A digital/analog converter (30) with a first return-to-zero unit (311) which is connected to a first busbar (321), wherein the first busbar (321) is connected in each case to a first output of several differential units (351, 352, 35n). In this context, the first return-to-zero unit (311) provides at least one clock input which is directly or indirectly connected to a first photodiode, wherein the first photodiode is fed from a pulsed light source (5).