Abstract: A quadrature oscillator with phase error correction including a local oscillator that generates a single-ended clock signal, a single-ended to differential converter that converts the clock signal to a differential clock signal, a quadrature generator that converts the differential clock signal into I and Q carrier signals, a phase error detector that measures a phase error between the I and Q carrier signals, and a feedback amplifier that modifies the differential clock signal based on measured phase error. The feedback amplifier applies the measured phase error as a DC offset to an AC differential clock signal. A transconductor converts the differential clock voltage signal into two pairs of differential current clock signals, where the quadrature generator generates I and Q current signal outputs from the two pairs of differential current clock signals.

Abstract: A single-ended to differential converter including a common mode shunt and a load element. The common mode shunt includes first and second reactive elements each having first ends coupled together at a common mode junction. The second end of the first reactive element receives a single-ended input signal referenced to a reference signal, such as ground. The common mode shunt further includes a third reactive element coupled between the common mode junction and ground. The load element is coupled between the second end of the second reactive element and ground. A single-ended input signal is applied at a second end of the first reactive element and the differential signal is developed by the first and second reactive elements. The common mode shunt serves as a differential to single-ended converter by applying the differential signal as an input in which a single-ended output signal develops at the load element.

Abstract: A single-ended to differential converter including a common mode shunt and a load element. The common mode shunt includes first and second reactive elements each having first ends coupled together at a common mode junction. The second end of the first reactive element receives a single-ended input signal referenced to a reference signal, such as ground. The common mode shunt further includes a third reactive element coupled between the common mode junction and ground. The load element is coupled between the second end of the second reactive element and ground. A single-ended input signal is applied at a second end of the first reactive element and the differential signal is developed by the first and second reactive elements. The common mode shunt serves as a differential to single-ended converter by applying the differential signal as an input in which a single-ended output signal develops at the load element.

Abstract: A quadrature oscillator with phase error correction including a local oscillator that generates a single-ended clock signal, a single-ended to differential converter that converts the clock signal to a differential clock signal, a quadrature generator that converts the differential clock signal into I and Q carrier signals, a phase error detector that measures a phase error between the I and Q carrier signals, and a feedback amplifier that modifies the differential clock signal based on measured phase error. The feedback amplifier applies the measured phase error as a DC offset to an AC differential clock signal. A transconductor converts the differential clock voltage signal into two pairs of differential current clock signals, where the quadrature generator generates I and Q current signal outputs from the two pairs of differential current clock signals.