RT-ZL03 Rohde & Schwarz active logic probes for RTB2004 PCB photos

Bottom side
Top side

The most important components are the the 4 ADCMP562BRQ Dual High Speed Comparators which determine whether a signal is high or low. N5311 is an EN5311QI ENPIRION DC-DC CONVERTER. The 8-Pin SOIC seems to be Z8 Encore! XP F0823 Series 8-Bit microcontroller by Zilog, not sure what it does, but it seems a bit too powerful to just store a serial number or something like that.