Comparison of piranha LED , small straw hat and SMD According to the type of sub package, now on the market there are three main types of cars for LED indoor light design of the LED lamp: piranha LED , small straw hat and SMD. Three package types LED, light-emitting principle is the same in fact, both use a blue light emitting chip, filled with yellow fluorescent powder, blue light by refraction and internal mixing phosphors to produce white light, the external use of epoxy resin, resin have protective chip and prism effect, the angle of the light emitted can be a control.Because the light emitting principle is same, but the brightness is different, to compared the three kind of led. The piranha LED most brightness, in turn is led straw hat and last is SMD. which is the difference between SMD and led straw and brightness.Now To have a practical understanding of the three kinds of LED on the led market with the most.
Fig. 1 piranha LED
Fig. 1 show as piranha LED Piranha LED package is one of the largest in this three types. square, has four legs,is one of the three best package heat dissipation capability.The LED heat through the internal structure(distribution outward from jointing pin) of its own. Piranha LED as bigger in size, the thermal conductivity of metal inside it big, and he has four legs(jointing pin), It is because the Piranha LED has better ability of heat dissipation, his work current of LED is slightly higher than the other two, can reach more than 30mA, while the small straw hat with the normal operating current SMD is about 20mA.In addition,Piranha LED package size is relatively large, it can be integrated in a small reflector inside the package, which is to improve the brightness of Piranha LED is also very good, so the Piranha LED is three packages in a single brightness highest. Another look at a small straw hat (Figure 2) small straw hat LED is circular, looks like a straw hat.
Figure 2 Figure 3
is a small straw hat and a Piranha LED put together photographs, the photos can be seen that small straw hat size is much smaller than the
Piranha LED , no structure reflecting cover, and only two legs(jointing pin), from the structure, thermal performance worse than the Piranha LED , so the small straw working current is lower than the Piranha LED , generally work at about 20mA, so its service life is greatly reduced.Finally, take a look at SMD, SMD is the abbreviation of Surface Mounted Devices, meaning the surface mount device, SMD does not mean a particular LED，it’s just the form of a package, a variety of surface mount components can be called SMD, such as SMD resistors, SMD capacitor, SMD manifold, etc.so the SMD is just a collectively. the same is There are a variety of differences between LED SMD package, for example,such as 0805, 1206, 1210 etc.. So some people say that SMD is a substitute of LED in the future,such a thing is very problematic, because the SMD is just a collectively, how to replace?And now we generally think of the 1210 package
( Figure 4 –some people also known as 3528 to 1210) namely SMD LED, the Piranha LED , a small straw hat with SMD 1210 put together photos.we can see, the SMD LED package size is even smaller than the small straw hat. The greatest advantage of SMD LED package — its small package size in the modern electronic products become smaller, the internal space more and more small, the small size of the components is very competitive. because of its small size,SMD LED because of its small size, meanwhile welding after it is structure of a fully attached to circuit board, so the cooling performance is the worst than the other two, the SMD LED without resin lens, it’s brightness is much lower than the Piranha LED and small straw hat. but then (again), because of the so-called SMD, refers to surface-mount devices, as long as the surface mount, called SMD, so strictly speaking, there are more bright SMD LED, is 1W, 3W or 5W high power SMD LED, shown that some 1W or 3W high power LED as shown in Figure 5 is 1W or 3W power LED , because they are surface-mount packages, so they can be called SMD.
Figure 5
In the above description, we have repeatedly mentioned in one word: radiationPerhaps some people will ask, LED is not known as the cold light source? Not to say that LED does not heat it? We used to have customers get our products after asking us, how does it feels a little hot an open lamp. In fact, When the situation described by the if clause is not presupposed to be false, electronic products all work to be hot, single bright, you might not feel too much heat, but when many LED together, operating at the same time, it comes out of the heat is quite impressive. but relative to the incandescent light bulbs, his fever is much smaller. In the design of LED lighting, heat dissipation design is a very important,because all the LED has a bad light Luminous Flux Depreciation, Luminous Flux Depreciation with LED working temperature is great relationship. so our products in the design of circuit boards, will pay much attention to the heat problem.