Fully-Integrated, High-Efficiency, Multi-Output Charge Pump for High-Density Microstimulators

Rashidi, Amin; Yazdani, Niloofar; Sodagar, Amir M.

doi:10.1109/lsc.2018.8572121

Cited by 8 publications

(9 citation statements)

References 10 publications

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“…In the literature [10], a six-phase clock control scheme was proposed to control the crossed-coupled charge pump. In this proposed charge pump, adaption of the original work [10] was utilised and the four-phase clock scheme, shown in Fig.2(c) was used to control the Dickson charge pump converter Moreover, the charge pump design in [10] was designed to operate at 1.8 V input source, whereas this proposed design is for low-voltage solar harvested input source and thus the clock generators are able to work at ultra-low voltages.…”

Section: Challenge and Contribution 1: Eliminate Reverse Charge Sharimentioning

confidence: 99%

“…Challenge and Contribution 3: Two-step adiabatic CSC enable charge recycling as well as reduce power dissipation. Two-step adiabatic (CSC) high impedance capacitive driver was presented in [13,10]. Thanks to the tristate driver two-step charging-discharging was possible.…”

Section: Challenge and Contribution 2: Charge Recycling To Reduce Botmentioning

confidence: 99%

“…This produces CSC non-overlapped period signal (∆ ). According to [10], in contrary to one-step charging the energy dissipation from the source was reduce to three quarter (1)…”

Section: Challenge and Contribution 2: Charge Recycling To Reduce Botmentioning

confidence: 99%

“…Upon availability of native threshold transistor for both MOSFET pair in other technologies, the ultra-low input voltage of lower than 450mV can be configured. The proposed start-up design clock control scheme based on the literature [10] is implemented which was designed to prevent the any potential reverse charging for crossed-couple charge pump circuit and operates at 1.8V. The proposed design in Fig.3 uses standard transistors and general purpose transistors are appropriately used to ensure that the charge pump and the clock generators circuits are functional at low input voltage sources.…”

Section: B Proposed Control Scheme and Charge Pumpmentioning

confidence: 99%

See 3 more Smart Citations

Energy-Efficient Start-up Dickson Charge Pump for Batteryless Biomedical Implant Devices

Htet

Heidari

Moradi

et al. 2020

2020 27th IEEE International Conference on Electronics, Circuits and Systems (ICECS)

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This paper presents a power management concept for solar energy harvesting power management using an on-chip switched-capacitor (SC) DC-DC converter for biomedical implantable applications. This design eliminates potential reversion losses caused by the switching scheme. It also mitigates the bottom plate loss by employing the charge recycling technique. Moreover, instead of using a single step clock pulse, the two-step adiabatic charge sharing clock helps reduce the energy drawn from the PV cell by 65%. Furthermore, with the help of clock disabler scheme, the power dissipation has been further reduced by disabling the entire start-up charge pump once the desired reference output voltage was reached. However, due to additional circuitry for the clock disabler, there is a tradeoff between power efficiency and power dissipation. The proposed system was implemented and fabricated in a standard 0.18-μm TSMC RF CMOS technology. The proposed converter has achieved a maximum efficiency of 73%.

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Section: Challenge and Contribution 1: Eliminate Reverse Charge Sharimentioning

confidence: 99%

Section: Challenge and Contribution 2: Charge Recycling To Reduce Botmentioning

confidence: 99%

“…This produces CSC non-overlapped period signal (∆ ). According to [10], in contrary to one-step charging the energy dissipation from the source was reduce to three quarter (1)…”

Section: Challenge and Contribution 2: Charge Recycling To Reduce Botmentioning

confidence: 99%

Section: B Proposed Control Scheme and Charge Pumpmentioning

confidence: 99%

See 2 more Smart Citations

Energy-Efficient Start-up Dickson Charge Pump for Batteryless Biomedical Implant Devices

Htet

Heidari

Moradi

et al. 2020

2020 27th IEEE International Conference on Electronics, Circuits and Systems (ICECS)

View full text Add to dashboard Cite

show abstract

“…The start-up charge pump [15] or use 2-PV cells in series to boost the low voltage from the solar output 0.9 V input of the main charge pump. The 4-phases rotations series-parallel charge pump has implemented as the main circuit and presented in [16,17].…”

Section: Power Management In Subcutaneous Applicationsmentioning

confidence: 99%

Modelling of Implantable Photovoltaic Cells Based on Human Skin Types

Zhao

Htet

Ghannam

et al. 2019

2019 15th Conference on Ph.D Research in Microelectronics and Electronics (PRIME)

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Implantable electronic devices are emerging as important healthcare technologies due to their sustainable operation and low risk of infection. To overcome the drawbacks of the built-in battery in implantable devices, energy harvesting from the human body or another external source is required.. Energy harvesting using appropriately sized and properly designed photovoltaic cells enable implantable medical devices to be autonomous and self-powered. Among the challenges in using PV cells is the small fraction of incident light that penetrates the skin. Thus, it is necessary to involve such physical properties in the energy harvesting system design. Consequently, we propose a novel photodiode model that considers skin loss in different ethnic groups. Our physical simulations have been implemented using COMSOL and MATLAB. Circuit and system modelling has been performed using Cadence 180nm technology. Our results show that the transmittance of near infrared light is almost the same in three skin types: Caucasian, Asian and African. Maximum power delivery of 12 µW (African skin) and 14 µW (Caucasian and Asian skin) were achieved at 0.45 V. With the help of a power management unit, an output voltage of 1.8-2 V was achieved using the PV cells.

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Fully implantable, multi‐channel microstimulator with tracking supply ribbon, multi‐output charge pump and energy recovery

Rashidi

Yazdani

Sodagar

2020

IET Circuits, Devices & Syst

Self Cite

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A novel energy‐efficient approach dedicated to high‐density implantable stimulators such as visual prostheses is presented. Energy efficiency of the approach proposed in this work is achieved through two ideas: the ‘tracking supply ribbon’ technique and ‘reverse charge pumping’. The proposed approach is implemented, in the multi‐channel case, in such a way that power efficiency of each stimulation channel is enhanced according to its specific voltage/current condition and independently from other channels. For this purpose, a multi‐channel power‐efficient charge pump circuit with small integrated capacitors is proposed. Based on the proposed approach, a fully integrated 16‐channel stimulation backend for a visual prosthesis was designed and simulated in the transistor level in a standard 0.18‐μm triple‐well CMOS technology, occupying 1.41 mm2 of silicon area. According to post‐layout simulation results, power savings of up to 74% for a single channel and 81.5% for multiple channels are achieved compared to the conventional output stage with a constant supply voltage. Designed for the proposed stimulation backend, the charge pump generates output voltages of 3.48 V, −1.69 V, −3.38 V, and −5.05 V out of a 1.8 V input voltage and exhibits average power efficiency of 92.8% and 86.8% for one‐ and three‐stage circuits, respectively, all in the case of a 100 μA current load. All the aforementioned results are based on post‐layout simulation. Moreover, a proof‐of‐concept prototype was developed using off‐the‐shelf components in order to demonstrate the operation of the proposed tracking supply ribbon idea.

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Fully-Integrated, High-Efficiency, Multi-Output Charge Pump for High-Density Microstimulators

Cited by 8 publications

References 10 publications

Energy-Efficient Start-up Dickson Charge Pump for Batteryless Biomedical Implant Devices

Energy-Efficient Start-up Dickson Charge Pump for Batteryless Biomedical Implant Devices

Modelling of Implantable Photovoltaic Cells Based on Human Skin Types

Fully implantable, multi‐channel microstimulator with tracking supply ribbon, multi‐output charge pump and energy recovery

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