A ±4A high-side current sensor with 25V input CM range and 0.9% gain error from -40°C to 85°C using an analog temperature compensation technique

This paper presents a fully integrated ±4A current sensor that supports a 25V input common-mode voltage range (CMVR) while operating from a single 1.5V supply. It consists of an on-chip metal shunt, a beyond-the-rails ADC [1] and a temperature-dependent voltage reference. The beyond-the-rails ADC facilitates high-side current sensing without the need for external resistive dividers or level shifters, thus reducing power consumption and system complexity. To compensate for the shunt's temperature dependence, the ADC employs a proportional-to-absolute-temperature (PTAT) reference voltage. Compared to digital temperature compensation schemes [2,3], this analog scheme eliminates the need for a temperature sensor, a band-gap voltage reference and calibration logic. As a result, the current sensor draws only 10.9μA and is 10x more energy efficient than [2]. Over a ±4A range, and after a one-point trim, the sensor exhibits a 0.9% (max) gain error from -40°C to 85°C and a 0.05% gain error at room temperature. The former is comparable with that of other fully-integrated current sensors [2-4], while the latter represents the state-of-the-art.</p

An oversampled 12/14b SAR ADC with noise reduction and linearity enhancements achieving up to 79.1dB SNDR

Autonomous wireless sensor nodes for cloud networks require ultra-low-power electronics. In particular, sensor readout interfaces need low-speed high-precision ADCs for capturing, e.g., bio-potential signals, environmental information, or interactive multimedia. For these applications, state-of-the-art SAR ADCs can provide highly power-efficient solutions

A 480mW 2.6GS/s 10b 65nm CMOS time-interleaved ADC with 48.5dB SNDR up to Nyquist

Trends in cable TV reception for data and video require simultaneous capture of many channels, e.g., 16, arbitrary located in the 48-to-1002MHz TV band. The challenges of integrating more than two zero-IF tuners on a single die could be simplified with a low-power 10b ADC that can digitize the entire TV band and be suitable for integration with baseband DSP. This work presents a 64¿ inter leaved 2.6GS/S 10b 65nm CMOS ADC with on-chip calibrations, combining interleaving hierarchy with an open-loop buffer array operated in feedforward sampling and feedback-SAR mode. The ADC achieves an SNDR of 48.5dB at Nyquist and consumes only 0.48W

A 480mW 2.6GS/s 10b 65nm CMOS time-interleaved ADC with 48.5dB SNDR up to Nyquist

Trends in cable TV reception for data and video require simultaneous capture of many channels, e.g., 16, arbitrary located in the 48-to-1002MHz TV band. The challenges of integrating more than two zero-IF tuners on a single die could be simplified with a low-power 10b ADC that can digitize the entire TV band and be suitable for integration with baseband DSP. This work presents a 64¿ inter leaved 2.6GS/S 10b 65nm CMOS ADC with on-chip calibrations, combining interleaving hierarchy with an open-loop buffer array operated in feedforward sampling and feedback-SAR mode. The ADC achieves an SNDR of 48.5dB at Nyquist and consumes only 0.48W

A phase-domain readout circuit for a CMOS-compatible thermal-conductivity-based carbon dioxide sensor

The measurement of carbon-dioxide (CO2) concentration is very important in home and building automation, e.g. to control ventilation in energy-efficient buildings. This application requires compact, low-cost sensors that can measure CO2 concentration with a resolution of &lt;200 ppm over a 2500ppm range. Conventional optical (NDIR-based) CO2 sensors require components that are CMOS-incompatible, difficult to miniaturize and power-hungry [1]. Due to their CMOS compatibility, thermal-conductivity-based sensors are an attractive alternative [2,3]. They exploit the fact that the thermal conductivity (TC) of CO2 is lower than that of the other constituents of air, so that CO2 concentration can be indirectly measured via the heat loss of a hot wire to ambient. However, this approach requires the detection of very small changes in TC (0.25 ppm per ppm CO2 [3]).Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic InstrumentationMicroelectronic

A 680nA fully integrated implantable ECG-acquisition IC with analog feature extraction

Ultra-low power consumption and miniature size are by far the most important design requirements for implantable pacemakers. In order to guarantee a long life span of the device, saving power in the sensing IC is a primary concern as cardiac rhythm disorders must be continuously monitored [1]. Shifting the functionality of QRS-band power parameter extraction to the analog domain can reduce system-level power consumption of heartbeat detection significantly through minimizing computational complexity of the DSP [2,3]. In addition, current biomedical ICs still require further improvement of power efficiency as their analog back ends consume significant power [2-4]. For low-power means, the presented analog signal processor (ASP) introduces a power-efficient analog feature extraction, a current-multiplexed ADC driver and a flexible ADC. This advances the state of the art by reducing the power consumption of the ASP below 1µW without compromising other specs, such as input SNR &gt;70dB, CMRR &gt;90dB, PSRR &gt;80dB, and enables low-power heartbeat detection for implantable pacemakers

A 0.53pJK27000μm2resistor-based temperature sensor with an inaccuracy of ±0.35°C (3σ) in 65nm CMOS

In microprocessors and DRAMs, on-chip temperature sensors are essential components, ensuring reliability by monitoring thermal gradients and hot spots. Such sensors must be as small as possible, since multiple sensors are required for dense thermal monitoring. However, conventional BJT-based temperature sensors are not compatible with the sub-1V supply of advanced processes. Subthreshold MOSFETs can operate from lower supplies, but at high temperatures their performance is limited by leakage [1,2]. Thermal diffusivity (TD) sensors achieve sub-1V operation and small area with moderate accuracy, but require milliwatts of power [3]. Recently, resistor-based sensors based on RC WienBridge (WB) filters have realized high resolution and energy efficiency [4,5]. Fundamentally, they are robust to process and supply-voltage scaling. However, their readout circuitry has been based on continuous-time (CT) ΔΣ ADCs or frequency-locked loops (FLLs), which require precision analog circuits and occupy considerable area (&gt;0.7mm 2 ).Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Microelectronic

A 0.33nJ/b IEEE802.15.6/proprietary-MICS/ISM-band transceiver with scalable data-rate from 11kb/s to 4.5Mb/s for medical applications

The introduction of the IEEE802.15.6 standard (15.6) for wireless-body-area networks signals the advent of new medical applications, where various wireless nodes in, on or around a human body monitor vital signs. Radio communication often dominates the power consumption in the nodes, thus low-power transceivers are desired. Most state-of-the-art low-power transceivers support only proprietary modes with OOK or FSK modulations, and have poor sensitivity or low data rate [1,2]. In this work, a 15.6-compliant transceiver with enhanced performance is proposed. First, the data-rate is extended to 4.5Mb/s to cover multi-channel EEG applications. Second, while a best-in-class energy efficiency of 0.33nJ/b is achieved in the high-speed mode, a dedicated low-power mode reduces the RX power further in low-data-rate operation. Third, a sensitivity 5 to 10dB better than the 15.6 specification is targeted to accommodate extra path loss due to shadowing effects from human bodies

A 0.33nJ/b IEEE802.15.6/proprietary-MICS/ISM-band transceiver with scalable data-rate from 11kb/s to 4.5Mb/s for medical applications

The introduction of the IEEE802.15.6 standard (15.6) for wireless-body-area networks signals the advent of new medical applications, where various wireless nodes in, on or around a human body monitor vital signs. Radio communication often dominates the power consumption in the nodes, thus low-power transceivers are desired. Most state-of-the-art low-power transceivers support only proprietary modes with OOK or FSK modulations, and have poor sensitivity or low data rate [1,2]. In this work, a 15.6-compliant transceiver with enhanced performance is proposed. First, the data-rate is extended to 4.5Mb/s to cover multi-channel EEG applications. Second, while a best-in-class energy efficiency of 0.33nJ/b is achieved in the high-speed mode, a dedicated low-power mode reduces the RX power further in low-data-rate operation. Third, a sensitivity 5 to 10dB better than the 15.6 specification is targeted to accommodate extra path loss due to shadowing effects from human bodies