Corporate Responsibility

Environmental Preservation

Ralink is committed to corporate responsibility initiatives, including environmental preservation through appropriate manufacturing processes for all our products. To uphold this commitment, Ralink supports the European Union Directive 2002/95/EC on the Restriction Of Hazardous Substances (RoHS). In addition, Ralink products are free of ozone-depleting substances.

Ralink Supports Restriction of Hazardous Substances (RoHS)

Lead and lead compounds
Cadmium and cadmium compounds
Mercury and mercury compounds
Hexavalent chromium compounds
Chlorinated organic compounds
a. Polychlorinated biphenyls (PCB)
b. Polychlorinated naphthalenes (PCN)
c. Chlorinated paraffins (CP)
d. Other chlorinated organic compounds
Brominated organic compounds
a. Polybrominated biphenyls (PBB)
b. Polybrominated diphenylethers (PBDE)
c. Other brominated organic compounds
Organic tin compounds (Tributyl tin compound, Triphenyl tin compounds)
Asbestos
Azo compounds
Formaldehyde
Polyvinyl chloride (PVC) and PVC blends

Q & A for Ralink lead-free Products

Lead-Free

Q: What is your definition of lead-free?
A: Lead-free is defined as the absence of a significant amount of lead (100PPM for package body and 1000PPM for leads) in a package or part make-up. In an IC package, Pb is commonly found in the external lead finish or plating. In Chip Scale Packages (TFBGA), Pb is found in the Solder Bumps.

Q: What lead-free materials are used to make Ralink products?
A: Material is 100% Matte Tin plating on external leads for EPAD-TQFP, Ni-Pd-Au pre-plating for QFN, and 95.5An/4Ag/0.5Cu for TFBGA.

Q: Do you produce any Non-RoHS compliant products?
A: No.

Q: At what reflow process temperatures are lead-free packages qualified?
A: For all SMD (Surface Mount Devices), qualification is at 260°C peak reflow temperature.

Q: What is the lead-free peak reflow temperature for Ralink Products?
A: 255°C (+5/-0).

Q: Where can I get the Ralink Products reflow profile?
A: Please contact Ralink Sales.

Q: What lead-free reflow profile is recommended?
A: Reflow should follow the lead-free profile in the IPC/JEDEC J-STD-020B specification.

Q: What is the Moisture Sensitivity Level (MSL) for lead-free packages?
A: Level 3.

Q: How would lead-free parts be physically identified or marked?
A: All Ralink products have been lead-free since 2005. Customers can identify them by date codes.

RoHS

Q: Do Ralink Products meet the Directives of both the European Parliament and the Council on the Restriction on Hazardous Substances (RoHS)?
A: Yes.

General

Q: Can lead-free and leaded parts be mixed during board reflow? What reflow temperature would be used in this scenario?
A: Ralink Products lead-free parts can be mixed with leaded parts and reflowed at a lower temperature (235°C) with proper reflow conditions and compatible solder paste.

Q: What are the melting points of solder alloy and its pure components?
A: Melting points are as follows:

Element/Alloy         Melting point (liquids)
Pure Lead              328° C
Pure Tin                 232° C
63Sn/37Pb             183° C
95.5Sn/4Ag/0.5Cu   217° C

Calculations

Q: How do you calculate chemical level in parts per million?
A: Take the weight of the constituent (i.e. lead) and divide by the unit weight. Multiply the outcome by 1,000,000. For example: the weight of lead in the part is 0.000375 grams and the unit weight is 0.1473 grams, therefore ppm = 0.000375 / .1473 x 1,000,000 = 2546 ppm

Q: How do you calculate chemical level as % of the constituent by weight?
A: Take the weight of the constituent (i.e. lead) and divide by the unit weight. For example: the weight of lead in the part is 0.000375 grams and the unit weight is 0.1473 grams, therefore % = 0.000375 / 0.1473 = 0.002546 x 100 = 0.2546%.

Tin Whiskers

Q: Have you tested for Tin whiskers? Describe qualification tests performed.
A: Tin whiskers are tested during package qualification at the assembly site. Tests performed are:

TCT(air to air), -55+0/-10°C~ 85+10/-0°C, 20C/min ramp rate & 10 min dwell, 1K cycles
Storage, 60+/-5°C, 93+/-3%RH, 2000 hr
Storage, Room atmosphere (30+/-2°C, 60+/-3%RH), 2000 hr

Q: What is the acceptance criteria for Tin whiskers qualification? What is the method of identifying Tin whiskers?
A: Less than 50um in any dimension of whiskers is considered acceptable. Visual inspection is performed under SEM. There is currently no JEDEC/IPC standard for Tin whiskers testing; inspection and acceptance criteria follows NEMI recommendation.

Q: What regular monitor and assembly process controls are in place for Tin whiskers?
A: Tin whiskers are controlled and monitored in assembly by:

Visual inspection at 30X magnification. Frequency of 2X/shift, Sample size = 10 strips.
Plating bath analysis once a day for Tin, acids and bath organic content.