
基准电压(VREF)由外部提供，最高可以设置为电源电压VDD。
2
The rotor is aligned to a certain position specified in DC excitation mode for the period of (a), during which the IP pin voltage decreases from VREF to VREF/2 level.
在 IP 引脚电压从 VREF 降低至 VREF / 2 期间，在阶段（a）转子在直流励磁模式下对准某一指定的位置。