Skip to main content

澳洲5在线投注

LEARN PCB
PCB Manufacturing
PCB Assembly
PCB Design and Layout
PCB Basics
Vias, Drilling & Throughplating
Mechanics
Surface
SMD
Quality
SPECIFICATIONS
PCB Fabrication
STANDARDS & POLICY
PCB Ordering
Policy

澳洲53期计划

Printed circuit boards carry current through etched copper tracks. The current carrying capacity of a copper trace can be improved by increasing its width, but this is not always practical. Another way to increase the current carrying capacity without changing the width of the copper traces is to use heavy or thick copper. This carries more current and enhances efficiency with better heat management.

There are no definite rules that specify the amount of copper to be used when fabricating heavy copper boards. However, the PCB industry considers 3 or more ounces of copper on any circuit board layer as heavy copper.

heavy-copper-pcb.jpg
Heavy copper PCB

澳洲5开奖

澳洲5开奖官方同步

PCB designers gauge the amount of current required and based on this they design their heavy copper boards. This involves selecting the right copper thickness, width, and the maximum temperature rise the circuit board can withstand. The amount of heat a heavy copper board generates is proportional to the amount of current it carries.

trace-structure-of-a-pcb.jpg
PCB trace structure

How to choose the right copper thickness

As stated earlier, the copper thickness is determined by the current passing through the conductor. The thickness of the board can be determined by a trace width calculator. It can calculate the three parameters that include trace width, current capacity, and temperature rise. If any two parameters are known, the tool calculates the third.

trace-width-calculator.jpg
Sierra Circuit trace width calculator

澳洲5在线预测

As current passes through a copper trace its resistance inadvertently heats it up. The local heat transition generates a power that dissipates into the atmosphere by conduction and convection. The designer must calculate the maximum current the trace can carry before it reaches the acceptable temperature rise of about 30°C. A thumb rule in the industry is that the inner layers can sustain only 50% of the current-carrying capacity of the exposed traces.

澳洲5开奖结果大小

Substrate of a PCB is another factor a designer should consider while designing heavy copper boards. Substrate materials range from ordinary FR-4 material with operational temperatures of 130°C to advanced materials with very high glass transition temperatures (Tg). The Tg of the copper and substrate material is very critical since a high current may cause cracks and layer separation.

澳洲5投注

Coefficient of thermal expansion (CTE) is the rate of expansion of a PCB material as it heats up. It is expressed in parts per million (ppm) expanded for every degree Celsius that it is heated to. CTE between copper and the substrate material is also important as thermal stress produced by high currents through traces may result in the formation of cracks, eventually causing board failure.

coefficient-of-thermal-expansion-illustration.gif
A material’s expansion is measured by the CTE. This image shows CTE in the Z direction

Circuit board surface thickness can be elevated through electroplating. It reduces the resistance of copper traces through the improvement of heat conduction. Electroplating is also used by fabricators for PTHs to minimize their thermal resistance. Resistance reduction helps to dissipate heat efficiently through the modes of heat transfer such as conduction, convection, and radiation.

澳洲5软件下载

Sierra Circuits is
headquartered in Silicon Valley.
We welcome visitors at
our 70,000 sqft facility,
located at 1108 West Evelyn Avenue
in Sunnyvale, California.
Book a tour with an account manager today!
Let us introduce you to one of the most innovative communities of engineers and designers in the world.
We can help you plan your project from design to assembled board.

澳洲5历史记录

Our 70,000 sqft state-of-the-art campus in the heart of Silicon Valley contains the most advanced equipment required for the manufacture and assembly of your PCBs. Whether you’re looking for standard quick turn PCBs or boards with the tightest tolerances, made from exotic metals, there’s a reason Sierra Circuits leads the industry in quality and performance.

PCBs manufactured and assembled in the United States

澳洲5开彩结果历史

Sierra Circuits can manufacture your PCB and have it expedited to you within 24 hours.

Full turnkey boards, with assembly and components in as fast as 5 days.


Get an Instant, Itemized Quote

澳洲5龙虎

24 hours a day, 7 days a week.

Call us: +1 (800) 763-7503
Email us: through our Customer Care form

澳洲5预测 极速飞艇网上投注 SG赛车开奖软件 澳洲幸运5全天一期计划