Precision timing control system

Operation of the CESR storage ring with complex bunch patterns has made necessary more flexible timing controls. Multiple trains of bunches based on a fundamental spacing of 14 ns are used in both the injector and the storage ring. Hence, a generally programmable trigger pattern is needed for electron gun pulsing, beam detection, beam feedback gating, and RF phase control. To achieve this, an upgrade of the previous CESR timing system using small-feature CMOS logic has been built. The new system has a time delay resolution of 10 ps and RMS jitter of 14 ps. The delay transfer function is linear to within 30 ps, and is monotonic over 32 bits of range. The use of programmable large-scale integrated circuits and the VME packaging system results in a system that is contained in 4 crates and occupies a fifth of the volume of its predecessor.