Using V/I Signature Patterns to Troubleshoot Bus Circuitry

bad solder joint on IC

One of the more difficult types of electronic repair tasks is troubleshooting bus structures on complex digital microprocessor based circuit boards. Many identical address and data bus lines share the same electrical characteristics and make the fault finding process a challenge. However, you can use the repeating nature of this digital structure to your advantage. When […]

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Look Close then look CLOSER! The Importance of good Circuit Board Inspection.

One of the first steps in troubleshooting an electronic circuit board is to perform a visual inspection. We did this with a recent stepper motor driver that had failed and did not see any issues. The next step involved building a signature analysis test to perform some power-off diagnostics. This process took about a half-hour […]

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Troubleshooting a Switching Power Supply – Part 1

We recently received a switching power supply that failed in the field so we took the opportunity to do some troubleshooting and discuss the process here on CircuitBoardProblems.com! Of course, like any good troubleshooters (and according to the PCB Troubleshooting Flowchart) we gave the power supply a good visual inspection. On the bottom side of […]

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