Abstract: A technique implements high impedance nodes using high threshold voltage devices that may generate less leakage current and may have a higher gate oxide breakdown voltage than standard devices in a particular manufacturing technology. Under at least one operating condition, for a particular power supply voltage, a circuit may be unable to produce a control signal that is sufficient to turn on such a high threshold voltage device. The technique adjusts the control signal voltage to provide a gate-to-source voltage sufficient to turn on the high threshold voltage device. At another power supply voltage, when the circuit is able to produce a control signal sufficient to turn on the high threshold voltage device, the technique does not adjust the control signal.

Abstract: A switched capacitor input circuit (200) includes an input buffer (210), a switched capacitor sampler circuit (220), and an integrator (250). The input buffer (210) has an input terminal for receiving an input voltage, and an output terminal. The switched capacitor sampler circuit (220) has an input terminal coupled to the output terminal of the input buffer (210), and an output terminal. The switched capacitor sampler circuit (220) includes a capacitor (222) and stores a charge proportional a voltage at the output terminal of the input buffer (210) in the capacitor (222) during a sample period, and transfers the charge from the capacitor (222) to the output terminal thereof during a transfer period subsequent to the sample period in a plurality of charge portions corresponding to a like plurality of phases of the transfer period. The integrator (250) has an input terminal coupled to the output terminal of the switched capacitor sampler circuit, and an output terminal for providing an output voltage signal.

Abstract: A switched capacitor sampler circuit (220) includes an input terminal (224) for receiving an input voltage, an output terminal (226), a capacitor (222) having first and second terminals, and a switching circuit (230). The switching circuit (230) is coupled to the input terminal (224), the output terminal (226), and the first and second terminals of the capacitor (222). The switching circuit (230) stores a charge on the capacitor (222) proportional to the input voltage during a sample period, and transfers the charge from the capacitor (222) to the output terminal (226) during a transfer period subsequent to the sample period. The switching circuit (230) transfers the charge in a plurality of charge portions corresponding to a like plurality of phases of the transfer period.