The 'drift' concept of the SDD (which was imported from particle physics) allows significantly higher count rates coupled with a very low capacitance of the detector.
In older detector designs, the collection electrode is centrally located with an external FET (field effect transistor) to convert the current into a voltage and thus represents the first stage of amplification.
Newer designs integrate the FET directly into the chip, which greatly improves energy resolution and throughput.
However, due to the smaller anode size, this leads to better energy resolutions (down to 123 eV for Mn Kα wavelength).
Combined with improved or adapted signal processing, it is possible to maintain the silicon drift detector's energy resolution up to 100,000 counts per second.