HASL 3.5MM Double Layer FR4 3OZ Thick Copper PCB

Product Specification

2 Layer Thick Copper PCB

PCB Specifications:

Layer Count: 2 Layer PCB

Material: FR4, IT180A

Board Thickness: 3.5MM

Min Hole: 0.3MM

Min Trace: 20/10Mil

Copper: 3/3OZ

Solder Mas: Green

Unit Size: 165MM*144MM/1pcs

Surface Treatment: HASL

Application: Power Supply

Capabilities:

FAQ:

Question: What is Loss Tangent?

Answer: In PCBs, Loss tangent (tan (δ)) is the measure of signal loss due to the inherent dissipation of electromagnetic energy in the substrate of the printed circuit board. It is a dimensionless quantity and generally referred to: Loss Factor, Tan δ, Dissipation factor and Loss angle.

All PCB materials have both conduction losses and dielectric losses. The conduction losses are resistive and are caused by the conductive copper layer used in the board. The dielectric losses on the other hand are associated with the substrate (insulating material) used in a PCB. When the electric field is applied, polarization occurs and charges are displaced relative to the electric field. Dielectric losses cause a reduction in the overall electric field.

The total amount of polarization that can occur in a dielectric depends upon the molecular symmetry of the insulator material and is called Dipole Moment. The effect of the dipole moment in a dielectric substrate is termed Loss Tangent.

Mathematically, the loss tangent is the phase angle between the resistive and reactive components of a system with permittivity. A low value of loss tangents results in a "fast" substrate while large value results in a "slow" substrate.

The formula for Loss Tangent or the Dissipation Factor is:

where δ is the loss angle, θ is the phase angle, f is the frequency, Rp is the equivalent parallel resistance, and Cp is the equivalent parallel capacitance.

The signal loss by the dielectric material depends upon the material’s structure and glass-resin composition. Selection of low loss materials is the major task for manufacturers that is why they are advised to plot the attenuation equation against frequency for various material choices.

Loss tangent plays a crucial factor for very high frequencies above 1 GHz and analog signals to determine the signal attenuation.

Quesion: What is the Solder Mask?

Answer: Solder mask or solder resist is a coating applied to a Printed Circuit Board (PCB) to protect the copper traces on the board and to stop electrical shorts. The solder mask is usually applied on both sides of the PCB i.e Top and Bottom to ensure reliability and performance.

The solder mask is a Liquid UV Photo-imageable Ink which is usually green in color. Other color options like red, blue, yellow, white, black and purple are also available. This is something you need to ask your PCB fabricator.

In the image above, the light green line is the solder mask layer. As you can see, the solder mask covers the entire trace, leaving only the pads exposed which are required to make electrical connections.

What is the purpose of using a solder mask?

• To prevent short circuits and protect the copper traces on the board.
• To protects the traces from exposure to air which can cause oxidation and corrosion of traces.

What material is used for solder mask?

Resin is usually selected as the main material for solder mask because it works exceptionally well in terms of humidity resistance, insulation, solder resistance and high-temperature resistance.