Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Surface Mount Devices (SMDs) are new components designed with soldering pads or short leads. They are much smaller in size as compared to leaded components. The SMDs are directly attached or inserted on the surface of the PCB and then soldered. In the conventional PCB assembly method, the components have leads for insertions into the holes made for the purpose into the boards and are soldered on opposite side of the board. But in surface mount device the components or devices are called surface mount components have leads small then the conventional components which can be soldered on the foot print of the broad directly. In other words in surface mount technology, holes are not drilled and components (specially manufactured) are soldered on the copper side of the board. Chip capacitors, chip resistors, chip inductors are the examples of passive SMDs, while SO-8, So-28, SOT-23 chip carriers are examples of active SMDs. The chip capacitors are multi layer ceramic in value from 1Pf to 1μf or tantalum type with value from 0.22μf to 10μf. The chip resistors are either thick film or thin film type and are available with 1% accuracy. Chip inductors of few mH are available.
ADVANTAGES OF SMDs:
Reduced size and weight. Lower cost. Save lead pre-forming. Components can be maintained from both sides of PCB. Automated high yield production. One machine places most of the components. Smaller production and small area. Smaller size, leadless, low cost. Improved high frequency performance. High dimensions standards. Short interconnections. Better performance. Improved area efficiency. Easy to use computer aided design and manufacture method.
DISADVANTAGES OF SMDs:
Repairs difficult. Generally ultra low power products. Completely new production method and investment. Very high starting costs. New technology, new reliability profile, new problems. Investment in quantity and reliability testing. Difficult to assemble odd shaped components. Must use tape mounted components. Totally new specifications. Needs new manufacturing facilities. Limited power handling. Bread boarding is difficult due to greater power density. PCB heats up. Need new interconnection systems. Unavoidable temperature gradients.
What do you mean by the magnetic moment of a semi circular magnet of radius ‘r' and pole strength ‘m'
what are coherent waves
What are other manufactured wavelengths in Helium-Neon Laser? Then what remembers while there is mention of a He-Ne laser is a red beam, those along with other wavelengths are
what is the methods of dealing with cultural uncertainty is the least successful?
the maximum height attained by a projectile and its horizontal range are equal to each other if the projectile projected at an angle [theta] given by ?
Consider a pentavalent impurity such as phosphorus (P, Z = 15) is doped in a pure semiconductor germanium (Ge, Z = 320. Each phosphorus atom forms four covalent bonds with four ger
Presumptuous that it is understood that the object is in front of the mirror and anything on the other side of the mirror is behind the mirror is the following statement sufficient
a pond is an example of
Describe the construction and working of acousting grating. Construction and Working of Acousting Grating: The liquid is acquired into a glass cell. The Piezo-electric cryst
Advantage and disadvantage of liquid in Glass thermometer
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd