A 12-V Single-Input Multiple-Independently Configurable-Output Dynamic Voltage Scaling Supply in Standard 0.18-μm CMOS for Electrical Stimulation Applications

This letter presents the design and implementation of a single-input multiple-independently configurable-output (SIMICO) dynamic voltage scaling supply (DVSS) for multiple-channel electrical stimulation applications. The proposed SIMICO DVSS mainly consists of a 3-stages charge pump (CP) and 16 low-voltage (LV) compatible 5:1 power multiplexers (MUXs). The 3-stages CP is supplied by a single supply VDD and capable of outputting four voltage levels VDD, 2
$\times $
VDD, 3
$\times $
VDD, and 4
$\times $
VDD. Each of the 16 LV compatible 5:1 power MUX can be independently configured to connect its output to GND or one of the four generated voltage levels from the CP, which enables individual channel supply control (ICSC) for multiple-channel stimulation applications. The proposed circuit achieves maximum 12-V output voltage and 1-mA output current with maximum 32% energy reduction compared to the conventional DVSS architecture. This design is implemented in SMIC standard 1.8/3.3 V 0.18-
$\mu \text{m}$
CMOS process occupying a core area of
$1500\,\,\mu \text{m}\,\,\times 1200\,\,\mu \text{m}$
.