RF ESD Protection Circuit Layout With Near-Zero Parasitic Inductance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronic devices face damage from static electricity due to inadequate electrostatic protection, particularly in radio frequency circuits, where parasitic inductance from lead connections can delay the activation of protection circuits, leading to potential damage from electrostatic energy.
Innovation Solution
An electronic device design featuring an electrostatic protection circuit connected in parallel with a radio frequency circuit, with a short trace distance to minimize parasitic inductance, and additional components like capacitive and inductive components forming a filter to isolate direct current and filter high-frequency electrostatic energy, ensuring timely activation of the protection circuit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the electrostatic protection circuit is connected with lead connections, then the circuit can be assembled and connected, but parasitic inductance is generated which delays the activation of the protection circuit
Solution Approach 1:
The patent extracts and eliminates the lead connections between the electrostatic protection circuit and the radio frequency circuit. By removing these physical connections, the parasitic inductance that caused activation delay is eliminated, allowing the protection circuit to activate immediately when electrostatic damage occurs.
Solution Approach 2:
The electrostatic protection circuit and the radio frequency circuit are merged into a single integrated circuit board without separate lead connections. This integration eliminates the parasitic inductance of leads and ensures that the protection circuit activates simultaneously with the radio frequency circuit, improving protection effectiveness while reducing activation delay.
2Ease of manufacture
If lead connections are used to connect the electrostatic protection circuit, then the circuit can be assembled, but parasitic inductance causes voltage difference that prevents timely activation
Solution Approach 1:
Both the electrostatic protection circuit and the radio frequency circuit are integrated on the same circuit board with shared ground connections, eliminating separate lead connections. This merging approach maintains ease of manufacture through standard PCB fabrication while eliminating parasitic inductance to ensure timely protection activation.
3Ease of manufacture
If the trace distance between the electrostatic protection circuit and radio frequency circuit is long, then the layout is easier, but the parasitic inductance increases and protection effectiveness decreases
Solution Approach 1:
The electrostatic protection circuit and radio frequency circuit are merged on the same circuit board with minimal trace distance between them. The shared ground connection and close proximity eliminate parasitic inductance while maintaining ease of manufacture through standard PCB design practices.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces parasitic inductance, allowing the electrostatic protection circuit to activate promptly and protect the radio frequency circuit from electrostatic damage, while also filtering out high-frequency components to prevent thermal failures and signal attenuation.
Implementation Method 1
the circuit board further comprises a capacitive component, wherein the antenna and the first end of the first electrostatic protection circuit are electrically connected to a first end of the capacitive component
Implementation Method 2
the circuit board further comprises an inductive component, wherein the second end of the capacitive component is electrically connected to a first end of the inductive component
Implementation Method 3
the inductive component and the capacitive component form a filter, wherein a frequency of a filtered signal corresponding to the filter is negatively correlated with an inductance value of the inductive component
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The present disclosure relates to an electronic device. The electronic device includes a circuit board comprising a first electrostatic protection circuit (111) and a protected circuit (112); a housing; and an antenna (120) electrically connected to a first end of the first electrostatic protection circuit and a first end of the protected circuit. A second end of the first electrostatic protection circuit is electrically connected to a first ground point, a second end of the protected circuit is electrically connected to a second ground point, and the first electrostatic protection circuit is connected in parallel with the protected circuit. A trace distance between the second end of the first electrostatic protection circuit and the second end of the protected circuit is less than a first threshold, so that a parasitic inductance therebetween approaches zero.