There is an optimized performance in this voltage regulator because it utilizes the Tape and Reel package. In this case, DC DC switching regulator has 1 outputs configured to it. DC DC switching regulators like this one generate Fixed outputs on their output pins to handle the power management. It has a 5-pin voltage regulator dc to dc.
RSS-0905/H-R Features
1 outputs
RSS-0905/H-R Applications
There are a lot of RECOM Power RSS-0905/H-R Voltage Regulators applications.