A Novel Encoder for TDCs

  • Günter KnittelEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11444)


We present a novel encoder design for FPGA-based Time-to-Digital Converters (TDCs) that use tapped delay lines. The encoder is the most challenging and problematic unit on such measurement devices. Recent developments in TDC methodology include the Wave Union principle, and encoders based on population count. These two methods can alleviate fundamental disadvantages of FPGA-based TDCs. However, it appeared to be problematic to combine the two methods. The contribution of this paper is a special arithmetic unit that allows us to combine these two methods into a fast and compact encoder.

The paper is a report on work in progress, real-world measurement results cannot be given at this point in time.


TDC Wave Union Population count Encoder 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.GSI Helmholtzzentrum für Schwerionenforschung GmbHDarmstadtGermany

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