Circuit radar device

Abstract

The invention discloses a circuit radar device which is capable of accurately positioning faulty components (resistor, capacitor or inductor) on a circuit board. The circuit radar device comprises a power module, a signal generation module, a signal receiving and preprocessing module, a testing cable and a probe, a high-speed sampling analysis module, and a touch input and display module. The signal generation module is used for generating a testing periodic pulse signal which is input into a micro-strip wire to be tested, and meanwhile, the signals of a signal transmission end and the point of a receiving probe on the micro-strip wire are acquired, and then a reflection coefficient is calculated and the positions of various impedance discontinuous points are judged, and therefore, the positions of the faulty components can be found out. The circuit radar device is capable of positioning all the faulty components on the micro-strip wire to be tested online through once measurement.

Description

technical field [0001] The invention relates to the field of circuit board fault testing, in particular to a circuit radar device for measuring the wiring impedance of a printed circuit board by a time domain reflection (TDR) method, calculating the reflection coefficient, and judging the position of a short circuit point on the road. Background technique [0002] During the debugging process of circuit boards, debuggers often encounter faults caused by components, such as open circuit, short circuit, and component value mismatch. When encountering these faults, it is often only possible to remove all components corresponding to the faulty node one by one, and perform a fault test every time a component is removed, until the fault disappears after a certain component is removed, and the debugger can judge the specific faulty component , the troubleshooting process is very cumbersome, and the process is even more complicated when there are multiple faulty components. [0003...

AI Technical Summary

Problems solved by technology

The traditional TDR test method is to only sample the step signal at the sending end, and draw the "reflection coefficient-time" curve after high-speed sampling of the signal transition edge, and then calculate the impedance discontinuity point according to the speed of signal transmission in the PCB trace ( Impedance mismatch point), because the electrical signal transmission speed is very fast, the time error of the instrument leads to inaccurate position positioning, the fault point cannot be accurately located, and the faulty component cannot be accurately located

[0006] The instruments used to measure trace impedance are mainly time-domain reflectometers and network analyzers, but these proprietary instruments are expensive, often costing hundreds of thousands or millions, which is often unacceptable to ordinary designers

[0007] When encountering a short-circuit fault, most debuggers mainly use the method of removing the connected components to eliminate and secant one by one, and it is impossible to judge the short-circuit point by on-road measurement

In high-frequency circuits, secant lines can cause impedance discontinuities that can wreak havoc on signal integrity and can even cause a designed system to fail entirely

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