Low power high resolution TDC with fast data conversion for balloon-borne experiments

A new low power CAMAC TDC module with a resolution of 26 psec and fast data conversion for time-of-flight measurement on a balloon-borne particle detector is described. The module incorporates sixteen TAC channels in single CAMAC width, and the total power consumption is 0.8 W/ch. The temperature coefficient of the conversion gain is typically 20 ppm//spl deg/C so that an influence of a wide variation of the ambient temperature during the flight could be reduced. Each channel has a hit register scanned by a sequencer and digitizations of non-stopped channels are skipped, thus minimizing the conversion time and the data volume.