How to Handle Sensitive Circuits on a PCB
(1) Power Cord
When designing the power line for a printed circuit board, it is important to consider the current and make the power line width thicker to reduce loop resistance. Pay attention to the direction of power supply and ground wire, ensuring it is opposite to the direction of data and signal transmission. This helps to enhance the anti-noise ability and should be from the final stage to the front stage.
(2) Ground Design
The principle of ground design is to separate digital and analog circuits as much as possible. If the circuit board contains both logical and linear circuits, they should be kept separate. Low frequency circuits should use single point parallel grounding whenever possible, and high frequency circuits should adopt multi-point serial grounding. Ground wires should be thickened to ensure they can handle the current on the printed board.
Interference Elements on the PCB
Interference Elements on the PCB can come from sources such as lightning, relays, silicon controlled, motors, and high frequency clocks. Interference can propagate through conduction along wires and through radiation in space. Sensitive components include A/D and D/A converters, single chip microcomputers, digital ICs, and weak signal amplifiers.
Types of Interference
Interference on a PCB can be divided into radiation and conduction. Radiation interference uses space as a medium to interfere with signals, while conductive interference uses a conductive medium as a path.
Dealing with Sensitive Components on a PCB
When placing components on a PCB, consider production and maintenance convenience. Ensure that capacitors are of the same polarity and place heat components and sensitive components apart. If components are moisture-sensitive and packaged in a tape-and-reel system, the exposure time must be carefully managed to avoid moisture damage.
(1) Power Cord
When designing the power line for a printed circuit board, it is important to consider the current and make the power line width thicker to reduce loop resistance. Pay attention to the direction of power supply and ground wire, ensuring it is opposite to the direction of data and signal transmission. This helps to enhance the anti-noise ability and should be from the final stage to the front stage.
(2) Ground Design
The principle of ground design is to separate digital and analog circuits as much as possible. If the circuit board contains both logical and linear circuits, they should be kept separate. Low frequency circuits should use single point parallel grounding whenever possible, and high frequency circuits should adopt multi-point serial grounding. Ground wires should be thickened to ensure they can handle the current on the printed board.
Interference Elements on the PCB
Interference Elements on the PCB can come from sources such as lightning, relays, silicon controlled, motors, and high frequency clocks. Interference can propagate through conduction along wires and through radiation in space. Sensitive components include A/D and D/A converters, single chip microcomputers, digital ICs, and weak signal amplifiers.
Types of Interference
Interference on a PCB can be divided into radiation and conduction. Radiation interference uses space as a medium to interfere with signals, while conductive interference uses a conductive medium as a path.
Dealing with Sensitive Components on a PCB
When placing components on a PCB, consider production and maintenance convenience. Ensure that capacitors are of the same polarity and place heat components and sensitive components apart. If components are moisture-sensitive and packaged in a tape-and-reel system, the exposure time must be carefully managed to avoid moisture damage.
