This paper describes a distributed master-slave multiphase DC-DC converter architecture and related digital control and communication techniques. In the distributed master-slave architecture, all converter modules are identical, but one module operates as the master. The master module communicates its voltage error and current data over a single-wire serial bus to remove the voltage sensing mismatch and to accomplish active current sharing among the modules. Experimental results are shown for a 5 V-to-12 V input, 1.3 V, 20 A output two-phase synchronous buck converter.