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印制板(PWB)和其他电子元器件的质量似乎一直在不断改进。因 此,最近很少见到由于板本身的制造缺陷或失效的元件引起的电路板走线之间的短路现象。然而,特别是用手工组装的样机有时仍然会发生短路。当发生这种现象时,寻找游离的铜屑、焊锡污点或短路元器件,可能是非常艰难的,这涉及到走线的切断/修补和不必要地拿掉良好部件。 本文所示的电池供电短路定位器利用电路板连线本身的小而可测量的电阻,再配上一个低压激励电流一起直接找出不良连接(见图),因而可大大地缩短诊断过程。典型输入失调电压为±
The quality of printed circuit boards (PWBs) and other electronic components seems to be constantly improving. Therefore, it is seldom seen recently that there is a short circuit between board traces due to board manufacturing defects or failed components. However, prototypes, especially those assembled by hand, sometimes still experience short circuits. When this happens, it can be very difficult to look for free copper chips, solder stains or short-circuit components, which involve the disconnection / repair of traces and the unnecessary removal of good components. The battery-operated short-circuit positioner shown here uses the small, measurable resistance of the board’s wiring itself, along with a low-voltage excitation current to find the bad connections directly (see figure), thereby greatly reducing the diagnostic effort. Typical input offset voltage is ±