This paper presents a novel inductorless dual-mode buck-boost charge pump (CP) based DC-DC converter. The proposed architecture allows the same circuit to accomplish two modes of operation, buck and boost, for degrading or elevating the output voltage, respectively, compared to the input. To achieve each mode, only a switching of the input–output connections is needed without any other modification in the design of the DC-DC converter. The dual-mode configuration aims to merge two different functions into one circuit, minimizing the design time and the area the DC-DC converter occupies on the die. The proposed buck-boost CP has been designed using TSMC 65 nm complementary metal–oxide–semiconductor (CMOS) technology. The functional input voltage range of the CP in boost mode is 1.2 V to 1.8 V and the typical output voltage is 1.8 V. For the buck mode, the input voltage range is 3.2 V to 3.6 V and the output is 1.5 V. For both modes, the output can be easily modified to new values by changing the comparator configuration. Efficiency results are also provided for the two modes.

A dual mode buck-boost charge pump is presented in this paper. The two modes, buck and boost, of the CP can be used by the same circuit for degrading or elevating the output voltage, respectively, compared to the input. Each mode can be achieved by switching only the input-output connections without any other change in the design of the DC-DC converter. This dual mode configuration aims to merge two different functions into one circuit minimizing the area the DC-DC converter occupies on the die. The proposed buck-boost CP has been designed using TSMC 130nm complementary metal-oxide-semiconductor (CMOS) technology providing a 3.3V output voltage from a 2.2V supply voltage when the DC-DC converter operates in boost mode and a 1.6V output voltage from a 3.3V supply voltage in buck mode. A 2uF capacitor has been placed at the output of the CP. For the buck mode, the capacitor of the output must be pre-charged in order for the CP to operate properly.