A 0.5V 180nm CMOS SwitchedCapacitor Temperature Sensor with 319 nJmeasurement In this paper an ultralowpower switchedcapacitor (SC) temperature sensor realized in a 180 nm CMOS process is introduced. The sensor is operational at supply voltages down to 0.5 V, equivalent to the threshold voltages of the available MOS transistors. Using bipolar transistors for reference and temperature dependent voltage generation in a SC bandgap core, the overall temperature sensor is formed by a combination of the bandgap with a timediscrete pseudodifferential singleslope analogtodigital converter. The temperature sensor has a power consumption of 2.62 xc2xb5W (4.56 xc2xb5W) including all biasing and clock generation at supply voltages of 0.5 V (0.8 V), and achieves an estimated 3xcfx83 accuracy of 2.42xc2xb0C (1.36xc2xb0C) using a twopoint trim for the temperature range of 10xc2xb0C to 100xc2xb0C (xe2x88x9220xc2xb0C to 100xc2xb0C). Besides the temperature sensing functionality, the presented circuitry additionally provides a 24 kHz clock signal and stable reference voltage for other circuit blocks.

Sub0.1V Input, LowVoltage CMOS Driver Circuit for MultiStage Switched Capacitor Voltage Boost Converter This paper proposes an extremelylowvoltage CMOS driver circuit for multistage switchedcapacitor (SC) voltage boost converter (VBC). The SC VBC using a conventional driver could not generate sufficient boosted clock signals when the input voltage becomes low. This is because the output voltages of the driver degrade significantly as the input voltage decreases. To mitigate the problem, we develop the lowvoltage CMOS driver circuit to improve the lowvoltage operation of the SC VBC. The proposed driver consists of a ring oscillator, nonoverlap clock generator, and main driver (MD) circuits. Simulated results demonstrated that the proposed driver can generate sufficient amplitude of the clock signals and the SC VBC using the proposed driver generates a 600mV output from a 100mV input when the voltage conversion ratio of the VBC is set to 6. The peak efficiency was 48.9% at 120nA load current. The driver circuit can operate at 79mV input voltage.