An optical detector module can be used to implement proximity sensing function by detecting ambient light outside of the optical detector module in accordance with a first detection threshold. An optical detector module can be further used to implement other active functions such as material detection (e.g., skin) or depth-sensing by emitting one or more optical signals (e.g., light pulses at a specific wavelength) and detecting the reflected optical signals relative to a second and/or third detection threshold. The disclosure provides technical solutions for actively monitoring detection threshold(s) of an optical detector module to achieve better power management. In some embodiments, such solutions are useful for photodetectors having a wide sensing bandwidth, such as a photodetector formed in germanium or a photodetector comprising an absorption region comprising germanium.