All-Digital Time-Domain Smart Temperature Sensor With an Inter-Batch Inaccuracy of $-{\hbox {0.7}} ~^{\circ}{\hbox {C}}-+{\hbox {0.6}}~^{\circ}{\hbox {C}}$ After One-Point Calibration

An all-digital self-calibrated delay-line based temperature sensor for VLSI thermal sensing and management

“…The DLL delay is designed to be independent of temperature. In [12], all the sensors' digital outputs are made to be the same at 50 1C (the calibration temperature). This is performed by adjusting the number of the circulation cycles in each sensor's cyclic delay line with an off-chip time-domain phase detection circuit.…”

“…This further increases the number of temperature sensors needed on-chip. The delay-line based temperature sensors [10][11][12][13] are area and power efficient designs. They can be fully synthesizable, making them more suitable for on-chip thermal monitoring, compared to their bandgap based counterparts [14][15][16][17].…”

“…At the same time, effective calibration methods are indispensable for temperature sensors in mass production. This is because the outputs of delay-line based temperatures sensors can vary significantly due to process variations [11,12].…”

A High-Resolution All-Digital Temperature Sensor with Process Variation Compensation

“…(2)(3)(4)(5)(6)(7)(8)(9) Compared with analog sensors, digital sensors offer advantages of higher system integration and lower area consumption. However, process variation affects the measurement accuracy.…”

“…(3)(4)(5)(6) One method calibrates the sensing elements directly, whereas another method changes the time domain to reduce the effect of process variation. (3,5,6) The second method is superior, because process variation compensation technology is integrated to the primary circuit and offers the advantages of low power and area consumption.…”