A modified switching scheme for multiplexer based thermometer-to-binary encoders

A modified switching scheme for thermometer-to-binary encoders used in time-to-digital converters (TDCs) is presented. The proposed scheme enables power savings up to 40% for a 256 bit encoder by taking advantage of the operating nature of the TDCs and by preventing unnecessary switchings to pass through the encoder tree. The efficiency of the proposed scheme is verified for thermometer encoders of different word lengths. It is observed that the power savings increase with the length of the thermometer encoder.