A Wireless Data and Power Transfer-Enabled MCU for Shape-Configurable Chiplet-Based Computers

In this paper, we propose a shape-configurable chiplet-based computer for the easy construction of embedded computing systems with diverse functions and shapes. Adjacent chips are connected via a wireless bus that uses base-band data transfer through inductive coupling between on-chip coils. Power is wirelessly supplied to each chip through inductive coupling between coils on the board and on the chip. By combining multiple chiplets, it is possible to construct systems with various functions and shapes. The wireless connectivity and power supply facilitate easy functional modifications, additions, and fault management of the system. A challenge in realizing such a system is the electromagnetic interference between wireless data and power transfer. This paper investigates the interference between coils designed for broadband wireless data transfer and coils designed for narrowband wireless power transfer. Furthermore, we designed a test chip using $0.18-\mu \mathrm{m}$ CMOS technology, which integrates a 32 -bit MCU, wireless data transfer circuits, and wireless power transfer circuits. By mounting two test chips on the same board, we demonstrated through measurements that inter-chip wireless data transfer is feasible during wireless power transfer.