Low power TAC & QVC circuits for balloon borne experiments

TAC (time-to-amplitude converter) and QVC (charge-to-voltage converter) circuits have been developed for balloon-borne experiments. The aim of the development is to reduce power consumption. The circuits were optimized by a simulation program on a workstation. The TAC measures a time interval and QVC measures an amount of charge. The time resolution of the TAC is 2 ns/count for a full scale of 8 μs (12-b). The power consumption is 55 mW/channel. The QVC offers a resolution of 0.6 pC/count for a full scale of 1200 pC(11-b) and consumes 80 mW/channel. It is concluded that the design goals of the simulation have been achieved in the prototype TAC and QVC circuits