Florian De Roose

15.2 A flexible ISO14443-A compliant 7.5mW 128b metal-oxide NFC barcode tag with direct clock division circuit from 13.56MHz carrier

Flexible low-cost RFID/NFC tags have great potential to be embedded in everyday objects providing them a unique identifier or sensor readout facilitating the Internet-of-Everything, whereby a smartphone or tablet is the interface to the Internet-of-Things. The main challenge for flexible metal-oxide RFID tags is to fully comply with the ISO14443-A NFC standard to enable readout by standard NFC reader or handheld devices, due to the limited charge carrier mobility of the semiconductor and multiple sources of parameter variation caused by roughness, temperature and dimensional stability of the foils. Recent work by various groups [1–4] demonstrated only an incremental improvement in data rates from 50b/s to 396.5kb/s to be compatible with ISO14443 (105.9kb/s). In this work, we present a flexible metal-oxide NFC chip that is compliant with ISO14443-A, showcasing advancements on memory size, power consumption and a clock generation circuit.

16.5 A flexible thin-film pixel array with a charge-to-current gain of 59µA/pC and 0.33% nonlinearity and a cost effective readout circuit for large-area X-ray imaging

We report an active, medical-grade, high resolution, high dynamic range X-ray backplane based on a-IGZO thin-film technology with fast readout. This enables low dose, video rate X-ray imaging. Fast X-ray imaging will find its applications not only in medical, but also in non-destructive inspection. Curved imagers will yield sharper images when illuminated from a point source. This has been achieved thanks to superior a-IGZO technology and a pixel topology that improves noise performance and allows a cost-effective external readout.

An active artificial iris controlled by a 25-μW flexible thin-film driver

We show an active artificial iris based on solely thin-film components, wherein several LCD elements are controlled a metal-oxide TFT and by powered by thin-film photovoltaics (TFPV). Key aspects for the driver are size and low power consumption. We demonstrate power consumption down to 25μW for the full iris.

Flexible selfbiased 66.7nJ/c.s. 6bit 26S/s successive-approximation C-2C ADC with offset cancellation using unipolar Metal-Oxide TFTs

Metal-Oxide thin-film transistors (TFTs) present unique opportunities to develop robust, low-cost and transparent electronics that can mechanically endure on flexible and stretchable substrates over large area in an industry compatible technology. Analog to digital converters (ADC) are an essential part of the Internet-of-Everything, where a multitude of sensing applications are envisaged, such as temperature and pressure sensor tags on human skin. In this work, dual-gate InGaZnO TFTs (IGZO) are demonstrated to achieve a 6-bit successive approximation (SAR) C-2C ADC operated at a clock of up to 400Hz and a power dissipation of 52.2µW at a power supply of Vdd=15V. The ADC achieves a differential nonlinearity (DNL) of 0.7LSB and an integral nonlinearity (INL) of 0.58 LSB using only n-type TFTs. A figure of merit (FoM) of 66.7nJ/c.s. is achieved from an ADC on flexible substrate.

Design of a frequency reference based on a PVT-independent transmission line delay

This paper proposes a novel integrated oscillator topology based on a transmission line. The frequency is extracted from the delay of the transmission line, which is intrinsically independent of temperature and supply variations. The architecture for the oscillator, guidelines for the design of the transmission line as well as the different building blocks are presented. The architecture is based on a phase-locked loop topology. The transmission line used has a 509 ps delay, an area of 2.26 mm2 and a 4.38 dB power loss. The effect of process variations on the transmission line is extensively investigated. A digital driver using CMOS inverters and an analog driver based on an OTA are proposed. Both have a good stability over temperature. The Gilbert cell is proposed as a detector at the output of the transmission line and the corresponding design considerations are shown. Closed loop simulations show fast locking, a variation of 8.3°C between -10°C and 85°C and a variation of 3.70/00 for Vdd ± 10%.