A Low-Noise Sub-Bandgap Reference with a ±0.64% Untrimmed Precision in 16nm FinFET

Description

We present a simple, yet robust architecture to achieve accurate temperature sensing without the need for costly calibration. For the first time, the active bulk diode of a standard CMOS process is utilized in replacement of BJT devices. Two such diodes are forward biased by a charge pump, which periodically discharges two sampling capacitors across the diodes. The sampled voltages are then combined to generate PTAT and CTAT signals. A passive charge-balancing scheme creates a digital output, which only requires a comparator, an 8-bit capacitive divider and SAR logic. Occupying 2500 μm 2 active area in 16-nm FinFET, the sensor operates down to 0.85 V and features intrinsic supply robustness. It achieves an uncalibrated accuracy of +1.5/-2.0 °C (min/max) across the consumer temperature range, and dissipates 230 pJ in a 12.8 μs conversion time. Due to the simplicity and low analog content of this concept, it is insensitive to future scaling and well suited for use at multiple locations in SoCs.

Period	05 Nov 2019
Event title	Asian Solid State Circuit Conference (A-SSCC)
Event type	Conference
Location	MacaoShow on map