8.2.2 Detailed Design Procedure

The TPS6302x series of buck-boost converter has internal loop compensation. Therefore, the external inductor and output capacitors have to be selected to work with the internal compensation. When selecting the external components, a low limit for the inductor value exists to avoid subharmonic oscillation which can be caused by a far too fast ramp up of the inductor current. For the TPS6302x series, the inductor value must be kept at or above 1 µH.

In particular, either 1 µH or 1.5 µH is recommended working at an output current between 1.5 A and 2 A. If operating with a lower load current, it is also possible to use 2.2 µH.

Selecting a larger output capacitor value is less critical because the corner frequency moves to lower frequencies.