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A high linearity CMOS analog multiplier is designed and simulated. The input signal is preprocessed by active attenuator and the CMOS Gilbert multiplier is used for multiplication of the signal, and the bias circuit is designed meanwhile. When the supply voltage is ±1.8 V and the input range is ±0.6 V, the output range is less than ±25 mV and good linearity of the analog multiplier is obtained using optimized characteristics of transistors. The frequency doubling character of the analog multiplier is favorable since the -3 dB bandwidth of the analog multiplier is 181 MHz. Moreover, the temperature characteristic of multiplier is simulated and the layout of multiplier is designed optimally，and the relationship between linearity and output amplitude is discussed. The linearity of the multiplier during wider input range proposed herein is higher than that in the references.

Stem cell-related therapeutic technologies have garnered significant attention of the research community for their multi-faceted applications. To promote the therapeutic effects of stem cells, the strategies for cell microencapsulation in hydrogel microparticles have been widely explored, as the hydrogel microparticles have the potential to facilitate oxygen diffusion and nutrient transport alongside their ability to promote crucial cell-cell and cell-matrix interactions. Despite their significant promise, there is an acute shortage of automated, standardized, and reproducible platforms to further stem cell-related research. Microfluidics offers an intriguing platform to produce stem cell-laden hydrogel microparticles (SCHMs) owing to its ability to manipulate the fluids at the micrometer scale as well as precisely control the structure and composition of microparticles. In this review, the typical biomaterials and crosslinking methods for microfluidic encapsulation of stem cells as well as the progress in droplet-based microfluidics for the fabrication of SCHMs are outlined. Moreover, the important biomedical applications of SCHMs are highlighted, including regenerative medicine, tissue engineering, scale-up production of stem cells, and microenvironmental simulation for fundamental cell studies. Overall, microfluidics holds tremendous potential for enabling the production of diverse hydrogel microparticles and is worthy for various stem cell-related biomedical applications., (© 2024 Wiley‐VCH GmbH.)