Abstract:
A system involves a first SerDes link from a first integrated circuit (IC) to a second IC and a second link from the second IC to the first IC. Power consumption settings in circuitry of the first link are adjusted to control power consumption such that the bit error rate of the first link is maintained in a range, where the lower bound of the range is substantially greater than zero. Power consumption settings in circuitry for the second link are adjusted to control power consumption such that the bit error rate of the second link is maintained in range, where the lower bound of the range is substantially greater than zero. In one example, circuitry in the second IC detects errors in the first link and reports back via the second link. The first IC uses the reported information to determine a bit error rate for the first link.
Abstract:
An amplitude calibration element comprises a linear driver configured to receive the output of a modulator, the modulator output comprising a voltage signal having an amplitude modulated (AM) portion, a differential detector configured to receive an output of the linear driver and develop a differential signal corresponding to the AM portion, and a differential comparator configured to receive the output of the differential detector and a differential reference signal, the differential comparator configured to develop a gain control signal to control the gain of the linear driver.
Abstract:
A differential radio frequency (RF) receiver includes a fully differential direct conversion receive chain, a subharmonic mixer in the receive chain, the subharmonic mixer configured to receive a differential radio frequency (RF) input signal and a local oscillator (LO) signal that is phase-shifted by a nominal 45 degrees, and a synthesizer having a voltage controlled oscillator and having at least one frequency divider to generate desired receive LO signals.
Abstract:
A downconverter is provided. The downconverter includes a I mixer and a Q mixer. Each mixer includes a transconductance stage and a mixer core stage. The outputs of the transconductance stages of the mixers are shorted together, and a resistors are arranged in series with an input of the mixer core stages.
Abstract:
A variable gain frequency multiplier comprises a multiplier circuit and a control circuit configured to receive a power control signal, the power control signal being proportional to a power output signal.
Abstract:
A closed loop power control system for a radio frequency (RF) transmitter comprises a first variable gain element located in a power control loop and configured to receive a power level signal and an inverse representation of a power control signal, a second variable gain element located in the power control loop and configured to receive an error signal and the power control signal, and a third variable gain element configured to receive an amplitude modulated (AM) signal and the power control signal, the third variable gain element having a gain characteristic configured to operate to reduce the gain applied to the AM signal when the power control signal falls below a minimum predetermined value, and to provide the AM signal as a reference signal.
Abstract:
A quadrature subharmonic mixer comprises a polyphase filter configured to generate quadrature components of a local oscillator (LO) reference signal, a summing and scaling element configured to create additional components of the (LO) reference signal, and a plurality of mixer elements configured to multiply the quadrature components of the (LO) reference signal and the additional components of the (LO) reference signal with a radio frequency (RF) signal to obtain a downconverted version of the RF signal.
Abstract:
A bang-bang frequency detector with no data pattern dependency is provided. In examples, the detector recovers a clock from received data, such as data having a non-return to zero (NRZ) format. A first bang-bang phase detector (BBPD) provides first phase information about a phase difference between a sample clock and the clock embedded in the received data. A second BBPD provides second phase information about a second phase difference between the clock embedded in the received data and a delayed version of the sample clock. A frequency difference between the sample clock and the clock embedded in the received data is determined based on the first and second phase differences. The frequency difference can be used to adjust the frequency of the sample clock. A lock detector can be coupled to a BBPD output to determine if the sample clock is locked to the clock embedded in the received data.
Abstract:
A system for saturation detection and compensation in a power amplifier includes a power amplifier, a closed power control loop configured to develop a power control signal (V PC ), a comparator configured to receive the power control signal and a reference signal, the comparator also configured to determine whether the power amplifier is operating in a saturation mode, and power control circuitry configured to reduce the power control signal if the power amplifier is operating in a saturation mode.
Abstract:
A supply voltage controlled power amplifier that comprises a power amplifier, a closed power control feedback loop configured to generate a power control signal, and a dual voltage regulator coupled to the power control feedback loop, the dual voltage regulator comprising a first regulator stage and a second regulator stage, wherein the closed power control loop minimizes noise generated by the first regulator stage.