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Carbon nanotube (CNT) field-effect transistors (CNFETs) promise significant energy efficiency benefits versus today's silicon-based FETs. Yet despite this promise, complementary (CMOS) CNFET analog circuitry has never been experimentally demonstrated. Here we show the first reported demonstration of full CNFET CMOS analog circuits. For characterization, we fabricate analog building block circuits: multiple instances of two-stage op-amps. These CNFET CMOS op-amps achieve gain >700 (maximum derivative of output voltage with respect to differential input voltage), operate at a scaled sub- 500 mV supply voltage, achieve high linearity (even when operating at these scaled voltages), and are robust over time (minimal drift over >10,000 cycled measurements over 12 hours). Additionally, we demonstrate a front-end analog sub-system that integrates a CNFET-based breath sensor with an analog sensor interface circuit (transimpedance amplifier followed by a voltage follower to convert resistance change of the chemoresistive CNFET sensor into a buffered output voltage). These experimental demonstrations are the first reports of CNFET CMOS analog functionality that is essential for a future CNT CMOS technology.
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Spintronic/CMOS-Based Thermal Sensors
Stacking more systems into a compact area or scaling devices to increase the density of integration are two approaches to provide greater functional complexity. Excessive heat generated as a result of these technology advancements leads to an increase in leakage power and degradation in system reliability. Hence, a thermal aware system composed of hundreds of distributed thermal sensor nodes is needed. Such a system requires an efficient thermal sensor placed close to the thermal hotspots, small in size, fast response, and CMOS compatibility. In this paper, two hybrid spintronic/CMOS circuits are proposed. These circuits exhibit a low power consumption of 11.9 μW during the on-state, a linearity (R^2 ) of 0.96 over the industrial temperature range of operation (-40 to 125) o C, and a sensitivity of 3.78 mV/K.
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- Award ID(s):
- 1716091
- PAR ID:
- 10293277
- Date Published:
- Journal Name:
- Proceedings of the International Symposium on Circuits and Systems
- Page Range / eLocation ID:
- 1 to 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ISCAS45731.2020.9181023
