This article presents an ultra-low-noise differential relaxation oscillator that achieves a phase noise figure of merits (FoMs) of 157.7 and 162.1 dBc/Hz, respectively, at 1- and 100-kHz frequency offsets. The oscillator is inherently robust against 1/f noise, while swing-boosting minimizes the phase noise arising out of thermal noise. Furthermore, an inverter-based differential comparator maximizes power efficiency, enabling FoMs close to the fundamental limits. Operating at 10.5 MHz and consuming 219.8 μW from a 1.4-V supply, the oscillator achieves a period jitter of 9.86 psrms, equivalent to a relative jitter of 0.01%. The oscillator occupies an active area of 0.015 mm² in a 0.18-μm standard CMOS process.

A broadband process, voltage, and temperature (PVT)-insensitive noise-canceling balun-low-noise amplifier (LNA) was implemented in the 0.13-μm CMOS process for subgigahertz wireless communication applications. The proposed LNA is based on the traditional common-gate common-source (CGCS) balun-LNA topology, and it adopts the diode-connected loads to reduce the noise contribution originated from CGCS transistors and enhance the linearity due to post linearization. The auxiliary common-source (CS) amplifier with a diode-connected is added to reduce the overall noise figure (NF) of the LNA by sharing an input signal with CGCS transistors and applying its output signal to the diode-connected load of CS transistor. Because the voltage gain of the LNA is determined by the transconductance (gₘ) ratio of the same types of nMOS transistors, its power gain (S₂₁) and NF are quite roust over PVT variations. In experiments, it showed S₂₁ of 14 dB and NF of 4 dB with an input return loss (S₁₁) of greater than 10 dB at 450 MHz. Concerning voltage variation (1.08-1.32 V) and temperature variation (-20 °C ~ +80 °C), the worst variations in S₂₁ and NF were approximately 1.4 and 1.1 dB, respectively.

Deep brain stimulation (DBS) refers to a neurosurgical process in which electrical stimulation is delivered via electrodes implanted within deep brain regions. DBS has become the most established clinical therapy for patients with movement disorders, although recent studies have investigated its application in a broad range of neurological and psychiatric disorders as well. Moreover, DBS has proven effective in controlling symptoms in patients with Parkinson’s disease (PD). While early DBS systems were capable of stimulation only, technological advancements have allowed for the direct assessment of dysfunctional brain activity and subsequent stimulation of the pathological circuitry. DBS can also be combined with neurochemical stimulation to address decreased concentrations of dopamine in the brain. Given that both electrical and neurochemical treatments for PD aim to rectify abnormalities in neural activity, the general term “neuromodulation” is considered more accurate and comprehensive. Recent improvements in signal detection and information processing techniques have provided further insight into PD mechanisms, which may aid in the development of personalized biomarkers and in the prediction of symptoms. In this comprehensive review, we discuss various aspects of neuromodulation in patients with PD, including basic theories, stimulation paradigms, and current challenges in the field.

This paper presents a 46 nF/10 $\text{M}\Omega $ -range, digital-intensive, reconfigurable RC-to-digital converter (R ² CDC) that can readout multiple C and R sensors in a time-interleaved fashion. Ratio-metric conversion using swing-boosted period-modulation (SB-PM) front-end by the R ² CDC results in 114 aF _rms / $0.37 \Omega _{\text {rms}}$ resolutions and a worst-case temperature-drift of 64.2 ppm/°C over −40 to 125°C. Femto-farad capacitances can be sensed with a relative code-deviation less than 0.16 % even when parasitics vary 30 times the baseline. Implemented in a $0.18 ~\mu \text{m}$ standard CMOS process, the R ² CDC consumes 140 $\mu \text{A}$ from a 1 V supply, occupying an active area of $0.175 ~\mu \text{m} ^{\mathrm{ 2}}$ .

This article presents a sub-ranging current reference with a low-temperature coefficient (TC) across a wide temperature range. By using a TC-adjustable current source and a process-insensitive sub-range detector, the impact of second-order TC can be reduced by nearly fourfold, without any discontinuities at the subrange boundaries. Implemented in a 0.18- $\mu$ m CMOS process, the proposed current reference achieves an average TC of 11.4-ppm/ $^{\circ}$ C across from $-$ 20 $^{\circ}$ C to 125 $^{\circ}$ C, obtained from 45 samples across five process corners without chip-by-chip calibration. The proposed current source exhibits low line and load sensitivities of 365 and 181 ppm/V, respectively, and an integrated noise of 38.9 pArms within a 10-Hz bandwidth.

Photothermal neuromodulation, a rapidly advancing technique in neuroscience, has been introduced as an incredibly versatile platform for the in‐depth study of neural electrophysiological signals and the development of treatments for various neurological disorders. Particularly, nanomaterial‐based photothermal neuromodulation technologies have advantages compared to optogenetic stimulation methods, such as non‐genetic modification, minimally invasive, and reduced immune response. Photothermal neuromodulation research has introduced various nanomaterials and stimulation methods to regulate thermosensitive ion channels or modify cell membrane capacitance, enabling excitation and inhibition of neural activity. Recent advances in nanomaterials have significantly improved the precision and efficiency of photothermal neuromodulation, expanding its potential applications in neuroscience research. In the photothermal neuromodulation studies, different temperature measurement methods have been used but do not satisfy all the requirements necessary to analyze this phenomenon. An ideal temperature sensor for a photothermal neuromodulation study must have high transparency, high thermal sensitivity, and high spatial and temporal resolution. This review aims to cover the current status of thermally induced neuromodulation studies and the transparent temperature sensing methodologies that can be used for photothermal neuromodulation.