To begin the design process, a few parameters must be decided upon. The designer needs to know the following:
- Total resistance including power switch rDS(on), cable resistance, and the contact resistance of connectors
- The maximum continuous output current for the charging port. The minimum current-limit setting of TPS2549-Q1 device must be higher than this current.
- The maximum output current of the upstream dc-dc converter. The maximum current-limit setting of TPS2549-Q1 device must be lower than this current.