SLUSC60B December 2017 – October 2019 UCC28064A
The output capacitor ( COUT ) is selected based on holdup requirements, as shown in Equation 28.
Two 100-μF capacitors were used in parallel for the output capacitor.
For this size capacitor, the low-frequency peak-to-peak output voltage ripple (VRIPPLE) is approximately 14 V, as shown in Equation 30:
In addition to holdup requirements, a capacitor must be selected so that it can withstand the low-frequency RMS current (ICOUT_100Hz) and the high-frequency RMS current (ICOUT_HF); see Equation 31 to Equation 33. High-voltage electrolytic capacitors generally have both a low- and a high-frequency RMS current ratings on the product data sheets.