Surface mount devices, Physics

Assignment Help:

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.   


Related Discussions:- Surface mount devices

Energy 2 worksheet , Two pole vaulted clear the bar at the same height. The...

Two pole vaulted clear the bar at the same height. The first lands at a speed of 8.90 m/s and the second lands At a speed of 9m/s the first vaulted clears the bar at a speed of 1

Which atomic model did erwin schrodinger create, Illustrate which atomic mo...

Illustrate which atomic model did Erwin Schrodinger create? Answer:- Schrödinger's wave equation was on the basis of Heisenberg uncertainty principal that the position and

How is quantum theory conceptual view explained, How is quantum theory conc...

How is quantum theory conceptual view explained? Quantum theory gives us with the rules and regulations of the small world. The quantum theory conceptual foundation is mysterio

Work out the voltage, Work out the  voltage for the following arrangement ...

Work out the  voltage for the following arrangement of 1.5V cells: ( Solve problems with cells in series, parallel and series-parallel)

Calculate the final speed of skater - speed and distance, A 50 kilogram ice...

A 50 kilogram ice skater glides across the ice in a straight line at 7 meters per second.  If she bends down and scoops up a 20 kilogram child standing on the ice, what will b

Magnetic materials, Materials which can be magnetized are called magnetic m...

Materials which can be magnetized are called magnetic materials. When magnetized, such materials create a magnetic field around them. Some of the significant features of magnetic m

How is absorption occurred in fibre material, How is absorption occurred in...

How is absorption occurred in fibre material? Absorption is associated to the fibre material. It is caused by three diverse mechanisms, which are: a. Absorption by atomic de

Torque and equilibrium, What is the effect of torque and equilibrium on tap...

What is the effect of torque and equilibrium on taps,handlebars and bicycles?

What are coherent sources, Q. What are coherent sources? Two sources a...

Q. What are coherent sources? Two sources are alleged to be coherent if they emit light waves of the same wave length and start with same phase or have a constant phase differ

Screw gauge, what is screw gauge...? what is the use of screw guage...? how...

what is screw gauge...? what is the use of screw guage...? how make a screw gauge...? what is name of sentince of screw gauge...?

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd