Work and debugging methods before debugging

After the circuit is installed, it is usually not necessary to rush to power up. You should check it carefully.

The inspection contents include:

(1) Is the connection correct?

Check if the circuit connection is correct, including the wrong line (the end of the connection is correct, the other end is wrong), the less line (the line that is completely leaked during installation) and the multi-line (the two ends of the connection do not exist on the circuit diagram) .

There are usually two ways to check the line: 1) Check the installed circuit according to the circuit diagram: This method is characterized by checking the installed line one by one according to the circuit diagram connection, which makes it easier to find the wrong line and Less line. 2) Check the line according to the actual circuit according to the actual circuit: This is a method of checking the line with the component as the center. Check the connection of each component (including the device) pins at one time and check whether each of them is present on the circuit diagram. This method can not only find the wrong line and less lines, but also easily detect multiple lines.

In order to prevent errors, the marked lines should normally be marked on the circuit diagram, preferably with the pointer multimeter "Ω & times; 1" block, or the digital multimeter "Ω block" buzzer, and should be directly Measure component leads so that you can find out where the contact is bad.

(2) Component installation

Check for short-circuits between component leads; contactless connections; diodes, triodes, integrated devices, and electrolytic capacitor polarity are incorrectly connected.

(3) Whether the power supply (including polarity) and signal source connection are correct.

(4) Is there a short circuit between the power supply terminal and the ground?

If the circuit passes the above checks and is confirmed to be correct, it can be transferred to the debugger.

Debugging method:

Debugging includes both testing and tuning.

The so-called electronic circuit debugging is a series of measurement, judgment, adjustment, and re-measurement processes for the purpose of achieving circuit design specifications. In order to make the debugging go smoothly, it is better to design the circuit diagram to indicate the potential value of each point, the corresponding waveform diagram and other main data. The debugging method usually adopts the first adjustment and the joint adjustment (total adjustment).

We know that any complex circuit is composed of some basic unit circuits. Therefore, the direction of the signal can be adjusted during debugging to adjust the unit circuits step by step, so that the parameters basically conform to the design specifications. The core of this debugging method is: first debug the functional blocks (or basic unit circuits) that make up the circuit, and gradually expand the debugging range on the basis of this, and finally complete the debugging of the whole machine. The advantages of using the first split and the later joint adjustment are: to find problems and solve problems in time. Newly designed circuits generally use this method.

This method should be used for debugging electronic devices including analog circuits, digital circuits, and microcomputer systems. Because only after the three parts are separately debugged, the design specifications are respectively reached, and the signal and level conversion circuit can be used to realize the joint debugging of the whole machine. Otherwise, due to the mismatch of the input, output voltage and waveform required by each circuit, blindly joint debugging may cause a large number of device damage.

In addition to the above methods, one-off commissioning is also possible for products that have been finalized and products that need to work together to operate.