SLVSF16B January 2021 – April 2022 DRV8316
PRODUCTION DATA
The ILIM pin on the DRV8316 device is used to set a cycle-by-cycle current limit proportional to the voltage on the ILIM pin. The analog voltage ILIM can be set using a digital-to-analog converter from an external microcontroller or a resistor divider. Applying AVDD/2 on the ILIM pin disables the cycle-by-cycle current limit, and applying (AVDD/2 - 0.4) V on ILIM pin sets the current limit at the maximum threshold of 8-A.
Equation 26, Equation 27, and Equation 28 shows how to set the ILIM voltage with respect to AVDD = 3.3V to set cycle-by-cycle current limit to 2-A.
Use Equation 29 to calculate values for an AVDD-sourced resistor divider with resistors RILIM1 and RILIM2 to set ILIM equal to the 2-A calculated current limit.
To reduce current load on AVDD, RILIM2 is configured to be 10 kΩ as shown in Equation 30 and Equation 31.
Cycle-by-cycle limit can also occur with 100% PWM duty cycle inputs using an internal PWM pulse to monitor the current with ILIM. Setting the PWM_100_DUTY_SEL configures the frequency of the internal PWM pulse to 20kHz or 40kHz.