MIMO Switched-Capacitor converter using only parasitic capacitance with Scalable Parasitic Charge Redistribution

Abstract

In this work a Multiple-Input Multiple-Output (MIMO) Switched-Capacitor (SC) converter is presented that generates Multiple DC voltages using only the parasitic capacitances already present in fully-integrated SC converters. In combination with the Scalable Parasitic Charge Redistribution technique, the presented MIMO converter can provide voltage rails for control blocks or clock generation in low-power SC converters, without any area overhead. The proposed converter only makes use of existing blocks and therefore only adds conductive losses, which means that for low output powers, efficiencies close to 100% can be achieved. A theoretical analysis of the converter is given and used to prove the efficiency of the converter compared to regular SC MIMO converters. The working principle of the proposed MIMO converter is verified with measurements, demonstrating a peak efficiency of 98.9%.

MIMO Switched-Capacitor DC–DC Converters Using Only Parasitic Capacitances Through Scalable Parasitic Charge Redistribution

“…2) Use Case based: The topologies' normalized conductive losses are compared for three different node current profiles, each of which corresponds to a specific use case. Table II gives an overview of the used current profiles, which are, unlike in [32], further normalized such that the total output power in each case is the same. These consist of two multiple-output cases and one where the MIMO converter is used to supply a single voltage corresponding to a VCR of 2:1.…”

Fully integrated power management: The missing link?

“…In addition, SPCR can create multiple additional DC voltage rails spread out evenly across the flying capacitor's BP node's swing, each of which can source or sink current [12]. As such, SPCR can also be thought of as a multiple-input-multipleoutput (MIMO) DC-DC converter that uses only parasitic capacitance.…”