5.2 ADC Configuration
Each PWM channel on a 32-bit microcontroller is capable of independently triggering an ADC conversion on any of the analog input. Integrated PFC and sensorless FOC implementation requires to sense six analog inputs, as shown in Table 5-2. PFC-related analog input conversions are triggered simultaneously by PFC PWM Channel and sensorless FOC-related analog input conversions are triggered simultaneously by any one of the three FOC PWM Channels. Although DC Bus Voltage sensing is required for both PFC and FOC, its analog conversion is triggered by PFC PWM channel as PFC control loop runs at faster rate than FOC control loop.
Analog Input | Application | ADC Module | ADC Trigger | Sample Rate |
---|---|---|---|---|
AC Line Voltage | PFC | ADC4 | PFC PWM Channel | 40 kHz |
PFC Inductor Current | PFC | ADC0 | PFC PWM Channel | 40 kHz |
DC Bus Voltage | PFC/FOC | ADC7 (Shared ADC) | PFC PWM Channel | 40 kHz |
Phase A Motor Current | FOC | ADC3 | FOC PWM Channel | 20 kHz |
Phase B Motor Current | FOC | ADC1 | FOC PWM Channel | 20 kHz |
Speed Reference Potentiometer | FOC | ADC7(Shared ADC) | FOC PWM Channel | 20 kHz |