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In near-field electromagnetic links, the inductive voltage is usually much larger than the compliance of low-voltage integrated-circuit (IC) technologies used for the implementation of implantable devices. Thus most integrated power-recovery approaches limit the induced signal to low voltages with inefficient shunt regulation or voltage clipping. In this paper, we propose using high-voltage (HV) complementary metal-oxide semiconductor technology to fully integrate the inductive power and data-recovery front end while adopting a step-down approach where the inductive voltage is left free up to 20 or 50 V. The advantage is that excessive inductive power will translate to an additional charge that can be stored in a capacitor, instead of shunting to ground excessive current with voltage limiters. We report the design of two consecutive HV custom ICs-IC1 and IC2-fabricated in DALSA semiconductor C08G and C08E technologies, respectively, with a total silicon area (including pads) of 4 and 9 mm(2), respectively. Both ICs include HV rectification and regulation; however, IC2 includes two enhanced rectifier designs, a voltage-doubler, and a bridge rectifier, as well as data recovery. Postlayout simulations show that both IC2 rectifiers achieve more than 90% power efficiency at a 1-mA load and provide enough room for 12-V regulation at a 3-mA load and a maximum-available inductive power of 50 mW only. Successful measurement results show that HV regulators provide a stable 3.3- to 12-V supply from an unregulated input up to 50 or 20 V for IC1 and IC2, respectively, with performance that matches simulation results.

In order to investigate new neurostimulation strategies for micturition recovery in spinal cord injured patients, custom implantable stimulators are required to carry-on chronic animal experiments. However, higher integration of the neurostimulator becomes increasingly necessary for miniaturization purposes, power consumption reduction, and for increasing the number of stimulation channels. As a first step towards total integration, we present in this paper the design of a highly-integrated neurostimulator that can be assembled on a 21-mm diameter printed circuit board. The prototype is based on three custom integrated circuits fabricated in High-Voltage (HV) CMOS technology, and a low-power small-scale commercially available FPGA. Using a step-down approach where the inductive voltage is left free up to 20 V, the inductive power and data recovery front-end is fully integrated. In particular, the front-end includes a bridge rectifier, a 20-V voltage limiter, an adjustable series regulator (5 to 12 V), a switched-capacitor step-down DC/DC converter (1:3, 1:2, or 2:3 ratio), as well as data recovery. Measurements show that the DC/DC converter achieves more than 86% power efficiency while providing around 3.9-V from a 12-V input at 1-mA load, 1:3 conversion ratio, and 50-kHz switching frequency. With such efficiency, the proposed step-down inductive power recovery topology is more advantageous than its conventional step-up counterpart. Experimental results confirm good overall functionality of the system.

A single-chip wide-band tuner with an active splitter for cable data modems and set-top boxes is realized in a 0.5µm, 30GHz BiCMOS technology [1]. The IC employs a single down-conversion, low-IF architecture and can receive signals in the 48-860MHz frequency range. Fully integrated selectivity is obtained in combination with a channel decoder. Power consumption is 1.5W with a 3.3V supply.Existing dual-conversion architectures like [2-4], remove the need for tuner alignment, but still use external fixed frequency filters. The goal of this work is to fully integrate the TV front-end selectivity and make external RF and filter components (like coils, SAW and ceramic filters) obsolete, without compromising performance.The IC (Fig. 25.3.1) contains a splitter amplifier, RF AGC amplifier, switchable RF band-pass filter, RF polyphase filter, double quadrature down-conversion mixer, IF polyphase filter, groupdelay correction filter, low-pass filter, IF AGC amplifier, fully integrated voltage controlled oscillator (VCO), synthesizer and a received signal strength indication (RSSI) circuit.

This paper concerns the design and implementation of a new implantable Neuro-Monito-Stimulation System (NMSS) for the urinary tract rehabilitation in paraplegics. In addition to selective stimulation for voluntary micturition and permanent stimulation for reduction of the detrusor overactivity, the NMSS includes telemetry capabilities of electrodes-tissues contact. Resistance up to 10kΩ could be measured with good linearity and sent wirelessly to an external controller at 1 kbps data transmission rate. With an embedded rechargeable battery, the implant lifetime is significantly extended up to 1000 cycles of 250 hours with nominal operating conditions. The NMSS design is described with the main system solutions and the preliminary experimental results.