The functions of the precision frequency measurement technique in MCXO

The MCXO is not only a combination of a crystal oscillator with a microcomputer, but also based on same frequency measurement techniques and an automatic MCXO test system. A highly precision frequency measurement technique with a simple structure and a fast response time can be used in MCXO and its test system. It can be used to enhance the accuracy and stability of MCXO, simplify the structure of MCXO. This paper describes several very useful high-precision, fast response time frequency measurement techniques. These techniques are not only highly precision, of fast response time in a very wide frequency range, but also simple and all digital in circuit. By means of the techniques, with short gate times the measuring error is less than 10^-9. In many MCXOs and relative instruments, the highly precision measuring technique and circuits can be used in place of complicated frequency transformation and control circuits, and the devices can thus be simplified with their frequency stability enhanced and other advantages obtained. This paper also describes several different MCXO crystal oscillators, and proves the outstanding contributions of the highly precision measurement technique in the MCXO circuits for their performance