Hi guys,
i need help with my doc. I do have to inspection and assembly PCB board I this is my steps are
1-First, I will make sure the PCB board does not have any damage by visual inspection PCB and see if there is any scratch on the lines that will transfer the power.
2- Check the PCB for possible short or open line, using a multimeter to test the short and open line, open when infinite reading and shorted when there is zero reading while the multi-tester set in continuity or resistance option, I will use a digital multimeter and then start to connect -+15 and test the lines if they go to all nods as our planned. I will check the voltage and the current in the circuit with the multimeter and make sure the circuit got the power all the circuit.
3 Check the value of the components required to be installed, resistors, capacitor capacitance and polarity, transistor's pins which is the emitter, collector, check the polarity of the source voltage.
4- For the components, please verify all the resistor's resistance is correct, since we have a multimeter we will check if the value is correct for all components. Parts Value Results 5- During assembly, check the polarity of the components to be installed, the positive and negative polarity of the source, the polarity of capacitance, the position of the pins for the amplifier.
6. After solder, check if there is shorted line or open line using multi-tester, check the expected voltage drop in the load or other components, be careful using multi-tester for voltage check, it should be in voltage option and not in resistance. Make visual inspection again for PCB and touch some components if there is no unusual heat some components, otherwise, immediately disconnect to the source and check again for possible short circuit. Open circuit Short circuit Resistors Capacitors Amplifiers
The final test, keep the board running for quite some time and then touch some components if they do not draw too much heat, if so, let say an amplifier, does not have a normal temperature, which means there is something wrong with assembly, or there is a short circuit.
I got this feedback that i have to follow to make it perfect. Can you please help me with that?
1- Visual inspection: Good idea. How many boards are you going to inspect? 5 boards
2- PCB opens and shorts: You have the right idea here but you need more detail.
You need to list all the tests you are going to make. Below is a picture of the front and back of the pcb. I would edit the pcb layout image and note all the locations that you are going to test and then make a table. Before I assemble anything, I suggest drilling the holes for the standoffs. The screws are 4-40 size. You should be able to find out the size of a clearance hole for a 4-40 screw and put that in your document. Let me know if you need access to a drill.
3- I would make a list of all the components that are polarity dependent. Determining how they will physically go on the board is a good idea.
4- Checking the value of the resistors is a good idea, however to do the check you would need to open the bags and this can lead to the parts being interchanged. The chip resistors all look almost the same. What is your plan for making sure that the parts aren't interchanged. Verification just prior to assembly might be smarter.
5- You can add the soldering documentation as a post assembly inspection criteria to your document
6-Regarding the post assembly electrical testing, you will need to have the circuit powered. Again, take the image of the pcb and indicate and label the locations you want to test and make a table. As we discussed, you should have the expected values of the voltages in your table. With regards to components that are hot, since you don't have an infrared thermometer I don't think this will work.
If you notice components that are hot, you can disconnect the power and investigate but I don't think that this is a reliable part of your inspection criteria.
Also, one easy test you can do is to compare the calculated current consumption of the circuit with the actual values. Also you need to talk about testing the slow rate.
i need help with my doc. I do have to inspection and assembly PCB board I this is my steps are
1-First, I will make sure the PCB board does not have any damage by visual inspection PCB and see if there is any scratch on the lines that will transfer the power.
2- Check the PCB for possible short or open line, using a multimeter to test the short and open line, open when infinite reading and shorted when there is zero reading while the multi-tester set in continuity or resistance option, I will use a digital multimeter and then start to connect -+15 and test the lines if they go to all nods as our planned. I will check the voltage and the current in the circuit with the multimeter and make sure the circuit got the power all the circuit.
3 Check the value of the components required to be installed, resistors, capacitor capacitance and polarity, transistor's pins which is the emitter, collector, check the polarity of the source voltage.
4- For the components, please verify all the resistor's resistance is correct, since we have a multimeter we will check if the value is correct for all components. Parts Value Results 5- During assembly, check the polarity of the components to be installed, the positive and negative polarity of the source, the polarity of capacitance, the position of the pins for the amplifier.
6. After solder, check if there is shorted line or open line using multi-tester, check the expected voltage drop in the load or other components, be careful using multi-tester for voltage check, it should be in voltage option and not in resistance. Make visual inspection again for PCB and touch some components if there is no unusual heat some components, otherwise, immediately disconnect to the source and check again for possible short circuit. Open circuit Short circuit Resistors Capacitors Amplifiers
The final test, keep the board running for quite some time and then touch some components if they do not draw too much heat, if so, let say an amplifier, does not have a normal temperature, which means there is something wrong with assembly, or there is a short circuit.
I got this feedback that i have to follow to make it perfect. Can you please help me with that?
1- Visual inspection: Good idea. How many boards are you going to inspect? 5 boards
2- PCB opens and shorts: You have the right idea here but you need more detail.
You need to list all the tests you are going to make. Below is a picture of the front and back of the pcb. I would edit the pcb layout image and note all the locations that you are going to test and then make a table. Before I assemble anything, I suggest drilling the holes for the standoffs. The screws are 4-40 size. You should be able to find out the size of a clearance hole for a 4-40 screw and put that in your document. Let me know if you need access to a drill.
3- I would make a list of all the components that are polarity dependent. Determining how they will physically go on the board is a good idea.
4- Checking the value of the resistors is a good idea, however to do the check you would need to open the bags and this can lead to the parts being interchanged. The chip resistors all look almost the same. What is your plan for making sure that the parts aren't interchanged. Verification just prior to assembly might be smarter.
5- You can add the soldering documentation as a post assembly inspection criteria to your document
6-Regarding the post assembly electrical testing, you will need to have the circuit powered. Again, take the image of the pcb and indicate and label the locations you want to test and make a table. As we discussed, you should have the expected values of the voltages in your table. With regards to components that are hot, since you don't have an infrared thermometer I don't think this will work.
If you notice components that are hot, you can disconnect the power and investigate but I don't think that this is a reliable part of your inspection criteria.
Also, one easy test you can do is to compare the calculated current consumption of the circuit with the actual values. Also you need to talk about testing the slow rate.
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