What is a COB chip?
A COB chip is a sort of packaging where several chips are put directly onto a substrate or circuit board without requiring individual encapsulation. COB stands for “Chip on Board.” COB chips typically consist of dozens to hundreds of tiny chips connected in parallel and put on a common metal or ceramic substrate.
Because of their excellent efficiency and power density, COB chips have grown in popularity recently. They are a popular option for various lighting applications since they may offer more light output with less energy use than conventional chips. Furthermore, COB chips are frequently smaller than conventional LED chips. It makes them a viable choice for applications requiring a small form factor.
The Basics of Chip on Board (COB)
A printed circuit board (PCB) is directly mounted with an unpackaged semiconductor chip using the Chip on Board (COB) method, which also requires wire bonding the chip to the PCB. Doing away with the requirement for an external package and lowering the number of interconnects results in a more reliable and compact electronic device.
The COB procedure includes the following steps:
Die Attach: A die-attach machine mounts the semiconductor chip onto the PCB. Then, the chip adheres directly to the Board using conductive adhesive or solder.
Wire Bonding: Little copper, aluminum, or gold-plated wires link the chip to the Board after mounting it. Instead, a wire bonding machine connects the wires.
Encapsulation: We apply a protective resin or epoxy to the wire-bonded chip. It protects against environmental elements like moisture, temperature, and mechanical stress.
The following are only a few advantages of COB technology:
Size and Weight: Because COB technology does not require a separate chip container, electronic products can be made smaller and lighter.
Reliability: COB technology removes the danger of package failure due to temperature cycling, vibration, or mechanical stress by directly connecting the analog chip to the Board.
Cost: COB technology can lower manufacturing costs because it does not require a separate chip package or interconnects.
LED lights, automotive electronics, consumer electronics, and medical equipment frequently employ COB technology.
Differences between LED and COB
LEDs and COBs, two separate lighting technology kinds, are widely used in several applications. However, while they have certain things in common, they also differ significantly from one another.
Chip on Board and Light Emitting Diode both go by the acronym COB. COB is a particular application of LED technology that entails installing several LEDs on a single circuit board. LED is a solid-state lighting technology that uses a semiconductor to produce light. The following are some of the main variations between these two lighting techniques:
Design and construction
The structure of LED and COB lighting is the key distinction. LEDs are tiny semiconductor chips emitting light when exposed to an electric current. Plastic packaging that helps to both protect the semiconductor from the outside elements and offer electrical connections is typically used to house them.
Contrarily, COB lighting entails directly putting several LED chips on a printed circuit board (PCB) and fusing them together via wire bonding. A phosphor film is next applied to the LEDs to create white light.
Light output and intensity
Compared to individual LEDs, COBs often produce light with a higher intensity. This is so that they can produce a focused beam of light due to the tight mounting of the individual LEDs on a COB.
Unlike the LEDs on a COB, which are close together, LEDs typically produce light with a lower intensity. Yet, they can be employed in various applications because they may be produced in various sizes and forms.
Efficiency and energy consumption
Since COBs produce more light with less energy than individual LEDs, they are often more efficient. This is due to the close mounting of the LEDs on a COB. It then lowers the energy lost as heat.
On the other hand, LEDs are less effective than COBs because they produce light of lesser intensity and are not close to each other. Though, they are still more effective than conventional lighting methods like incandescent lights.
Color rendering
In general, COBs are more precise at reproducing colors than individual LEDs. This is so because a COB’s phosphor coating generates a wider light spectrum than a single LED. Because of this, COBs are more suitable for uses like photography and art display, where color fidelity is crucial.
On the other hand, the restricted range of light that LEDs can produce can make it challenging to reproduce colors precisely. However, improvements in LED technology have made it possible to develop LEDs. They can generate a wider spectrum of light, making them more appropriate for uses where color fidelity is crucial.
Price
In general, COBs cost more than individual LEDs. This is because they require more manufacturing processes and resources. After all, they consist of numerous LEDs on a single PCB. Since cost is less of an issue, COBs are better suited for applications where strong light output and color accuracy are crucial.
On the other hand, because they are easier to make and use fewer materials, LEDs are typically less expensive than COBs. This makes LEDs more suitable for lighting in homes or businesses where cost is the main consideration.
What voltage is COB Chip?
A COB (Chip on Board) chip’s voltage might change based on the product’s design. For example, according to the size, power rating, and intended application of the COB, COB LEDs can run at low voltage, typically between 2V to 50V.
The manufacturer’s datasheet offers details on the chip’s electrical properties like the operating voltage, current rating, and power consumption. It contains information on the voltage needs of a COB. Therefore, it is crucial to check the datasheet thoroughly to ensure the COB is compatible with the power supply and other application parts.
A constant current driver, instead of a constant voltage supply, is frequently essential for COBs to function successfully. This is so that a constant current driver can help ensure the COB receives a stable and consistent current. However, a COB’s current draw can vary based on the temperature and other external factors. Because of this, it’s crucial to choose a constant current driver that complies with the voltage and current demands of the COB chip.
COB Chip lifespan
A COB (Chip on Board) chip’s lifespan can vary based on several variables. They include the caliber of the materials used, the environment in which it operates, and the current and voltage levels it faces while in operation.
A high-quality COB chip typically has a lifespan of 50,000 to 100,000 hours or more, substantially longer than that of incandescent or fluorescent lights. As a result, even with constant use, a COB chip can last several years.
The operating temperature can also affect how long a COB lasts because too much heat will shorten the chip’s life. As a result, it’s crucial to ensure the COB properly cools. The operating temperature should stay within the manufacturer-recommended range.
It’s important to remember that a COB chip’s lifespan depends on how long it takes for its lumen output to decline by 70%. The chip may continue to produce light after this, but it will be considerably less bright.
Summary
In conclusion, the choice between LED and COB lighting technologies depends on the application’s particular requirements. Both lighting technologies offer advantages and limitations. While LEDs are ideal for applications where cost is the main consideration, COBs are ideal for those where excellent light output and color accuracy are crucial.
