28

SMD Thin-Film Fuse

QUALITY & RELIABILITY

thin-film technology and materials used in the semiconduc-

tor industry.

• In-line Process Control: This program forms an integral

part of the production cycle and acts as a feedback sys-

tem to regulate and control production processes. The

test procedures, which are integrated into the production

process, were developed after long research and are

based on the highly developed semiconductor industry

test procedures and equipment. These measures help

AVX/Kyocera to produce a consistent and high yield line

of products.

• Final Quality Inspection: Finished parts are tested for

standard electrical parameters and visual/mechanical

characteristics. Each production lot is 100% evaluated for

electrical resistance. In addition, each production lot is

evaluated on a sample basis for:

• Insulation resistance (post fusing)

• Blow time for 2 x rated current

• Endurance test: 125°C, rated current, 4 hours

HANDLING AND SOLDERING

SMD chips 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

recommended for individual components. Bulk handling

should ensure that abrasion and mechanical shock are

minimized. For automatic equipment, taped and reeled

product is the ideal medium for direct presentation to the

placement machine.

CIRCUIT BOARD TYPE

All

flexible

types

of

circuit

boards

may

be

used

(e.g. FR-4, G-10).

For other circuit board materials, please consult factory.

COMPONENT PAD DESIGN

Component pads must be designed to achieve good joints

and minimize component movement during soldering.

Pad designs are given below for both wave and reflow

soldering.

The basis of these designs are:

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.

c. Pad extension 0.5mm for reflow. Pad extension about

1.0mm for wave soldering.

PREHEAT & SOLDERING

The rate of preheat in production should not exceed

4°C/second. It is recommended not to exceed 2°C/

second.

Temperature differential from preheat to soldering should

not exceed 150°C.

For further specific application or process advice, please

consult AVX.

HAND SOLDERING & REWORK

Hand soldering is permissible. Preheat of the PCB to 100°C

is required. The most preferable technique is to use hot air

soldering tools. Where a soldering iron is used, a tempera-

ture controlled model not exceeding 30 watts should be

used and set to not more than 260°C. Maximum allowed

time at temperature is 1 minute.

COOLING

After soldering, the assembly should preferably be allowed

to cool naturally. In the event of assisted cooling, similar

conditions to those recommended for preheating should

be used.

REFLOW SOLDERING

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)

1.0

(0.039)

1.0

(0.039)

2.0

(0.079)

4.0

(0.157)

1.6

(0.063)

WAVE SOLDERING

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)

1.6

(0.063)

1.25

(0.049)

0.6 (0.024)

1.25

(0.049)

3.1

(0.122)

3.1

(0.122)

0.85

(0.033)

0.6 (0.024)

0.85

(0.033)

2.3

(0.091)

3.1

(0.122)

1206

0612

0805

0603

0402

0402

1206

0612

0805

0603

0.8

(0.031)

0.8

(0.031)

0.5

(0.020)

2.1

(0.083)

0.59

(0.023)

0.6

(0.024)

0.6

(0.024)

0.5

(0.020)

1.7

(0.068)

0.59

(0.023)