A new, simplified, and more versatile current transient spectroscopy (CTS) measurement setup is demonstrated. With this setup, the depth profile of the platinum-hydrogen (PtH) defect in fully processed silicon high-voltage (HV) test diodes is investigated. It is shown that a proton field stop (FS) at the backside of these test devices suppresses the in-diffusion of hydrogen (H) leading to a significant reduction of the PtH defect concentration throughout the entire volume of the diode. Furthermore, a strong correlation of the depth profile of the PtH defect and the leakage current is observed. Thus, we conclude that the PtH defect is the main generation center in the investigated devices.