The Design Of An Anti-voltage Jitter And High Precision Time Domain Temperature Sensor

On-chip temperature sensors are particularly important for temperature management systems for VLSI circuits.Compared with the traditional temperature sensor based on the voltage domain,the temperature sensor based on the time domain is more suitable as an on-chip temperature sensor.Because the voltage has a great influence on the transmission characteristics of the transistor,the existing time-domain temperature sensor cannot effectively reduce the error caused by the voltage fluctuation in a wide voltage range.The Io T has a strong demand for low power consumption,and a reduction in operating voltage can effectively reduce the overall power consumption of the chip.Therefore,it is urgent to design and study a time-domain temperature sensor that can operate under a wide voltage range.In this thesis,a wide-voltage time-domain digital temperature sensor based on segmented compensation is proposed from the circuit level and architecture level respectively,which quantifying the ratio of different ring oscillators'frequencies for temperature sensing.Load transistors are added to the delay unit of the sampling ring to increase the load capacitance.The negative voltage coefficient of the load capacitor can offset the positive voltage coefficient that exists in the frequency ratio,and achieves the effect of voltage compensation under the high voltage range.In order to reduce the high voltage coefficient of the frequency ratio at low voltage,a sampled ring oscillator with different parameters is designed in this structure.By adding two frequency ratios to reduce the voltage sensitivity of the sensor in the low voltage region.In order to further reduce the voltage sensitivity of the sensor,a wide-voltage time-domain digital temperature sensor based on multi-loop complementarity is proposed based on this structure.This structure uses different sampling ring oscillators in the high and low voltage regions,and adjusts the parameters of the load transistor in each ring oscillators'delay unit.Two frequency ratios with opposite voltage coefficients in the high and low voltage regions are obtained.They are added together to offset the effect of the voltage change on the sensor output value,so as to obtain low voltage sensitivity under a wide voltage range.This thesis is based on the SMIC 40nm process,and builds the sensor analog circuit part in the Cadence Virtuoso environment.After that,it was integrated in the digital physical design process to complete the layout of the overall sensor.The experimental results show that the area of the time domain digital temperature sensor of this structure is only 0.014mm~2,and the maximum measurement error between the measurement temperature of 0°C and 100°C is±0.7°C.When the power consumption is 16.7n J,the measurement time is 42.The average voltage sensitivity between 0.7V and 0.9V is 0.011°C/m V.The average voltage sensitivity between 0.9V and 1.1V is 0.029°C/m V,which is 14.7%higher than the existing traditional structure.