1. Proper grounding: Ensuring that the PCB is properly grounded can help dissipate any excess electromagnetic energy and reduce the likelihood of interference.
2. Shielding: Implementing shielding techniques, such as adding grounded shields or using conductive materials, can help contain electromagnetic interference and prevent it from affecting other components.
3. Layout optimization: Carefully designing the layout of the PCB, avoiding crossing high-current traces with sensitive signal traces, can help minimize electromagnetic interference. Additionally, routing signal traces away from switching components can also help reduce interference.
4. Filtering: Incorporating filters, such as capacitors and inductors, in the PCB design can help attenuate high-frequency noise and prevent it from propagating throughout the circuit.
5. Use of ferrite beads: Adding ferrite beads to the power and signal lines connected to the relay can help suppress electromagnetic interference and prevent it from impacting other components on the PCB.
By implementing these solutions, designers can effectively reduce the impact of electromagnetic interference caused by the frequent actions of small relays on multilayer PCBs, ensuring the overall reliability and performance of the circuit.
1) Enhance Chip Anti-Interference Ability: Replace the PCB multi-layer circuit board CPU with a super anti-interference chip. Install a ceramic decoupling capacitor between the CPU and the power port of the decoder, ensuring that the ground terminal is positioned as close to the chip as possible. Shorter pins are preferred for optimal performance.
2) Suppress Interference Sources: Use a Darlington IC module with continuous current function (such as ULN2004A) for the relay drive amplifier to effectively eliminate interference caused by back electromotive force when the coil is cut off. Choosing a suitable relay for the PCB multi-layer circuit board or plating a layer of copper foil with medium thickness on the PCB can also effectively prevent electromagnetic interference.
Reduce the opening length or width of the PCB multi-layer circuit board template by 10% to 30% compared to the pad size to decrease the amount of solder paste deposition. The shape of the template opening should be selected carefully (e.g. triangle, teardrop) to minimize solder paste on narrow pitch pads. Use a compromise template thickness that suits both narrow pitch pads and non-narrow pitch pads, eliminating the need for multiple template thicknesses for different pads.
WellCircuits Limited is a manufacturer specializing in high-precision double-sided, multi-layer, impedance-controlled, blind buried vias, and thick copper circuit boards. Our product range includes HDI, thick copper, backplanes, rigid-flex combinations, buried capacitance, buried resistance, Golden Finger, and other specialized circuit boards to meet various customer requirements.
