| 摘要 |
A quadrature oscillator 227 with phase error correction including a local oscillator 229 that generates a single-ended clock signal, a single-ended to differential converter 301, 303 that converts the clock signal to a differential clock signal, a quadrature generator 305, 307 that converts the differential clock signal into I and Q carrier signals, a phase error detector 313 that measures a phase error between the I and Q carrier signals, and a feedback amplifier 317, 319 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 A1-Q4, 405 converts the differential clock voltage signal into two pairs of differential current clock signals Ca, Cb, where the quadrature generator generates I and Q current signal outputs from the two pairs of differential current clock signals. The phase error detector generates a phase error voltage E2, and the feedback amplifier includes a transconductance stage 601, 603, 605 that converts phase error voltage into a DC correction current and that adds the correction current to each of he two pairs of AC differential current clock signals.
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