The TPS62050 is a buck converter meaning it only switches when providing a Vo that is less than Vin. When Vin <Vo, this buck converter stops switching, turns on the top side FET so that Vo=Vin - Iload*Rds(fet). For buck and boost operation at your input…
Assuming you do NOT really need isolation, you could use either a SEPIC or a ZETA power stage that can take wide input range and either buck or boost the input to an output voltage inbetween, above or below it. Being a hysteretic converter/controller with…