2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/117272We present a spectral analysis of 16 DAO white dwarfs from the Sloan Digital Sky Survey Data Release 4. With our NLTE H+He model grid, we derived photospheric parameters for these objects. We compare our new results to literature values and divide the DAOs into two distinct groups: post-AGB and EHB progenitors.4 pages, 2 figures, 1 table, to appear in the proceedings of the 15th European Workshop on White DwarfsAstrophysicstext