CircuitSeal™ is the process of hermetically sealing and encapsulating connectors and electronic circuits within a low-outgassing, chemically inert hermetic epoxy.

By encapsulating the circuit board, connector, or flex circuit, customers have increased design flexibility to design a small, lightweight electronic package. CircuitSeal can integrate a variety of circuit board and electrical connection types including flex, rigid, hybrid and flat flex cable (FFC). Douglas encapsulates customer electronics and circuits to protect against corrosion and electrical shorts caused by water vapor and condensation or creates a hermetic barrier between the circuit and housing assembly or enclosure.

Non-hermetic connectors offer more design options and are lower cost than their hermetic counterparts. Douglas Electrical can hermetically seal a non-hermetic connector and directly integrate it into the circuit board or flex circuit offering a moisture tight seal as well as connector headers and receptacles. CircuitSeal hermetic packages create cost-effective solutions be enabling customers to use smaller mechanical packages to protect electronics.

The mechanical interface can also be customized to simply sit on a hermetic circuit or integrate a housing such as a radial O-ring, jamnut, or bulkhead housing. This adds design flexibility to not only seal the circuit but the mechanical interface that the circuit is designed within including control boxes, housings, and custom assemblies. Our epoxy and the mechanical assemblies can be designed for both vacuum and positive pressure and a wide temperature range.

Hermetically sealed circuit boards are useful for enclosure projects with complex computations as well as sensors, switches, diodes, and capacitors. Potting and sealing effectively blocks and seals against contamination due to outgassing. This hermetic seal technology is also trusted in flexible circuit board connectors and their applications along with hermetic bulkhead applications that require lightweight, compact sealing methods for feedthroughs like missiles, bomb fuses, or even batteries.

Douglas Electrical Components also offers a hermetic back-potted connectors and sealed connector assemblies for applications where only the connector requires hermetic sealing with connection via pins, wires, or cable. Hermetic bulkhead connectors are also available through our PotCon series.

Features

FEATURES

• Hermetically seal circuits, sensing elements, fuses, and filters in a compact, chemically inert package
• Improved mechanical and electrical performance and reliability while reducing connection points
• Integrate any of our electrical connection types including MIL-spec connectors to create a hermetic assembly
• Use the design you have or start over – Douglas will partner with you to hermetically seal the circuit within the existing layout or partner to find a better alternative

ADVANTAGES

• Protect against water vapor, condensation, and contaminants
• Low profile assembly
• Meets various MIL-spec standards for moisture resistance
• Chemically inert epoxy
• Hermetically seals to various materials
• Increase conductor density through the hermetic seal
• Design for harsh environments and hazardous locations
• Maintains signal integrity, eliminates electrical noise (EMI), and reduces failure points.
• High conductor density in smaller, sealed assembly (30-70% smaller).
• Hermetically seals components for vacuum system integrity.
• Integrates and seals conductors, reducing labor and costs (up to 80% savings).

KEY CAPABILITIES

• Flex, rigid, hybrid and flat flex cable (FFC) styles
• Suitable for applications with space or weight constraints
• Allows for easy use of active and passive signal conditioning at the glove box bulkhead

COMMON HERMETIC CONNECTION TYPES

• Flat Flex Cable (FFC)
• Printed Circuit Board (PCB / PCBA)
• Pogo Pin Feedthroughs
• Terminal Headers
• Connector Back-potting
• Hybrid / combination designs

MARKET CAPABILITIES

• ISO 9001:2015
• ISO 14001:2015
• RoHS / REACH compliance
• ITAR DDTC Registration
• Meet various sealing standards and testing methods within MIL-STD-883 MIL-STD-750

FAQ

What is CircuitSeal?

CircuitSeal addresses key challenges in designing underground electrical equipment and sealed devices by improving performance, reducing size, and cutting costs. It creates direct hermetic seals around circuit boards and cables, integrating passive components like filters and resistors. Ideal for reliable operation in pressurized, vacuum, and harsh environments.

CircuitSeal can play an important role in applications like semiconductor manufacturing, automotive systems, magnetic bearings, environmental chambers, and military systems.

What are some applications where I would need a hermetic pcb connector?

CircuitSeal is a rather broad product line in terms of application use, which speaks to its flexibility. For example, a CircuitSeal pcb connector could be integrated into a LiDAR or camera assembly where the customer needs to ensure it is hermetically sealed to prevent moisture ingress over time. In military applications where an engineer is looking to reduce weight / payload, a hermetic connector assembly could create the interface between a flex circuit and existing harness. Automotive applications can require hermetics within sensor assemblies to survive direct media contact as well as submersion within a fluid such as transmission fluid.

Can CircuitSeal hermetic connector assemblies be used in pressurized applications?

Yes, Douglas Electrical can partner with you for both vacuum and pressurized applications. When contacting us, please share the operating pressures and differential pressures you expect. Additionally, operating temperature will be a critical factor in the design

What are the advantages of an epoxy-based potting solution over a traditional glass-to-metal seal?

Design flexibility is a key differentiator for epoxy-based solutions; standard electrical connections can be enhanced as a hermetic connection with minimal tooling and setup capability. Relying on standard, off-the-shelf designs allows design flexibility to stay fiscally responsible and maintain the ratings of the existing design. Smaller production volumes are traditionally easier and faster with epoxy-based designs, whereas glass-to-metal designs require setups and tooling.

For electronic encapsulation, epoxy can be applied directly to the flex circuit or wires and hermetically seal. Glass-t0-metal seals require a high temperature process to fire the pins to the metal housing. Thus, the assembly will need to be separately connected to the hermetic glass-to-metal seal.

To learn more about the differences between glass-to-metal and epoxy seals, download our whitepaper. Types of Hermetic Seals

How does potting encapsulate the electrical connection?

Douglas Electrical Components uses a variety of proprietary steps to ensure the right potting compound, process, and materials are used to ensure encapsulation of the electrical connection. CircuitSeal can reduce the number of electrical connection points, decrease assembly weight, and increase reliability by encapsulating the most critical electronics, from missiles to sensors to batteries.

Does Douglas offer connectorized flex circuit assemblies?

Yes, a connectorized flex circuit assembly is a simple way to create a high density hermetic assembly. Douglas can integrate rigid and flexible circuits into a hermetic package. The flex or rigid circuit can directly interface with the connector receptacle or to an interface circuit board.

Is CircuitSeal available for rigid circuit boards?

Yes, CircuitSeal can add hermetic, moisture-tight sealing to a rigid circuit board. This includes existing circuit board designs that need enhanced protection in harsh environments or new product development.

Does Douglas sell the epoxy as a standalone item?

No, we do not sell the epoxy; we manufacture the pre-potted assembly. Aside from the proprietary nature to our epoxy, we also employ special techniques and processes to ensure the hermetic seal. This comes with decades of product and application experience in various areas. Our team is easy to partner with, thus working through the design process and creating a “design for manufacturing” assembly that meets your hermetic and liquid-tight sealing needs at virtually any electrical connection.