A 0.33 nJ/bit IEEE802.15.6/Proprietary MICS/ISM Wireless Transceiver With Scalable Data Rate for Medical Implantable Applications

Abstract

This paper presents an ultra-low power wireless transceiver specialized for but not limited to medical implantable applications. It operates at the 402-405-MHz medical implant communication service band, and also supports the 420-450-MHz industrial, scientific, and medical band. Being IEEE 802.15.6 standard compliant with additional proprietary modes, this highly configurable transceiver achieves date rates from 11 kb/s to 4.5 Mb/s, which covers the requirements of conventional implantable applications. The phase-locked loop-based transmitter architecture is adopted to support various modulation schemes with limited power budget. The zero-IF receiver has programmable gain and bandwidth to accommodate different operation modes. Fabricated in 40-nm CMOS technology with 1-V supply, this transceiver only consumes 1.78 mW for transmission and 1.49 mW for reception. The ultra-low power consumption together with the 15.6-compliant performance in term of modulation accuracy, sensitivity, and interference robustness make this transceiver competent for various implantable applications.

A 0.55 V Bandgap Reference with a 59 ppm/°C Temperature Coefficient

“…Equation (1) reveals that it has a negative temperature coefficient due to the temperature dependency of IS, hence this acts as CTAT. If two BJTs operate at different current densities, the difference of their VBE's presents an excellent PTAT, which can be expressed as follows:…”

“…Another challenge in the design of these analog precision circuits for bio-medical transceivers is the low power supply requirement (<0.6V), since they are often implemented in deep submicron CMOS technology nodes to enable them with digital signal processing capabilities. [1] Since the first BJT-based bandgap reference design was introduced [2], it has been improved continuously in many aspects to minimize the power dissipation, reduce the operating voltage and improving robustness against startup issues. The current trend however is to design the BGR with pure CMOS, without the need of any parasitic prone BJTs.…”

Active implantable sensor powered by ultrasounds with application in the monitoring of physiological parameters for soft tissues

“…Energy sources available for sensors deployed inside a physiological environment include electrochemical [4], photovoltaic [5], thermoelectric [6], mechanical [7], magnetic (inductive) [8], electromagnetic (RF) [9] and ultrasounds [10]. The efficiency in conversion to readily in-use electrical energy dictates that, for the time being, only inductive near-field, far-field RF and ultrasounds have the potential to fulfil the power requirements of the embedded electronics in the sensor.…”

“…The constrains in the physical dimension and location of these devices, together with the power consumption requirements, all settle the framework for achieving the acceptable level of operation of the implant without causing side effects [12]. The complexity of the electronics to correctly sense, process and transmit the data has a direct impact on power consumption which, in turn, increases the physical volume for energy conversion and storage [9]. Batteries impose a life-term to the implant (10 years at best) and a surgical intervention for replacement.…”

Simultaneous Energy and Data Wireless Transfer Attenuation in Biological Channel of Deep Implantable Medical Devices: Characteristic Analysis and Modeling

“…), Medical Implant Communication Services (MICS) criterion (402-405 MHz), and ultra-wideband (UWB) (3.1-10.6 GHz) [7][8][9][10][11]. The goal of this work is to choose an appropriate transmission carrier frequency for synchronous wireless transmission of energy and data for deep implantable medical devices, and based on this frequency, to then carry out attenuation characteristic analysis and mathematical modeling.…”