SNVSBJ0A December 2019 – June 2020 LM5170
In addition to a fixed dead time programming by RDT, the dead time can be dynamically adjusted either by applying an analog voltage or a PWM signal as shown in Figure 45. Varying the analog voltage or the duty ratio of the PWM signal will adjust the DT programming. For analog adjustment, a single stage RC filter is recommended to filter out any possible noise. For PWM adjustment, a two-stage RC filter is recommended to minimize the ripple voltage resulted on the DT pin.
When an analog voltage is applied, the resulted dead time is determined by Equation 19:
When a PWM signal is applied, the resulted dead time is determined by Equation 20: