SLAU927B June 2024 – November 2024 MSPM0G3507
Base current represents the maximum measurable motor phase current in the motor control system. The user inputs the system base current (in Amps) in the currentBase parameter of the System Configuration page in GUI. The user can compute the system base current based on the current sense amplifier gain (CSAGAIN) in volts/amp and the full-scale ADC voltage (FSV) of 3.3V as shown in Equation 8. There is a factor of 2 considered to support bidirectional current sensing with 1.65V as the zero-current offset.
For example, in a system with CSAGAIN = 0.15V/A , the base current or maximum measurable system current by the ADC is 3.3V / (2 × 0.15V/A) = 11A.
If the system uses a current sense resistor (RSENSE) with CSAGAIN units mentioned in volts/volt (V/V), the CSA gain in volts/amp can be computed using Equation 9.