Patent ID: 11965919
Assignee: ZHEJIANG UNIVERSITY
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G

Claim 1:
2. The phase frequency detector-based high-precision feedback frequency measurement apparatus according to claim 1, further comprising a charge pump (6), a low-pass filter circuit (7), and an (Analogue-to-Digital) A/D converter (8), wherein the charge pump (6) receives an output signal of the phase frequency detector (5) to generate a current output signal of a phase difference between the reference signal and the measured signal; the low-pass filter circuit (7) is connected to an output of the charge pump (6) to convert the current signal output by the charge pump (6) into a voltage signal, is connected to the A/D converter (8) to convert an analog signal into a digital signal, and transmits the digital signal to the FPGA (3); and the FPGA (3) outputs a measurement result when a stable state is reached.