The same as a full DiRICH-System, only in 1/10 of the volume and optimized for SiPM arrays. So, 384 channels on an area of 5.5cm x 8cm.
The DiRICH5s1 is just like the DiRICH3-5, but it its own optical transceiver and the power connector (with trigger and clock) on board, therefore it is standalone and doesn't need a backplane.