An Accelerator Chip for Ground-State Searches of the Ising Model with Asynchronous Random Pulse Distribution

We developed an SRAM-based CMOS LSI chip that accelerates ground-state searches of an Ising model. Escaping local minima is a key feature to create such a chip. We describe a novel method to escape the local minima by distributing random pulses asynchronously. The random pulses are input from outside of the chip and propagated through two asynchronous paths. In an experiment using a prototype chip, the method achieved the same solution accuracy as the conventional method. In addition, the solution accuracy was further improved by dividing the random pulse distribution path and by increasing the number of pseudo random number generators (PRNGs).