A LEGO-Like Easy-Stacking Step-Up SC Converter with Ultra-High and Wide VCR Using All Input-Stress-Only Devices

High voltage conversion ratio (VCR) step-up DC-DC converters are widely used in micro-robot [1], [2], LED driver [3], [4], and energy harvesting applications [5]. For realizing both high efficiency and high power density, high VCR hybrid boost converters use both switched-capacitor and inductor to alleviate the efficiency drop mainly caused by the DCR losses [6], [7]. Fig. 1 top shows the weight and volume (off-chip passive components only) of the recently reported hybrid boost converters [2], [6], where the inductor and high-voltage capacitors are dominant contributors. Therefore, in order to further improve the power density, this work (Fig. 1 bottom) presents a cell/chip double-stacking switched-capacitor (DSSC) step-up converter with only 5V devices for >100V applications. Compared with prior stacking works [2], [8], this work has the following features. First, the proposed converter is implemented by multi-basic-cell stacking (BCS) with all input-stress-only devices and the proposed dual-PMOS level shifter (LS). Second, with the stacked LSs and drivers, the output voltage can be further boosted by three-wire easy multi-chip stacking (MCS). Third, although typical SC converters can only provide discrete VCRs, a reconfigurable high-VCR SC converter can maintain reasonably high efficiency over a wide V<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">OUT</inf> range because of the relatively fine <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_{1\mathrm{h}}$</tex> -related tuning steps.