Dr. Winstead will present research on energy limits in error correcting decoders at the 2014 International Zurich Seminar on Communications (IZS). This research was done in collaboration with Prof. Christian Schlegel of the Ultra-Marine Digital Communication Center, Dalhousie University, Canada. Our article considers the effects of the Shannon-von Neumann-Landauer (SNL) limit on a particular type of message-passing decoder for low-density parity-check (LDPC) codes. The SNL limit predicts the minimum possible energy required to reliably perform a binary computation or transmission. We adapt this principle to consider the effects of thermal noise errors within an LDPC decoder. Using this approach, we are able to predict an "ultimate tradeoff" between energy and reliability in the decoding circuit. This result is "ultimate" in the sense that it is a limit for all possible implementation technologies. The conference will take place Feb. 26-28, and the article will be open access.