Selecting the optimal copper weight is a crucial decision in PCB design. Copper weight, typically measured in ounces per square foot (oz), directly impacts performance, current capacity, and thermal properties. Here, we compare 1 oz vs 2 oz copper PCBs, exploring the implications of each.
What is a 1 oz Copper PCB?
A 1 oz PCB features 1 ounce copper with a thickness of 1.37 mils or 34.79 microns. This is a standard copper weight for rigid PCBs, ensuring efficient conduction while maintaining resistance. 1 oz copper PCBs utilize tin alloys to maintain the desired 1 oz thickness. They also employ flame retardant materials for safety and reliability.
1 oz copper PCBs typically use epoxy resins and PTFE. The 1 oz copper layer is present on each thin PCB layer. If specs do not indicate otherwise, PCB manufacturers will default to 1 oz finished copper weight.
What is a 2 oz Copper PCB?
A 2 oz copper PCB has a thickness of 2.8 mils or 70 microns. It serves as the standard copper weight for internal and external PCB layers with a 3 oz finished weight. 2 oz copper enables improved layer arrangements, especially for outer PCB layers.
In PCBs, 2 oz copper offers many benefits, including enhanced reliability, stability, and compatibility with etched PCBs. For standard internal layers, 2 oz PCBs adhere to 70μm thickness. This is commonly used as the starting point for 3 oz finished boards.
While more common in rigid PCBs, 2 oz copper is gaining traction in flexible PCBs, despite the prevalence of lighter 0.5 oz and 1 oz weights. However, heavier copper weights like 2 oz must be evaluated against flexibility needs.
Comparing 1 oz vs 2 oz Copper PCBs
Here is a detailed comparison of key differences between 1 oz and 2 oz copper PCBs:
- Copper Weight: 1 oz is 1.4 mil/35 μm, 2 oz is 2.8 mil/70 μm
- Thickness Range: Both offer standard 0.062” or custom
- Current Capacity: 1 oz has lower, 2 oz has higher
- Heat Dissipation: 1 oz is moderate, 2 oz is improved
- Voltage Drop: 1 oz has higher, 2 oz has lower
- Thermal Conductivity: 1 oz is lower, 2 oz is higher
- Cost: 1 oz is lower, 2 oz is higher
- Applications: 1 oz for low power, 2 oz for high power
Choosing 1 oz vs 2 oz Copper
There are two key considerations for optimal PCB copper thickness:
- Current capacity for acceptable heat rise
- Mechanical strength based on thickness, holes, and vias
Some key points include:
- Evaluate circuit current needs. Higher current requires 2 oz.
- Consider thermal management. 2 oz better dissipates heat.
- Assess voltage drop tolerance. 2 oz has lower drop.
- Check space constraints. 2 oz needs more space.
- Discuss manufacturing capabilities and costs.
- Weigh cost against specific benefits of thickness.
- Match to demands of application. 2 oz suits high power.
Get Quality 1 oz or 2 oz PCBs
At VictoryPCB, we deliver high-quality, tailored PCBs to meet unique client needs. With extensive experience and advanced manufacturing, we guide you in choosing between 1 oz vs 2 oz copper PCBs. Contact us at sales@victorypcb.com to partner with a PCB manufacturer who understands copper weights and provides tailored, high-quality PCBs. Let us help bring your designs to life.