Specific steps for electronic circuit debugging

(1) Power on investigation: After power on, do not rush to measure electrical targets, but investigate whether there are any abnormal phenomena in the circuit, such as smoking, abnormal odors, touching the outer packaging of the integrated circuit, and whether it is hot. If there is an abnormal phenomenon, the power should be immediately turned off and the fault should be resolved before turning it back on.

(2) Static debugging: Static debugging generally refers to a DC test conducted under the condition of no input signal or only a fixed level signal. A multimeter can be used to measure the potential of each point in the circuit. After comparing it with theoretical estimates and analyzing the circuit principle, it can determine whether the DC operation of the circuit is normal and timely discover damaged or critical components in the circuit. By replacing components or adjusting circuit parameters, the DC operation of the circuit meets the design requirements.

(3) Dynamic debugging: Dynamic debugging is carried out on the basis of static debugging. Suitable signals are added to the input of the circuit, and the output signals of each test point are sequentially detected according to the direction of the signals. If any abnormal phenomenon is found, the cause should be analyzed and the fault should be eliminated before debugging until the requirements are met.

During the testing process, it is not enough to rely solely on feelings or images, but to constantly rely on instruments for investigation. When using an oscilloscope, place the signal input method of the oscilloscope in the "DC" mode, and through the DC coupling method, the AC and DC components of the measured signal can be investigated simultaneously.

After debugging, check whether the various targets of the functional blocks and the whole machine (such as signal amplitude, waveform shape, phase correlation, gain, input impedance and output impedance, sensitivity, etc.) meet the design requirements. If necessary, further propose reasonable modifications to the circuit parameters.

Article source: Jiangmen single-sided and double-sided circuit boardhttp://www.yonghongpcb.com/