Parallel Schottkys performance over single Shottkys app note (PDF) from NXP
This document gives an overview of power losses and the consequential junction temperature rise of two parallel Schottkys as secondary side rectifiers in flyback power adapters with up to 12.5 W output power. The focus is set on a comparison of the parallel configuration to a single rectifier under full load conditions. SPICE and thermal simulations were performed to calculate electrical power losses and the rise of junction temperatures above ambient.