A 65-nm Delta-Sigma ADC-Based VDD-Variation-Tolerant Power-Side-Channel-Attack Sensor

This letter describes a Delta-Sigma ADC based Power-Side-Channel-Attack Sensor. Use of 64 sampling capacitors allows the use of over-sampling architecture even with a decoupling capacitor connected to the power supply. The LDO with low-leakage S/H is used as a driver for the integrator’s amplifier to minimize the offset error. A differential conversion method utilizing Dual-Integrate capacitors (CAPs) provides signal processing to compensate for drift due to supply voltage (VDD) variations. The prototype sensor chip fabricated in 65nm CMOS has a worst-case detection accuracy of 98.7%, including VDD variations, for an insertion resistance >= 0.25Ω and a power consumption of 50uW at 1.0V operation.