How to debug a circuit board faster in Chongqing MCU development
Don't be afraid when you encounter a problem, the problem will definitely be solved, it's just a matter of time. As long as you are not overwhelmed by the problem, you will gain invaluable experience after solving the problem.
Most of the current circuit boards are of modular design, which means that the various functions required by the circuit boards are implemented as modular circuits one by one. Recently, I made a circuit board for the test equipment for the customer. It also adopts a modular design. In order to realize the predetermined function, the circuit board is divided into a power conversion module, a microprocessor module, a differential signal to a single-ended signal module, a relay module, and a signal Current output module and 485 module, etc. When designing the circuit board, it is designed as a whole. Different modules are placed on a circuit diagram for wiring, signal and parameter matching, and then processed into a circuit board. The previous is a relatively integrated process, because it is impossible to design or process half a circuit board.
No master can guarantee the perfect success of the circuit design at one time. After proofing and processing the circuit board, it is necessary to solder the components for debugging, which is an indispensable step for subsequent mass production of the circuit board.
Soldering all the components to the circuit board at once, and then powering on the circuit board is a more inertial working idea. If the originally designed circuit board has no major problems, debugging is relatively easy, but when the circuit board is defective , Debugging is more troublesome, because when you find that a certain function module has a problem, you can't easily determine whether it is the front or back of the module. Therefore, an effective suggestion summarized in practice is not to solder all the components at once, but to solder components one by one module by module according to the direction of the signal or energy flow. When the components of a module are soldered Perform a power-on test again to check whether the key parameters are abnormal. If there is an abnormality, you only need to check the components or wiring in this module to find out the problem easily, instead of being clueless and at a loss when facing the entire circuit board. After the debugging of this module is successful, the welding and debugging of the next module will be carried out. Such successful breakthroughs one by one will make the debugging of the circuit board easier. The tasks that need to be completed at each stage are:
l Soldering: accurately solder the components in the module to the circuit board, pay attention to visual inspection or use tools to check whether the solder joints or solder joints are short-circuited;
l Debug: Focus on checking whether the output of the module is consistent with the design target parameters.
The module welding and debugging of the circuit board is sequential. It must be ensured that the module needs the prerequisites and necessary conditions before the welding and debugging is completed. Generally speaking, according to the flow of signal and energy flow You can perform welding and debugging in the direction. In this circuit, you should first debug the power conversion module, because this is the basis for other modules to supply power, then debug the microprocessor module, because the microprocessor will coordinate the work of other modules, and then the differential to single-ended signal module and other modules Output modules, etc. When a module is successfully debugged one by one, the circuit board is completed.
Naturally, when debugging a microprocessor module, it may be accompanied by programming and development work, which is also indispensable.
To sum up, an effective method for circuit board debugging is to perform soldering and debugging one by one according to the module units. Soldering the components in the module in the order of the signal or power flow direction on the blank circuit board, and test and debug after a module is soldered. Until the output of the module is normal, then proceed to the welding and debugging of the next module until all modules are successful.