At the conclusion of our webinar, How to Properly Size and Select Your Custom Flexible Heater, we had several questions submitted to our presenter, User Interface & Cable Assembly Product Manager, Steven J. Goodman. We compiled these into a readable format on our blog.
Q&A From Our Live Webinar
Quick Links:
- What's the highest wattage heater you can make?
- Are there limitations for shapes that you can make?
- Can you embed a heater circuit in a PCB?
- Is there such a thing as a double-sided heater?
- What are the standard lead times, and are there additional lead times for non-standard items?
- Are there typical connectors or other typical connectors that are compatible with your power source?
Watch the Recording Below:
Question: What's the highest wattage heater you can make?
Answer: I know the size limitation is what's going to be the issue here, and it's more the watt density. As long as our watt density is below 10 or 20 watts per square inch, and you can provide enough voltage to drive the heater, we can make it as long as you need. The key there is we would need to understand the overall length, the voltage and wattage requirements, and then make sure that we have an opportunity to build some samples first to make sure that our solution meets what you're trying to do. But there really isn't a highest wattage heater because as much energy as you can dump into it, you hope that you can dissipate that.
Question: Are there limitations for shapes that you can make?
Answer: No, because these are completely custom and built from scratch. And what I mean is we're either die-cutting or laser-cutting these. So, the shape, the perimeter shape of the heater, as long as it's something you can define, either through a DXF or some other CAD program, we can produce that. There are some limitations on the width. Anything that's going to be thinner than about a quarter of an inch or so is probably too small. We need to give ourselves room to park one or two traces and have enough edge distance to seal the film, whether it's polyimide or silicone. So, the answer is that there are really no limitations on the shape, as long as it's something that you can define in CAD or in another drawing.
Question: Can you embed a heater circuit in a PCB?
Answer: While yes, we can embed “a heater” in a rigid PCB, this is not common for us.
Question: Is there such a thing as a double-sided heater?
Answer: This is a good one. I've actually never thought about this. But the answer is that all heaters are double-sided. It's just a heating element with film on both sides. So, in theory, the heater is double-sided. The key is that some customers only put an adhesive on one side and affix the adhesive to another member on that one side. But there are situations where we've seen customers that will take a heater and sandwich it in between two plates so that the heat goes in both directions.
Question: What are the standard lead times, and are there additional lead times for non-standard items?
Answer: Our typical manufacturing time is about 15 business days. That's for material that we have and use and already building with. If a given application needs an extremely high temperature adhesive or a potentially low outgassing type of polyimide, or maybe there's a specialty connector of some sort, our lead time is driven by whatever is on the critical path for that heater. Typically, if there's a long lead or high-risk item that we're looking at, we'll work with our customers to flag that, to communicate what's driving our lead time, and to have a discussion to see if there are options that we can consider to give us an equivalent or another type of design that's something we can get sooner, pulling in that lead time.
Question: Are there typical connectors or other typical connectors that are compatible with your power source?
Answer: I believe the best way to answer that is that most customers just want flying leads, two wires that are stripped and tinned, and then our customers do whatever they need to do, whether it's soldering those wires to another board or potentially crimping and terminating them. But there really are no standard connectors. It's any type of power connector that you need that can handle the voltage and current for the given application. Some of these heaters will draw high amounts of current, so we need to make certain that whatever terminal and connector we are selecting will survive whatever current and voltage requirements the heater may have.
Key Takeaways
- No hard wattage limit, but watt density matters: Flexible heaters can be built to very high wattages, but the key constraint is staying within safe watt density levels (typically under 10–20 W/in²) and ensuring voltage and dissipation requirements are met.
- Shapes are highly customizable: Flexible heaters can be die-cut or laser-cut into almost any CAD-defined shape, with only minor limitations on extremely narrow widths.
- Heaters can be embedded or double-sided: While embedding heating circuits in PCBs is uncommon, it is possible. By design, all heaters are technically “double-sided,” and heat can be directed or sandwiched between surfaces depending on application needs.
- Lead times vary with material and component choices: Standard heaters typically ship in 15 business days, but specialty adhesives, high-temp films, or unique connectors may extend lead times. Customers are advised to review critical-path items early.
- Connector options are application-driven: Most customers prefer simple flying leads, but nearly any power connector can be integrated as long as it can safely handle the heater’s voltage and current requirements.
