LEDs
Light emitting diodes, These are electronic components that produce
light by conversion of electrical energy directly to light by the
movement of electrons within the material of the diode. They are
important because due to their efficiency and low energy, they are
beginning to replace most conventional light sources.
The P-N junction is the basis of the functioning of the LED. The LED
has an anode and a cathode separated by a crystal of semiconductor
material. Addition of impurities to the semiconductor material produces
P-N junctions within the chip. The entire assembly is housed within a
plastic cover that can also double up as a lens to guide the light
emitted by the LED.
Various Type Of
LED Technology:
1-
DIP Chip (Dual In – Line Package ):
The Direct In-line Package (DIP) module is assembled from three separate
colors of the more archetypal, bubble-shaped LED with two connector
feet. The diodes are stamped into a pre-drilled Printed Circuit Board
(PCB) using a process knownas “through-hole” mounting. The legs are
then soldered onto pads on the opposite side, which can be done by hand
or with machines. DIP modules are typically used for outdoor
applications, because having separate, encapsulated diodes makes them
better at dispersing heat and more weather resistant than SMD modules.
Surface mount diodes are typically used for smaller pixel pitches in indoor applications. The largest SMD module typically seen is a 6mm pixel pitch, and it can be made to sizes of 4mm and smaller.
As technology advances and the precision of machinery increases, these new modules are not only becoming more affordable, but are seeing a longer working life-span, and are becoming more reliable.
In a number of applications from mobile devices to indicator lights, SMD LEDs have clearly replaced DIP modules. They are, however, not poised to dominate the outdoor digital signage industry for a handful of reasons
2-
SMD Chip ( Surface Mounted Diode ) :
This is a better technology that the
first generation DIPS The SMD type are mounted on an aluminum substrate
and enveloped in an epoxy resin. SMD LED stands for surface mount LED.
Specifically, it's a light-emitting diode that is mounted onto and soldered
onto a circuit board. An SMD LED is quite small since it has no leads or
surrounding packaging that comes with a standard LED. This means it's best
handled, not by a human, but by automated assembly equipment. An SMD LED also
has a wide viewing angle, thanks to the fact that it does not have the standard
LED's epoxy enclosure that focuses the beam.
LED strip lighting can be manufactured
with a variety of LED chips. The numbers you see such as 3528 and 5050 refer
to the size of the chip. The older style strips that have been popular for
a few years now are the sizes seen above. Currently, there are even smaller and
more efficient LED chips on the market with the sizes of 2835, 3014, 5630, and
3020.
The LED chips are called SMD 5050 because
the dimensions of the chips are 5.0mm x 5.0mm. They have 3 LED diodes
in one housing (sometimes called tri-chips), and are a lot brighter than
individual 3528 LED chips. They are used when you need high illumination for
your project area and especially RGB color changing lights.
Theoretically, SMD 5050 LEDs can offer a light output 3 times that of
the 3528 strips, and therefore the 5050 LED is well suited for lighting up
areas that may be subject to high levels of ambient light. However, since they
are larger in size, there are only so many you can fit onto the PCB. There are
some brightness restraints when using the 5050s in this way. Though they
produce more heat than smaller chips, it is still drastically lower than other
lighting options. These types of LEDs require a thicker PCB to draw the heat
away from the chips. The 5050's are different from the 3528 LEDs in that
5050s can combine the three different chips to inside the housing to create
millions of color variations. While
the 5050 chip can be used in single color applications, we have found the 5050
LEDs to be better for the RGB and the 3528 SMD LEDs in high density better for
single color applications.
The chips called SMD3528 because the
dimension of the chip is 3.5mm * 2.8mm. These LED chips (one LED per
chip) are bright but not as bright as the 5050 side by side but when used in
higher quantity can be brighter than a compatible strip of 5050s. These lights
are great for TV backlighting, color splashing walls, accent lighting for crown
molding and pictures, under tables and cabinets, bars, etc. 3528 LEDs can be most
cost effective, but will not be as bright when compared individually to a 5050
chip, but when there are 600 of them on a reel, they can be brighter than a
5050 strip.
Pay attention to how many LEDs there are
per foot or meter. When searching for a bright LED strip light, make sure you
compare apples to apples and look for how many LEDs are offered on the
product.
Other sizes: 3020 LED chips and 3014 LEDs
in high brightness LED strip lights.
Though 5050 and 3528 SMD LEDs were the
most popular on the market for strip lights, the LED market has changed rapidly
over the past few years.
Today, there are other LED chips
available that are brighter and also more efficient. The 3020 SMD LED
chips in our High CRI Ultra Bright and 3014 SMD LED chips in our Architectural Ultra Bright and Design Series
Ultra Bright LED strip lights are smaller and more efficient than their
predecessors. Because the LED sizes are much smaller, we were able to fit many
more of them onto the strip lights, thus creating blindingly bright LED strips.
3-
COB Chip ( Chips On Board ):
The most recent LED development has been “Chip On Board” or COB technology. COB and SMD can be similar because like SMD, COB chips have multiple diodes on the same “wafer” or chip. However, this is where the similarities end. In fact, on every COB chip there are multiple diodes; typically 9 or more. The other big difference between COB and SMD technology lies in the fact that while SMD requires a circuit for every diode included on the chip, COB devices only have 1 circuit and 2 contacts for the entire chip regardless of the number of diodes. This single circuit design, regardless of the number of diodes on the chip, leads to simplicity for the rest of any COB LED device. Perhaps even more important than the simplicity aspect, COB also leads to improved lumen-per-watt ratios in comparison to other LED technologies such as DIP and SMD. Unfortunately, the big draw back from the single circuit design of COB chips stems from the fact that multiple channels are necessary to adjust individual levels of light output to create color changing effects. What this basically means is that COB technology, while very powerful and efficient in single-color applications, cannot be used to create color changing bulbs or lights.
Before COB technology, LED spot lights and flood lights were historically considered “non-standard lamps” because they required multiple LED sources to produce a high lumen output. Since the advent of COB chips in the LED arena, a large lumen count can be produced from a single source using a COB chip. This was never possible before COB, but has been a revolution for people who want to lower their energy bill but also need a standard lamp. Besides spot lights and floodlights, COB chips have been put into all kinds of bulbs and used for a number of other applications as well. In fact, COB technology is used for any small device with a flash such as a Smartphone or camera. The principle is that COB chips produces a large amount of lumens for very little energy, which is very important for any device that runs on a battery. Many Smartphones have a small 2×2 or 3×3 COB matrix to produce their camera flash. Point-and-shoot cameras similarly support a small COB chip that will use little energy and produce a large amount of light.
COB chips vary widely in their applications and thus different chips will require different wattage, voltage, and will produce vastly different lumen counts. However, it can be said of COB chips that the ratio of lumens per watt is very high, typically 80 lumens per watt minimum to well over 1oo lumen per watt.
The most recent LED development has been “Chip On Board” or COB technology. COB and SMD can be similar because like SMD, COB chips have multiple diodes on the same “wafer” or chip. However, this is where the similarities end. In fact, on every COB chip there are multiple diodes; typically 9 or more. The other big difference between COB and SMD technology lies in the fact that while SMD requires a circuit for every diode included on the chip, COB devices only have 1 circuit and 2 contacts for the entire chip regardless of the number of diodes. This single circuit design, regardless of the number of diodes on the chip, leads to simplicity for the rest of any COB LED device. Perhaps even more important than the simplicity aspect, COB also leads to improved lumen-per-watt ratios in comparison to other LED technologies such as DIP and SMD. Unfortunately, the big draw back from the single circuit design of COB chips stems from the fact that multiple channels are necessary to adjust individual levels of light output to create color changing effects. What this basically means is that COB technology, while very powerful and efficient in single-color applications, cannot be used to create color changing bulbs or lights.
Before COB technology, LED spot lights and flood lights were historically considered “non-standard lamps” because they required multiple LED sources to produce a high lumen output. Since the advent of COB chips in the LED arena, a large lumen count can be produced from a single source using a COB chip. This was never possible before COB, but has been a revolution for people who want to lower their energy bill but also need a standard lamp. Besides spot lights and floodlights, COB chips have been put into all kinds of bulbs and used for a number of other applications as well. In fact, COB technology is used for any small device with a flash such as a Smartphone or camera. The principle is that COB chips produces a large amount of lumens for very little energy, which is very important for any device that runs on a battery. Many Smartphones have a small 2×2 or 3×3 COB matrix to produce their camera flash. Point-and-shoot cameras similarly support a small COB chip that will use little energy and produce a large amount of light.
COB chips vary widely in their applications and thus different chips will require different wattage, voltage, and will produce vastly different lumen counts. However, it can be said of COB chips that the ratio of lumens per watt is very high, typically 80 lumens per watt minimum to well over 1oo lumen per watt.
4-
MCOB Chip ( Multiple Chips On Board ):
Since the creation of COB chips, a variant has come along called MCOB or “Multiple Chip On Board”. MCOB devices are very similar to COB chips in their application and are more or less just multiple COB chips together in series. MCOB devices differ from COB because they are better for low wattage situations. They also do not fulfill the standard lamp requirement for spot light and floodlights, as mentioned earlier in the COB section of this post. While MCOB devices do not meet the requirements to become a standard lamp, they produce a lot of light and are great for low wattage situations like A19 bulbs. In fact, A19 bulbs are currently the most common use of MCOB technology. If you buy an LED A19 bulb in the near future, it will likely be an MCOB bulb.
5-
MCMCOB Chip ( Multiple Chips and Cups on Board ):
The MCM technologies can be divide into the following 3 main areas depending on the type of substrate used:
· MCM-C
· MCM-D
· MCM-L
C, D and L defines the substrate type of the MCM where MCM - L is the Multi Chip Module Laminate Substrate, MCM - C is the Multi Chip Module Ceramic Substrate and MCM - D is the Multi Chip Module Thin Film Substrate
A Multi Chip Module (MCM) is an electronic system or
subsystem with two or more bare integrated circuits (bare die) or Chip Sized
Packages (CSP) assembled on a substrate. The substrate is either a PCB, a thick/thin
film ceramic or silicon with an interconnection pattern. The substrate is
either an integral part of the package or will be mounted in a package. The
package can be a standardized package containing parts of the electronics for
assembly on a printed circuit board or a package containing all the
electronics. The full module can be assembled directly in the system (PC,
instrument or mechanical design, etc.). Multi chip Modules introduce a packaging
level between ASICs and PCBs and there are many reasons why this might be
beneficial. The driving forces to develop an MCM instead of using packaged
circuits, assembled on a printed circuit board (PCB) are:
Size: The utilization of the active silicon area is
about 15% for surface mounted circuits on a PCB. In an MCM it can be between
30-60% or even higher
Description of MCM Technologies
The MCM technologies can be divide into the following 3 main areas depending on the type of substrate used:
· MCM-C
· MCM-D
· MCM-L
C, D and L defines the substrate type of the MCM where MCM - L is the Multi Chip Module Laminate Substrate, MCM - C is the Multi Chip Module Ceramic Substrate and MCM - D is the Multi Chip Module Thin Film Substrate
0 Blogger