Circuits for Low Power Bus Traffic Encoding

In modern circuits the fraction of total power attributed to wires is increasing. One method to decrease the power consumption is to reduce the number of transitions on long bus wires by encoding bus traffic. The presented circuit reduces the energy consumed by buses on a single die by caching the eight most recent values on both sides of a long bus and transmitting a low weight code word on a cache hit. A custom layout in .13μ process technology extracted and simulated indicates that our current optimized implementation offers net energy savings on buses longer than 15mm.