As a standard TDC, qutools' quTAU registers incoming signal events on 8 independent channels, records their exact time (bin size 81 ps) and channel number and communicates these to a PC. A graphical user interface is supplied for Windows® and Linux, software examples are available for C/C++ (Windows® and Linux) and Labview™.

For some applications it is not important to know the absolut time of its occurence, but only whether or not it appeared within a short timing window (the so-called coincidence window) around an event at another channel. For this purpose the user can set a coincidence timing window and then the quTAU counts events that happen individually or coincident with another event for the different combinations of channels (4 channels are used for this purpose). Because of the reduced amount of data, this mode can handle significantly higher event rates.