In this paper we present a programmable intraocular pressure sensor system implant integrated on a single CMOS chip. It contains on-chip micromechanical pressure sensor array, a temperature sensor, readout and calibration electronics, a µC-based digital control unit, and an RF-transponder. The transponder enables wireless data transmission and wireless power reception, thus making batteryless operation feasible. The chip has been fabricated in a 1.2 µm n-well CMOS process complemented by additional processing steps

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This work describes the architecture and realization of microelectronic components for a retina implant system that will provide visual sensations to patients with photoreceptor degeneration by applying electrostimulation of the intact retinal ganglion cell layer. Special circuitry has been developed for a fast single-chip CMOS image sensor system which provides high dynamic range of more than seven decades (without mechanical shutter) corresponding to the performance of the human eye. This image sensor system is directly attachable to a digital filter and a signal processor that compute the so-called receptive-field function for generation of the stimulation data. These external components are wireless linked to an implanted flexible silicon multielectrode stimulator which generates electrical signals for electrostimulation of the intact ganglion cells. All components, including additional hardware for digital signal processing and wireless data and power transmission have been developed for fabrication using our in-house standard CMOStechnology.

The operating range of passive UHF transponder systems is largely determined by the tag current consumption and the rectifier efficiency. Reading ranges of several meters have been reported for many state of the art RFID (Radio frequency IDentification) tags [1]. At this distance, the main issue for the recitier design is the low amplitude of the high frequency antenna signal. Schottky diodes are often used for their low forward voltage drop and high switching speed. As an alternative to Schottky diodes, different circuit techniques for compensation the threshold voltage of standard transistor diodes have been utilized [4]. The transistor gates are biased near the threshold voltage, so that the devices effectively act as diodes with very low forward voltage drop. In the presented rectifier, a secondary diode charge pump is used to generate the DC bias for the threshold voltage compensation. The circuit is implemented in a standard CMOS technology and operates at a minimum available power of -11.3 dBm for an output DC power of 7.5 µW

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Two micro implantable visual prosthesis systems for blind patients will be described. The first system is a retina implant which is based on an implantable microelectrostimulator applicable for patients suffering from retinitis pigmentosa or macula degeneration, and has been already successfully tested in animal experiments. The second system is an intraocular vision aid based on an implantable intraocular optoelectronic display encapsulated into a silicone diaphragm, which is applicable for patients suffering from bilateral corneal opacification but with intact posterior ocular segment. Both systems employ wireless power and data transmission using an 13 MHz RF-link for power transmission and either ASK modulation of the RF-carrier or a near IR optical link for data transmission from an external image acquisition and telemetry unit to both implantable micro devices

Abstract. In this paper a common-gate LNA is presented, which is used in a low-power IEEE 802.15.4 receiver with severer requirements on the current consumption. The LNA is designed in a 0.25 μm CMOS technology and consumes only 831 μA. The LNA achieves a voltage gain of 12.89 dB, a NF of 4.86 dB, and an IIP3 of −6.0 dBm.