用于SoC电源噪声测量的低温漂VCO

A low temperature drift VCO for SoC power supply noise measurement

提出了适用于片上系统(SoC)电源噪声测量的带两级温度补偿的基于环路压控振荡器(ring VCO)的量化器。通过粗略和精细两级温度补偿电路得到更低温漂的ring VCO。在粗略补偿一级中,将正比于温(PTAT)的电流注入尾限流管控制的ring VCO中,用来补偿VCO中较大的温度系数;在精细补偿一级中,用一个VCO复制电路来感知温度的变化,并将感知到的温度变化信息传递给量化器中的VCO,从而进一步自适应调整VCO量化器的振荡频率。基于40 nm工艺,设计一款工作在1.1 V电源电压下的两级温度补偿ring VCO,并对其进行了电路仿真,其输出信号的振荡频率约为4.3 GHz,在-40℃~125℃的温度变化范围内,实现了15.5 ppm/℃的温漂值。

This paper presents a two-stage temperature compensated ring VCO-based quantizer for on-chip power supply noise measurement.To achieve a lower temperature coefficient,the coarse and fine temperature compensated stages are both exploited.In the coarse stage,a proportional-to-absolute-temperature(PTAT)current injects in the current starved ring VCO to compensate the large part of the temperature coefficient of the VCO,and as the fine compensated stage,a replica VCO is employed to sense temperature variation and further adjust the oscillation frequency of the VCO adaptively.The ring VCO-based quantizer is operated at a 1.1 V supply.The simulation results show the output frequency of the VCO is 4.3 GHz,and it achieves a low temperature sensitivity of 15.5 ppm/℃over the range from-40℃to 125℃with the two-stage temperature compensation.