7.3.5 Input Capacitor Selection

The TPSM84424 requires a minimum input capacitance of 20 µF of ceramic type. Use only high-quality ceramic type X5R or X7R capacitors with sufficient voltage rating. TI recommends an additional 100 µF of non-ceramic capacitancefor applications with transient load requirements. The voltage rating of input capacitors must be greater than the maximum input voltage. To compensate the derating of ceramic capactors, a voltage rating of twice the maximum input voltage is recommended. At worst case, when operating at 50% duty cycle and maximum load, the combined ripple current rating of the input capacitors must be at least 2 A(rms). Table 3 includes a preferred list of capacitors by vendor.