Browsing by Author "Yang, Tzu-Yi"

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A 1.2 V 114 mW Dual-Band Direct-Conversion DVB-H Tuner in 0.13 mu m CMOS
(2009-03-01)
Kuo, Ming-Ching
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Kao, Shiau-Wen
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Chen, Chih-Hung
;
Hung, Tsun-Shuen
;
Shih, Yi-Shing
A fully integrated direct-conversion tuner is implemented in 0.13 mu m CMOS technology. A broadband noise-canceling balun LNA with the proposed dual cross-coupling technique helps achieve an overall receiver noise figure from 3.7 to 4.3 dB while consuming only 3.6 mW. The proposed current-mode switching scheme improves the achievable SNIR with a gain step of 15 dB, providing IIP3 improvement of 18 dB and NF degradation of only 6 dB. Moreover, design trade-offs are carefully considered in designing the baseband circuit, which provides wide gain tuning and bandwidth accuracy with a DC offset residual less than 6 mV. The measured maximum SNR values are better than 30 dB over wide input power levels, ensuring robust reception in a mobile environment. All circuit blocks are operated at 1.2 V. As a result, the tuner consumes power as low as 114 mW in the continuous mode. This compact tuner supports both UHF and L-bands, and occupies only 7.2 mm(2) die area.
A 1.2V Interference-Sturdiness, DC-Offset Calibrated CMOS Receiver Utilizing a Current-Mode Filter for UWB
(2008)
Shih, Horng-Yuan
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Chen, Wei-Hsien
;
Juang, Kai-Chenug
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Yang, Tzu-Yi
;
Kuo, Chien-Nan
An interference-sturdiness receiver with a current-mode filter for 3-5GHz UWB applications is implemented in a 1.2V 0.13 mu m CMOS process. The chip provides a maximum voltage gain of 70dB and a dynamic range of 60dB. The measured in-band OIP3 is +9.39dBm, out-of-band IIP3 -15dBm and noise figure 6.8dB in the maximum gain mode. An algorithm for the automatic digital DC offset calibration is also demonstrated.
A 250 MHz 14 dB-NF 73 dB-Gain 82 dB-DR Analog Baseband Chain With Digital-Assisted DC-Offset Calibration for Ultra-Wideband
(2010-02-01)
Shih, Horng-Yuan
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Kuo, Chien-Nan
;
Chen, Wei-Hsien
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Yang, Tzu-Yi
;
Juang, Kai-Chenug
A 250 MHz analog baseband chain for Ultra-Wideband was implemented in a 1.2 V 0.13 mu m CMOS process. The chip has an active area of 0.8 mm(2). In the analog baseband, PGAs and filters are carried out by current-mode amplifiers to achieve wide bandwidth and wide dynamic range of gain, as well as low noise and high linearity. Besides, a current-mode Sallen-Key low-pass filter is adopted for effective rejection of out-of-band interferers. A 6th-order Chebyshev low-pass filter realized in G(m)-C topology is designed in the baseband chain for channel selection. Digitally-assisted DC-offset calibration improves second-order distortion of the entire chain. The design achieves a maximum gain of 73 dB and a dynamic range of 82 dB. Measured noise figure is 14 dB, an IIP3 of -6 dBV, and IIP2 of -5 dBV at the maximum gain mode. The analog baseband chain consumes 56.4 mA under supply of 1.2 V.
A Bone-Guided Cochlear Implant CMOS Microsystem Preserving Acoustic Hearing
(2017-01-01)
Qian, Xin-Hong
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Wu, Yi-Chung
;
Yang, Tzu-Yi
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Cheng, Cheng-Hsiang
;
Chu, Hsing-Chien
In this paper, a bone-guided cochlear implant (BGCI) SOC microsystem is proposed and designed. The BGCI microsystem uses four or more electrodes placed on the bone surface of the cochlea and one on the round window to preserve partially the acoustic hearing. The external SOC of the BGCI processes the acoustic signals and generates stimulation patterns and command that are transmitted to the implanted chip through the 13.56MHz wireless power and bidirectional data telemetry. The implanted chip with 4-channel high-voltage-tolerant stimulator generates biphasic stimulation currents up to 800 mu A and sends back the power indication and electrode impedance error signals to the external SOC. Electrical tests on the fabricated BGCI has been performed. The in-vivo animal tests on guinea pigs has shown the evoked Wave III of EABR waveforms. The proposed BGCI can be applied to patients with high-frequency hearing loss, tinnitus, and dizziness.
A Digitally Dynamic Power Supply Technique for 16-Channel 12 V-Tolerant Stimulator Realized in a 0.18-mu m 1.8-V/3.3-V Low-Voltage CMOS Process
(2017-10-01)
Luo, Zhicong
;
Ker, Ming-Dou
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Yang, Tzu-Yi
;
Cheng, Wan-Hsueh
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電子工程學系及電子研究所
A new digitally dynamic power supply technique for 16-channel 12-V-tolerant stimulator is proposed and realized in a 0.18-mu m 1.8-V/3.3-V CMOS process. The proposed stimulator uses four stacked transistors as the pull-down switch and pullup switch to withstand 4 times the nominal supply voltage (4 x VDD). With the dc input voltage of 3.3 V, the regulated threestage charge pump, which is capable of providing 11.3-V voltage at 3-mA loading current, achieves dc conversion efficiency of up to 69% with 400-pF integrated capacitance. Power consumption is reduced by implementing the regulated charge pump to provide a dynamic dc output voltage with a 0.5-V step. The proposed digitally dynamic power supply technique, which is implemented by using a p-type metal oxide semiconductor (PMOS) inverter with pulldown current source and digital controller, greatly improves the power efficiency of a system. The silicon area of the stimulator is approximately 3.5 mm(2) for a 16-channel implementation. The functionalities of the proposed stimulator have been successfully verified through animal test.
A Fully Integrated 16-Channel Closed-Loop Neural-Prosthetic CMOS SoC With Wireless Power and Bidirectional Data Telemetry for Real-Time Efficient Human Epileptic Seizure Control
(2018-11-01)
Cheng, Cheng-Hsiang
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Tsai, Ping-Yuan
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Yang, Tzu-Yi
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Cheng, Wan-Hsueh
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Yen, Ting-Yang
A 16-channel closed-loop neuromodulation system-on-chip (SoC) for human epileptic seizure control is proposed and designed. In the proposed SoC, a 16-channel neural-signal acquisition unit (NSAU), a biosignal processor (BSP), a 16-channel high-voltage-tolerant stimulator (HVTS), and wireless power and bidirectional data telemetry are designed. In the NSAU, the input protection circuit is used to prevent MOSFET from overstressing by the high-voltage stimulations. Hence, NSAUs can share electrodes with stimulators. The auto-reset chopper-stabilized capacitive-coupled instrumentation amplifiers (AR-CSCCIAs) are designed with the chopper-stabilized technique with a new offset reduction loop. The measured input-referred noise is 2.09 mu V-rms and the noise-efficiency factor (NEF) is 3.78. The entropy-and-spectrum seizure detection algorithm is implemented in the BSP with 0.76-s seizure detection latency and 97.8% detection accuracy. When the seizure onset is detected by the BSP, the HVTS with adaptive supply control delivers 0.5-3-mA biphasic current stimulation to suppress the seizure onset. The proposed SoC is powered wirelessly, and the bidirectional data telemetry is realized through the same pair of coils in 13.56 MHz. The downlink data rate is 211 Kb/s with the binary phase-shift keying (BPSK) modulation and a new BPSK demodulator. The uplink data rate is 106 Kb/s with the load-shift keying (LSK) modulation. The proposed SoC is fabricated in a 0.18-mu m CMOS technology and occupies 25 mm(2). Electrical tests have been performed to characterize the SoC performance. In vivo animal experiments using mini-pigs have been performed to successfully verify the closed-loop neuromodulation functions on epileptic seizure suppression.
A Fully Integrated Closed-Loop Neuromodulation SoC with Wireless Power and Bidirectional Data Telemetry for Real-Time Human Epileptic Seizure Control
(2017-01-01)
Cheng, Cheng-Hsiang
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Tsai, Ping-Yuan
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Yang, Tzu-Yi
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Cheng, Wan-Hsueh
;
Yen, Ting-Yang
This paper presents a 16-channel closed-loop neuromodulation SoC for human seizure control. The SoC includes a 16-ch signal acquisition unit, a bio-signal processor, a 16-ch adaptive stimulator, and wireless telemetry. The signal acquisition unit achieves 3.78 NEF and shares electrodes with stimulator. The seizure detection latency is 0.76s and delivered 0.5-3mA biphasic current stimulation. The SoC is powered wirelessly and bidirectional data telemetry is realized through the same pair of coils in 13.56MHz.
A Q-band Direct Divide-by-4 Injection-Locked Frequency Divider with Quadrature Outputs
(2010-01-01)
Yan, Tzu-Chao
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Shih, Horng-Yuan
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Yang, Tzu-Yi
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Kuo, Chien-Nan
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交大名義發表
A divide-by-4 injection-locked frequency divider is designed for applications in the millimeter-wave frequency range. The proposed circuit also features in quadrature phase outputs by using a quadrature voltage-controlled oscillator. The input signal is injected into the common-mode node at the tail current source directly. Implemented in a 0.13 mu m CMOS technology, the core circuit consumes dc power of 3.66mW with 1.2 V supply voltage. The operation range achieves 1.95 GHz. The entire die occupies an area of 974x726 um(2).
An Ultra-Low Power Interface CMOS IC Design for Biosensor Applications
(2012)
Hu, Weibo
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Liu, Yen-Ting
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Das, Vighnesh
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Schecht, Cliff
;
Tam Nguyen
This paper presents a design example of an ultra-low power single-channel analog front-end (AFE) integrated circuits (IC) and system for biomedical sensing applications. The 0.18-mu m CMOS AFE IC design includes a low noise instrumentation amplifier (INA), a low-pass filter (LPF), a variable gain amplifier (VGA), and a successive approximation register (SAR) analog-to-digital converter (ADC). The AFE IC architecture is analyzed on the system level to minimize total power consumption with high integration and optimized for an ECG sensing system. SPICE simulations of the AFE IC channel validate the ultra-low power IC design methodology for heartbeat detection with less than 1 mu A/channel.
Design and In Vivo Verification of a CMOS Bone-Guided Cochlear Implant Microsystem
(2019-11-01)
Qian, Xin-Hong
;
Wu, Yi-Chung
;
Yang, Tzu-Yi
;
Cheng, Cheng-Hsiang
;
Chu, Hsing-Chien
Objective: To develop and verify a CMOS bone-guided cochlear implant (BGCI) microsystem with electrodes placed on the bone surface of the cochlea and the outside of round window for treating high-frequency hearing loss. Methods: The BGCI microsystem consists of an external unit and an implanted unit. The external system-on-chip is designed to process acoustic signals through an acquisition circuit and an acoustic DSP processor to generate stimulation patterns and commands that are transmitted to the implanted unit through a 13.56 MHz wireless power and bidirectional data telemetry. In the wireless power telemetry, a voltage doubler/tripler (2X/3X) active rectifier is used to enhance the power conversion efficiency and generate 2 and 3 V output voltages. In the wireless data telemetry, phase-locked loop based binary phase-shift keying and load-shift keying modulators/demodulators are adopted for the downlink and uplink data through high-Q coils, respectively. The implanted chip with four-channel high-voltage-tolerant stimulator generates biphasic stimulation currents up to 800 mu A. Results: Electrical tests on the fabricated BGCI microsystem have been performed to verify the chip functions. The in vivo animal tests in guinea pigs have shown the evoked third wave of electrically evoked auditory brainstem response waveforms. It is verified that auditory nerves can be successfully stimulated and acoustic hearing can be partially preserved. Conclusion and Significance: Different from traditional cochlear implants, the proposed BGCI microsystem is less invasive, preserves partially acoustic hearing, and provides an effective alternative for treating high-frequency hearing loss.
Enhanced Photocarrier Generation with Selectable Wavelengths by M-Decorated-CuInS2 Nanocrystals (M = Au and Pt) Synthesized in a Single Surfactant Process on MoS2 Bilayers
(2019-02-22)
Tang, Shin-Yi
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Medina, Henry
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Yen, Yu-Ting
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Chen, Chia-Wei
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Yang, Tzu-Yi
A facile approach for the synthesis of Au- and Pt-decorated CuInS2 nanocrystals (CIS NCs) as sensitizer materials on the top of MoS2 bilayers is demonstrated. A single surfactant (oleylamine) is used to prepare such heterostructured noble metal decorated CIS NCs from the pristine CIS. Such a feasible way to synthesize heterostructured noble metal decorated CIS NCs from the single surfactant can stimulate the development of the functionalized heterostructured NCs in large scale for practical applications such as solar cells and photodetectors. Photodetectors based on MoS2 bilayers with the synthesized nanocrystals display enhanced photocurrent, almost 20-40 times higher responsivity and the On/Off ratio is enlarged one order of magnitude compared with the pristine MoS2 bilayers-based photodetectors. Remarkably, by using Pt- or Au-decorated CIS NCs, the photocurrent enhancement of MoS2 photodetectors can be tuned between blue (405 nm) to green (532 nm). The strategy described here acts as a perspective to significantly improve the performance of MoS2-based photodetectors with the controllable absorption wavelengths in the visible light range, showing the feasibility of the possible color detection.
New Simultaneous Exfoliation and Doping Process for Generating MX2 Nanosheets for Electrocatalytic Hydrogen Evolution Reaction
(2019-04-24)
Van-Truong Nguyen
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Yang, Tzu-Yi
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Phuoc Anh Le
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Yen, Po-Jen
;
Chueh, Yu-Lun
Doping nonmetal atoms into layered transition metal dichalcogenide MX2 structures has emerged as a promising strategy for enhancing their catalytic activities for the hydrogen evolution reaction. In this study, we developed a new and efficient one-step approach that involves simultaneous plasma-induced doping and exfoliating of MX2 bulk into nanosheets-such as MoSe2, WSe2, MoS2, and WS2 nano sheets-within a short time and at a low temperature (ca. 80 degrees C). Specifically, by utilizing active plasma that is generated with an asymmetric electrical field during the electrochemical reaction at the surface of the submerged cathode tip, we are able to achieve doping of nitrogen atoms, from the electrolytes, into the semiconducting 2H-MX2 structures during their exfoliation process from the bulk states, forming N-doped MX2. We selected N-doped MoS2 nanosheets for demonstrating their catalytic hydrogen evolution potential. We modulated the electronic and transport properties of the MoS2 structure with the synergy of nitrogen doping and exfoliating for enhancing their catalytic activity. We found that the nitrogen concentration of 5.2 atom % at N-doped MoS2 nanosheets have an excellent catalytic hydrogen evolution reaction, where a low overpotential of 164 mV at a current density of 10 mA cm(-2) and a small Tafel slope of 71 dec mV(-1)-much lower than those of exfoliated MoS2 nanosheets (207 mV, 82 dec mV(-1)) and bulk MoS2 (602 mV, 198 dec mV(-1))-as well as an extraordinary long-term stability of >25 h in 0.5 M H2SO4 can be achieved.