Abstract: Circuits that operate with power supplies of less than 1 Volt are presented. More particularly, circuits that operate with supply voltages near or lower than the threshold voltage of the transistors in those circuits are presented. Various circuits and embodiments such as operational transconductance amplifiers, biasing circuits, integrators, continuous-time sigma delta modulators, track-and-bold circuits, and others are presented. The techniques and circuits can be used in a wide range of applications and various transistors from metal-oxide-semiconductor to bipolar junction transistors may implement the techniques presented herein.

Abstract: Circuits that operate with power supplies of less than 1 Volt are presented. More particularly, circuits that operate with supply voltages near or lower than the threshold voltage of the transistors in those circuits are presented. Various circuits embodiments such as operational transconductance amplifiers (1101, 1102, 1103), biasing circuits, integrators (1113, 1123, 1133), continuous-time sigma delta modulators, track-and-hold circuits, and others are presented. The techniques and circuits can be used in a wide range of applications and various transistors from metal-oxide-semiconductor to bipolar junction transistors may implement the techniques presented herein.

Abstract: Disclosed are a device and a method for calibrating a frequency of a transponder applicable to an RFID system. The device may comprises: a pulse generating unit configured to generate a sequence of pulses based on a PIE symbol sequence from an interrogator of the RFID system; a counting unit configured to count clock cycles of a clock signal based on the generated pulses, wherein the transponder operates based on the clock signal; and a calibrating unit configured to calibrate a frequency of the clock signal towards a target frequency based on a comparison of the counted number of clock cycles with a reference number associated with the target frequency.

Abstract: Disclosed are a sensor interface device and an amplifier used in a sensor system. The sensor interface device in one implementation has a first chopper configured to shift input signals of the sensor system from a baseband frequency to a first frequency, an instrumentation amplifier configured to amplify the shifted signals, a bandpass Delta-Sigma modulator configured to digitize the amplified signals, and a second chopper configured to shift the digitized signals from the a first frequency back to the baseband frequency. The instrumentation amplifier removes the DC offset generated from the first chopper and therefore all sources of DC offset are eliminated in this interface device without bandwidth limitation.

Abstract: Circuits that operate with power supplies of less than 1 Volt are presented. More particularly, circuits that operate with supply voltages near or lower than the threshold voltage of the transistors in those circuits are presented. Various circuits embodiments such as operational transconductance amplifiers (1101, 1102, 1103), biasing circuits, integrators (1113, 1123, 1133), continuous-time sigma delta modulators, track-and-hold circuits, and others are presented. The techniques and circuits can be used in a wide range of applications and various transistors from metal-oxide-semiconductor to bipolar junction transistors may implement the techniques presented herein.

Abstract: Disclosed are a sensor interface device and an amplifier used in a sensor system. The sensor interface device in one implementation has a first chopper configured to shift input signals of the sensor system from a baseband frequency to a first frequency, an instrumentation amplifier configured to amplify the shifted signals, a bandpass Delta-Sigma modulator configured to digitize the amplified signals, and a second chopper configured to shift the digitized signals from the a first frequency back to the baseband frequency. The instrumentation amplifier removes the DC offset generated from the first chopper and therefore all sources of DC offset are eliminated in this interface device without bandwidth limitation.