Timothy G. Constandinou

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This paper describes a platform to achieve targeted drug delivery in the next-generation wireless capsule endoscopy. The platform consists of two highly novel subsystems: one is a micropositioning mechanism which can deliver 1 ml of targeted medication and the other is a holding mechanism, which gives the functionality of resisting peristalsis. The(More)
BACKGROUND Extracellular recordings are performed by inserting electrodes in the brain, relaying the signals to external power-demanding devices, where spikes are detected and sorted in order to identify the firing activity of different putative neurons. A main caveat of these recordings is the necessity of wires passing through the scalp and skin in order(More)
—This paper describes a novel partial-current-steering stimulation drive for implantable neural prosthetics. The drive hardware momentarily delivers a charge-balanced asymmetric stimulus to a dummy load before steering towards the stimulation electrodes. In this fashion, power is conserved whilst still gaining from the benefits of current steering. The(More)
Vdd Vdd Vdd A floating-gate pseudo-differential transconductor is presented, in which the differential input signal is allowed to have a dc offset. Normally such an offset would render a normal CMOS differential pair useless. The circuit "VX v y " inherently removes any dc offset from the floating gates lout(-) lO"I(+) by feedback mechanisms involving(More)
Neuromodulation has wide ranging potential applications in replacing impaired neural function (prosthetics), as a novel form of medical treatment (therapy), and as a tool for investigating neurons and neural function (research). Voltage and current controlled electrical neural stimulation (ENS) are methods that have already been widely applied in both(More)
This paper describes a novel partial-current-steering stimulation circuit for implantable vestibular prostheses. The drive hardware momentarily delivers a charge-balanced asymmetric stimulus to a dummy load before steering towards the stimulation electrodes. In this fashion, power is conserved while still gaining from the benefits of current steering. The(More)
Next generation neural interfaces aspire to achieve real-time multi-channel systems by integrating spike sorting on chip to overcome limitations in communication channel capacity. The feasibility of this approach relies on developing highly efficient algorithms for feature extraction and clustering with the potential of low-power hardware implementation. We(More)
This paper presents an 8 channel energy-efficient neural stimulator for generating charge-balanced asymmetric pulses. Power consumption is reduced by implementing a fully-integrated DC-DC converter that uses a reconfigurable switched capacitor topology to provide 4 output voltages for Dynamic Voltage Scaling (DVS). DC conversion efficiencies of up to 82%(More)
In this work we present an adaptable foveating vision biological eye has exceptionally good optomechanics. This chip. This chip has no physical foveation; all its pixels are in the enables the eye to be moved round the visual field at high speeds. same uniform pattern. However with a given input signal it is In contrast, even with modem MEMS technologies,(More)