公开(公告)号：US12028024B2

公开(公告)日：2024-07-02

申请号：US16705868

申请日：2019-12-06

申请人： Silicon Laboratories Inc.

发明人： Rangakrishnan Srinivasan ,  Mustafa H. Koroglu ,  Zhongda Wang ,  Francesco Barale ,  Abdulkerim L Coban ,  John M. Khoury ,  Sriharsha Vasadi ,  Michael S. Johnson ,  Vitor Pereira

IPC分类号： H03F1/26 ,  H03B5/04 ,  H03F1/30 ,  H03F3/24 ,  H03K5/00

CPC分类号： H03F1/26 ,  H03B5/04 ,  H03F1/30 ,  H03F3/245 ,  H03K5/00 ,  H03F2200/375 ,  H03K2005/00019

摘要： A transmitter including a frequency synthesizer with a voltage-controlled oscillator that provides an oscillating signal, a programmable delay circuit that delays the oscillating signal to provide a delayed oscillating signal, a power amplifier that is configured to use the delayed oscillating signal for transmitting a signal, and a delay controller that programs the delay circuit with a delay time that reduces interference caused by coupling from the power amplifier to the voltage-controlled oscillator. The delay circuit may be programmed to reduce control voltage change of the voltage-controlled oscillator as a function of delay change, and/or to reduce phase noise degradation at an output of the transmitter as a function of delay change. The delay may be adjusted based on detected operating temperature. A calibration value may be determined at a calibration frequency, in which a frequency offset may be determined based on a selected channel frequency.

公开(公告)号：US11353903B1

公开(公告)日：2022-06-07

申请号：US17219225

申请日：2021-03-31

申请人： Silicon Laboratories Inc.

发明人： Abdulkerim L Coban

IPC分类号： G05F1/567 ,  G05F3/26 ,  G05F1/445 ,  G05F1/46

摘要： A voltage reference circuit that can operate in a large supply voltage range with high PSRR, that dissipates low-power for a given output noise, and that has a low temperature-coefficient (TC) across a wide-temperature range. The voltage reference circuit does not require any calibration for low TC and high PSRR, occupies a relatively small circuit area, may be used without additional supply filtering in noisy or high-ripple supply environments, and is more robust against device mismatch effects particularly compared to designs based on sub-threshold operations. The voltage reference circuit is a special form of constant transconductance circuit that uses current mirror ratios that are chosen to achieve high PSSR and low noise properties. The device saturation voltage may be chosen so that flat temperature characteristics may be achieved.