Abstract: In the paper a CAMAC quad TDC is described. It converts nanosecond timeintervals into digital signals. It has two ranges: 102ns and 510ns. Each range has2047 counts, the time resolution is 50ps or 250ps respectively and the former maybe changed to 40 ps. The TDC has more CAMAC functions. The principle, blockdiagram, CAMAC functions and features of the TDC are described.