General Purpose Surface

Mounted Resistors

WCR Series

Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com

Issue D · 07.03

Welwyn Components

Construction

The chips have a high alumina substrate (96% minimum) with

a ruthenium oxide resistance element and silver palladium,

nickel and tin plated terminations. A glazed protection coat

is applied to the resistive element (See Fig.1)

Terminations

Solderability

The terminations meet the requirements of

IEC 115-1, Clause 4.17.3.2.

Strength

The terminations meet requirements of

IEC 68.2.21.

Marking

All resistors are individually marked with 3 digits. The first two

digits are the significant figures and the third defines the

number of added zeros. Jumpers are marked 000. Types 0201

and 0402 have no marking.

E96 1% components that can not be marked with 4 digits

will be marked with a standard 3 digit code. Details can be

supplied upon request.

Solvent Resistance

The protective epoxy lacquer and marking are resistant to all

normal industrial cleaning fluids suitable for printed circuits.

Figure 1

Table 1

Packaging

All chips are tape mounted and supplied on standard 8mm

tape reel, as IEC publication 286-3.

180mm (7 inch) reel is standard carries 5,000 pieces.

(Except 0402 carries 10,000 pieces)

250mm (10 inch) reel carrying double the standard quantity

can be supplied by agreement.

Chip Resistor Labstock For Designers

WCR chip resistors are available in a special package of the most

popular sizes containing 50 each of the E24 values.

Please contact the sales desk for full details of this excellent

solution for designers and your prototype build requirements.

Tin Plating

Nickel Barrier

Dipped Conductor

Silver

Palladium

96% min Alumina Substrate

Epoxy Melamine

Glass Dielectric

Resistance Element

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Packaging

All chips are tape mounted and supplied on standard 8mm

tape reel, as IEC publication 286-3.

180mm (7 inch) reel is standard

250mm (10 inch) reel carrying double the standard quantity

can be supplied by agreement.

Chip Resistor Labstock For Designers

WCR chip resistors are available in a special package of the most

popular sizes containing 50 each of the E24 values.

Please contact the sales desk for full details of this excellent

solution for designers and your prototype build requirements.

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