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See how EI has innovated a new technology to handle the heat dissipation in PCB. This leads to extended PCB life and safety in overall functioning!!
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Thermal Management
By using PLPCB technology with HEAVY Copper in PCB
PLPCB
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What is PLPCB technology….. PLPCB (PowerLink Printed Circuit Boards) technology allows multiple copper weights �on the PCB for the Buss Bar Application.
“PowerLink”
“PowerLink” is defined as the use of 2 or more copper weights on the same external layer of a printed wiring board.
What is Heavy / Extreme Copper……
�“Heavy Copper” is defined as any circuit with a copper weight in excess of 4oz/ft2 on a printed circuit board.
“Extreme Copper” refers to 10oz/ft2 to 50oz/ft2 (.014” to .07”).�
Why use Heavy Copper?
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Increased mechanical strength at connector sites and plated
holes.
Increase in cross-sectional area of conductors without
increasing trace width or decreasing trace/trace spacing.
Higher current carrying capacity in traces AND in through
holes or vias.
Use of high temperature dielectric materials to their full
potential.
�PowerLink PCB can reduced:
In size reduction.
To protect circuit failure when it’s NOT an option
Reduce number of connectors w/PLPCB.
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Design Considerations
For Heavy Copper and “PowerLink”circuits
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Board Size & Overall Layout
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Board size is limited:
• 1-2 layers, max. board size is 16” x 22”
• 3-14 layers, max. board size is 16” x 22”
Board size is limited by process equipment
Symmetrical construction minimizes bow &
twist
Balanced circuit density minimizes uneven
plating and prevents poor lamination (de-lam)Quality on Time: All the Time
Construction Stack-Up
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Final Thickness is based on the heaviest Copper weights.• Copper thickness (1.4mil / oz)• Final thickness tolerance is +/- 10%
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Maximum Copper thickness in the holes is depending upon the size of the holes.
• Average 3mil of diameter for every oz. of Copper plated to accommodate the heavy copper plating.
Minimum pad diameter := (oz Cu plated x 3) + required drill size + 10 mil
(internal or external layers).
Minimum clearance diameter� := (oz Cu plated x 3) + required drill size + 20 mil
(internal layers)
Holes & Interconnections
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Holes & Interconnections
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• Vias can be plated shut as necessary.
• “PLPCB” requires 1 drill file per copper
weight.
• Non supported holes (NPT with copper
pad)
are not affected by heavy copper.
• Edge plating.
• Plated castellation.Quality on Time: All the Time
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A baseline method of SIZING CONDUCTORS:
• Current, temperature rise and cross-sectional
area.
• Energy generated by the flow of electrical
current
and the resulting power dissipation.
• Use of computer aided thermal analysis; this is
due
to the multitude of factors affecting power
dissipation.
Current Carrying Capacity
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Current Carrying Capacity
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Baseline Calculation
External traces:� I = 0.025 X ΔT 0.45 X W 0.79 X Th 0.53� I= Current in Amps, ΔT = Temp. rise due to power loss,� W= Trace width, Th= Trace thickness�
Internal traces should be derated by 50%�
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Thermal Management
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�Some variables to consider:
• � Environment (exposed to air, space, another
gas)
• Board material properties such as:�• Thermal conductivity�• Material density�• Fluid velocities and viscosities�• Thickness between layers/planes�
• Number of copper planes and their thickness�• Number of plated vias, their diameter and Cu �
weight
• Heat sources other then trace power loss.�Quality on Time: All the Time
Methods of Heat Transfer
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1) Conduction depends on:
- Copper planes and their thickness
2) Convection depends on:
- Fluid Temperature & Velocity, Forced or
natural
3) Radiation depends on:
- Heat sources or sinks
Consider all three when optimizing a designQuality on Time: All the Time
“Built-In” Copper Heat-sinks
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Dissipate heat away from the source
• By conduction and emit this heat to the environment by convection.
• Use of Thermal Dielectric like “Thermal Clad” or “T-Preg” in the heat sinks.
• Use of Heavy copper “Thermal” vias for the heat transfer.
• Use of Heavy copper circuits to create “built-in” copper heat-sinks.
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Why EI?
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The power electronics industry is one of our focus group. We have years of experience developing processes and manufacturing heavy copper circuits. We have …
Aggressive R&D program
Unique manufacturing capabilities:
PLPCB (PowerLink PCB) with multi-copper weights capabilities.
Heavy / Extreme copper tracks and vias.
Edge Plating & Plated Castellations.
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Production Capabilities
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Layer count: 1 - 25
Overall board thickness: 5 - 250 mil
Smallest drilled holes size: 6 mil, (Pad to Hole size may limit
heavy copper, contact us for more detail.
Copper weights:
Outer-layers: up to 50 doz/ft2 (3.12 lbs./ft2)
Inner-layers: up to 8 oz/ft2, with standard processes & up to 90 oz
w/special processing.
�Dielectric Materials:
FR4, Polyimide, BT-epoxy, Cyanate, Ester, High Frequency laminates
– other
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Production Capabilities
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LPI Solder-mask :
• Green, Red, Black in semi-gloss.
Silkscreen Ink:
• LPI White ink (5 mil or larger features)
• Available in : white, black or yellow (8 mil or greater)
Final Finishes:
• Lead Free HASL Solder, HASL PbSn Solder, ENIG, OSP
Electrical testing:
• Net listed (with fixture), flying probe(fixtureless)• Insulation Resistance and HI-POT testing
Production Lot traceability on all partsQuality on Time: All the Time
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Quality on Time: All the Time
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Quality on Time: All the Time
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Quality on Time: All the Time
Quality on Time: All the Time
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Conductor Width, Spacing and Thickness
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• Trace sizing is determined by the current carrying capacity
required and the temperature rise permitted.
• Minimum trace thickness width limited by the
manufacturing process and/or voltage constraints.
• Maximum trace thickness is limited by the line width and/or
spacing.
• A circuit board trace, depending on its size and manufacturing
process, may not be rectangular in shape.
• Additive (plating) processes are preferred to subtractive (etching)
processes but are more expensive. Typical conductor
width/spacing/thickness tolerance is +/- 20%, although tighter
tolerance is achievable.
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Thank You
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