A Development of Front-end Electronics System Adopting Pipeline Transfer

我们开发了一种新的数据采集系统，该系统具有独特的前端模块流水线操作方案。我们在TKO BOX系统上实现了前端信号处理的流水线架构。TKO盒系统最初是为KEK的特里斯坦实验而设计的，TKO模块的操作可分为采样保持、A/D转换和数据读出三个阶段。这三个阶段之间的流水线传输使得在数据读出期间处理下一个事件成为可能。结果，由于读出而导致的死区时间显著减少。该方案适用于不带Flash ADC_S的常规模块。为简单起见，我们采用了最小流水线方案。为了实现这一方案，我们修改了TKO规范，开发了新的TKO前端模块、新的门控制器和触发监控器，并在KEK PS上测试了这种新的数据采集方案，用于热量计校准。测试系统使用了3个TKO盒，扫描所有通道的时间为512毫秒。在500赫兹的触发频率下，死区时间为7.2%，其中100毫秒的A/D转换死区时间为4.6%，而在没有流水线操作的情况下死区时间高达23.4%。该系统工作良好，在三个月的校准运行中没有发生严重错误。

We have developed a new data acquisition system, which has a unique pipeline operation scheme for front-end modules. We have implemented a pipeline architecture for front-end signal processing on the TKO BOX system. TKO BOX system was originally designed for TRISTAN experiments at KEK.Operations in TKO modules can be divided into three stages : sample-and-hold, A/D conversion, and data read-out. Pipeline transfers between these three stages make it possible to process the next event during data read-out. As a result, dead-time due to read-out is significantly decreased. This scheme is applicable to conventional modules without flash ADC_S. We have adopted a minimal pipeline scheme for simplicity. In order to realize this scheme, we have modified TKO specification and developed new TKO front-end modules, a new gate controller, and a trigger supervisor.We have tested this new data acquisition scheme for calorimeter calibration at KEK PS.Three TKO BOXes were used for the test system, and it takes 512msec to scan all channels. At a trigger rate of 500 Hz, dead-time is found to be 7.2% including dead-time of 4.6% due to A/D conversion of 100msec, while dead-time comes up to 23.4% without pipeline operation. The system worked very well and no critical errors occurred in three months of calibration run.