Methods and apparatus relating to low cost and/or low overhead serial interface for power management and other IC (Integrated Circuit) devices are described. In an embodiment, a unique address is assigned to each of a plurality of slave devices. The plurality of slave devices are coupled in a daisy chain configuration. And, any access directed at a first slave device from the plurality of slave devices is allowed based at least in part on comparison of an address of the first slave device and an address associated with the access. Other embodiments are also disclosed and claimed.