This paper presents an efficient and compact offline chip-scale power supply in 0.18µm high-voltage (HV) silicon-on-insulator (SOI) technology, suitable to supply IoT nodes, sensors, RF transceivers, LED strings, etc. from the 120/230V AC mains (Fig. 14.2.1). Main innovations include a voltage-interval-based dual-mode AC-DC conversion and an active zero-crossing buffer in the AC interface, which significantly reduces the size of the HV buffer capacitor Cb and enables on-chip integration. The converter supports both AC-DC and DC-DC conversion with an input voltage range of 15 to 325V. Prior-art integrated converters use capacitive or direct (resistive) coupling in the ACinterface. Capacitive coupling at 50/60Hz gives either very little power (below 20µW) in case of fully integrated capacitors [1-3] or requires very large discrete capacitors [3,4]. Direct coupling achieves mW output power [5,6], however, such designs still need large
Christoph Rindfleisch, Bernhard Wicht
Leibniz University Hannover, Hannover, Germany