How many issues require attention during the automotive PCB prototyping process? This chapter provides a detailed analysis of essential automotive PCB prototyping knowledge. Therefore, during the process of automotive PCB prototyping, special attention needs to be given to these eight aspects:
1. **Soldering Iron Usage:** Avoid using a live soldering iron. Ensure the soldering iron is not energized. It’s advisable to ground the soldering iron shell. Be particularly cautious with MOS circuits; using a low-voltage circuit iron (6~8V) enhances safety.
2. **Integrated Circuit Inspection and Repair:** Before inspecting and repairing integrated circuits, thoroughly understand their functions, internal circuits, key electrical parameters, pin roles, normal pin voltages, and circuit operation principles involving waveforms and peripheral components. Familiarity with these conditions significantly simplifies analysis and inspection processes.
When measuring the DC voltage of integrated circuit pins, choose a multimeter with an internal resistance greater than 20KΩ/V to minimize measurement errors, especially for sensitive pin voltages.
Power integrated circuits require effective heat dissipation and should not operate at high power levels without a heatsink.
During soldering, ensure proper solder flow to prevent solder accumulation and porosity, which can lead to poor connections. Limit soldering time to under 3 seconds, using a 25W internally heated soldering iron. Use an ohmmeter to check for short circuits between pins before powering on to ensure no unintended solder bridges.
When adding peripheral components to replace damaged parts inside integrated circuits, opt for small components and plan wiring carefully to prevent unnecessary parasitic coupling. Pay particular attention to grounding connections between the audio amplifier IC and the pre-amplification circuit.
Do not quickly conclude that an integrated circuit is damaged. The majority of integrated circuits are directly interconnected. Therefore, when a circuit exhibits abnormalities, it can result in various voltage fluctuations. These fluctuations may not necessarily indicate that the integrated circuit is damaged. Additionally, even if voltages measured at each pin appear normal or close to normal, it does not guarantee the integrated circuit is functioning properly. Certain intermittent faults do not manifest as changes in DC voltage.
When measuring voltages or testing waveforms using an oscilloscope probe, take care to avoid causing short circuits between the pins of the integrated circuit due to slipping of the probe. It is advisable to conduct measurements directly on the peripheral printed circuit board that is directly connected to the pins.
1. **Soldering Iron Usage:** Avoid using a live soldering iron. Ensure the soldering iron is not energized. It’s advisable to ground the soldering iron shell. Be particularly cautious with MOS circuits; using a low-voltage circuit iron (6~8V) enhances safety.
2. **Integrated Circuit Inspection and Repair:** Before inspecting and repairing integrated circuits, thoroughly understand their functions, internal circuits, key electrical parameters, pin roles, normal pin voltages, and circuit operation principles involving waveforms and peripheral components. Familiarity with these conditions significantly simplifies analysis and inspection processes.
When measuring the DC voltage of integrated circuit pins, choose a multimeter with an internal resistance greater than 20KΩ/V to minimize measurement errors, especially for sensitive pin voltages.
Power integrated circuits require effective heat dissipation and should not operate at high power levels without a heatsink.
During soldering, ensure proper solder flow to prevent solder accumulation and porosity, which can lead to poor connections. Limit soldering time to under 3 seconds, using a 25W internally heated soldering iron. Use an ohmmeter to check for short circuits between pins before powering on to ensure no unintended solder bridges.
When adding peripheral components to replace damaged parts inside integrated circuits, opt for small components and plan wiring carefully to prevent unnecessary parasitic coupling. Pay particular attention to grounding connections between the audio amplifier IC and the pre-amplification circuit.
Do not quickly conclude that an integrated circuit is damaged. The majority of integrated circuits are directly interconnected. Therefore, when a circuit exhibits abnormalities, it can result in various voltage fluctuations. These fluctuations may not necessarily indicate that the integrated circuit is damaged. Additionally, even if voltages measured at each pin appear normal or close to normal, it does not guarantee the integrated circuit is functioning properly. Certain intermittent faults do not manifest as changes in DC voltage.
When measuring voltages or testing waveforms using an oscilloscope probe, take care to avoid causing short circuits between the pins of the integrated circuit due to slipping of the probe. It is advisable to conduct measurements directly on the peripheral printed circuit board that is directly connected to the pins.
