Subthreshold-Hybrid Solutions for Thermal Sensor and Reference Circuits in Advanced CMOS
Sprache des Vortragstitels:
Englisch
Original Tagungtitel:
VLSI-SoC 2020
Sprache des Tagungstitel:
Englisch
Original Kurzfassung:
We present a family of hybrid structures, which
combine subthreshold MOS operation with a single bipolar
transistor. In contrast to typical BJT-based circuits, the PTAT
voltage is generated from an asymmetric differential pair in
weak inversion, and only the CTAT part depends on the
parasitic PNP. A common feature is the signal generation and
processing within a single feedback loop, which yields
specifically simple solutions, with enhanced robustness towards
supply and device variations. The bandgap reference, realized
in 14/16nm FinFET, provides a 600mV output and > 60dB
PSRR, at sub-1V power supply. We further present
temperature sensors in 28nm CMOS and 14/16nm FinFET,
which feature very low complexity and power. The first sensor
includes a SAR ADC and achieves a precision of ± 3 °C after a
1-point trim under production conditions. The FinFET sensor
variant is a scaling-friendly solution, providing enhanced
resolution with a duty-cycle modulated output.