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1

Application Notes

GENERAL

soldering to printed circuit boards or other substrates. The

construction of the components is such that they will with-

stand the time/temperature profiles used in both wave and

reflow soldering methods.

CIRCUIT BOARD TYPE

(eg. FR-4, G-10).

(eg. FR-4, G-10) and also alumina.

For other circuit board materials, please consult factory.

HANDLING

SMD capacitors should be handled with care to avoid damage

or contamination from perspiration and skin oils. The use of

plastic tipped tweezers or vacuum pick-ups is strongly recom-

mended for individual components. Bulk handling should

ensure that abrasion and mechanical shock are minimized. For

automatic equipment, taped and reeled product gives the

ideal medium for direct presentation to the placement

machine.

COMPONENT PAD DESIGN

Component pads must be designed to achieve good

soldering. Pad designs are given below for both wave and

reflow soldering.

The basis of these designs is:

a. Pad width equal to component width. It is permissible to

decrease this to as low as 85% of component width but

it is not advisable to go below this.

b. Pad overlap 0.5mm beneath large components. Pad

overlap about 0.3mm beneath small components.

c. Pad extension of 0.5mm for reflow of large components

and pad extension about 0.3mm for reflow of small com-

ponents. Pad extension about 1.0mm for wave soldering.

WAVE SOLDERING

1.2

(0.047)

3.1

(0.122)

0.8

(0.031)

0.7

(0.028)

1.2

(0.047)

0.8

(0.031)

2.1

(0.083)

0.55

(0.022)

0.5

(0.020)

0.8

(0.031)

1.06

(0.042)

0.34

(0.013)

0.26

(0.010)

0.40

(0.016)

0.40

(0.016)

3.1

(0.122)

0.8

(0.031)

0.6

(0.024)

1.25

(0.049)

1.25

(0.049)

1.5

(0.059)

1.5

(0.059)

1.0

(0.039)

4.0

(0.157)

1.25

(0.049)

1.5

(0.059)

1.5

(0.059)

2.0

(0.079)

5.0

(0.197)

2.5

(0.098)

0603

0402

0201

0603

0805

1210

REFLOW SOLDERING

0.6

(0.024)

1.7

(0.068)

0.55

(0.022)

0.5

(0.020)

0.6

(0.024)

0.8

(0.031)

2.3

(0.091)

0.6

(0.024)

0.85

(0.033)

0.85

(0.033)

3.0

(0.118)

1.25

(0.049)

1.0

(0.039)

1.0

(0.039)

1.0

(0.039)

2.5

(0.098)

4.0

(0.157)

1.0

(0.039)

2.0

(0.079)

1.0

(0.039)

0402

0.78

(0.030)

0.34

(0.013)

0.26

(0.010)

0.26

(0.010)

0.26

(0.010)

0201

0.8

(0.031)

2.3

(0.091)

0.7

(0.028)

0.8

(0.031)

0.8

(0.031)

0603

0603

0805

1210