Frequency tracking synchronizing signal detection circuit

The utility model discloses a frequency tracking synchronizing signal detection circuit, which belongs to the technical field of synchronizing signal frequency discrimination phase lock detection and comprises a current transformer, a first comparator, a differentiating circuit and a phase frequency detector which are sequentially connected, the differentiating circuit comprises a capacitor C2 and a digital potentiometer, and two ends of the capacitor are respectively connected with a W end and a B end of the digital potentiometer. Because the differentiating circuit is composed of a capacitor C2 and a digital potentiometer, programmable digital frequency tracking is realized, parameter setting is convenient and flexible, the frequency tracking range is increased, batch production is facilitated, and product test and inspection time is saved. 本实用新型公开一种频率追踪同步信号检测电路，属于同步信号鉴频锁相检测技术领域，包括依次连接的电流互感器、第一比较器、微分电路和鉴频鉴相器，微分电路包括电容C2和数字电位器，电容的两端分别与数字电位器的W端和B端连接。由于微分电路由电容C2和数字电位器构成，实现可编程数字化频率追踪，参数设置方便且灵活，增加了频率追踪范围，便于批量生产，节