| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce local oscillator leakage when reducing output power. <P>SOLUTION: A circuit receives a first signal and mixes it with a local oscillator (LO) signal, and outputs a second signal (for example, an RFOUT signal). The circuit includes multiple identical Mixer and Frequency Divider Pair (MFDP) circuits. Each MFDP can be enabled separately. Each MFDP includes a mixer and a frequency divider that provides the mixer with a local version of the LO signal. The MFDP outputs are coupled together so that the output power of the second signal (RFOUT) is the combined output powers of the various MFDPs. By controlling the number of enabled MFDPs, the output power of the second signal is controlled. Because the MFDPs all have identical layouts, accuracy of output power step size is improved. LO signal power within the circuit automatically changes in proportion to the number of enabled MFDPs. <P>COPYRIGHT: (C)2012,JPO&INPIT |
