Frequently Asked Questions and Support - Samtec

Connector Selection

How does one go about selecting a connector that is sufficient for their design?

Items to be considered include connector performance, routing efficiency, and pin density. For more information, contact our Signal Integrity Support.

Link to RHT

How do we address the question, “Will this connector work in my design”?

The following information about your application will help determine if a connector system can meet the signal integrity requirements:

• System Topology: point-to-point, multi-drop, point-to-many-point, Star, etc
• Termination Type: Parallel (one/both ends), Products, Active, RC, none
• Clocking/Data Recovery: synchronous, asynchronous, source synchronous, CDR
• Signaling Type: Single-Ended or Differential
• Data Encoding: Binary, PAM-2, PAM-4, etc
• Signal Technology: examples include LVTTL, SSTL-2, Rambus, LVDS, PECL, CMOS, GTL+
• Signal Data Rate: specified in Mbps or Gbps
• Signal Edge Rate: specify 10/90 or 20/80
• System Impedance: specified in ohms along with tolerance (e.g., +/- 10%)
• Crosstalk Requirements: specified at receiver (in % of voltage swing or dB)
• Skew to make educated recommendations

For more information, contact our Signal Integrity Support.

Does the stack height of the connector make a difference in its speed?

Always choose the shortest connector that can do the job. The shorter the connector, the shorter period of time for reflections and crosstalk to act, and the better the signal quality. For more information, contact our Signal Integrity Support.

What is the optimal signal-to-ground ratio?

A signal-to-ground ratio of 1:1 is usually optimal, but for connectors with large pin arrays signal-to-ground rations of less than 1:1 may be required for reliable high speed single-ended operation. For more information, contact our Signal Integrity Support.

Are there any recommendations for the best performance when using high speed differential connectors?

For differential connectors running at 2.5 Gbps and above, ground shielding of the pairs can be very beneficial. For more information, contact our Signal Integrity Support.

Does a connector have one impedance?

No. A connector’s impedance profile changes with respect to change in signal-to-ground ratio. The “exposure” of the impedance discontinuities within the connector is dependent on the edge/fall rate of the signal propagating through the connector.

Does a connector’s impedance profile change relative to system impedance changes?

No. The impedance discontinuities inherent to the connector’s design are independent of the characteristic system impedance.

Can I use your high speed connectors to distribute power?

Yes. Here are some guidelines for assigning pins for power distribution:

• If the connector has ground blades (e.g., Q-products) that are used to distribute power through the connector, and the connector is used for high-speed signaling, then the following should be done: All signals passing through that section of the connector should be referenced to the same power plane being passed through the connector on both sides of the board, OR if referenced to ground, the power plane should be adjacent and close to the ground plane on both PCBs. This recommendation will ensure that the signal return path is unbroken across the connectors, increasing bandwidth and decreasing EMI.
• If signal pins are used to distribute power through the connector, they should be placed considering the noise which can occur due to signal coupling. Signal pins passing power and ground are as susceptible to noise as any signal pin would be. Sensitive power signals should be well isolated with grounds on either side to reduce crosstalk. And for low noise power, such as a precision voltage reference, it may be necessary to isolate the power pin with multiple grounds on either side, and on the back side of the connector.

Does Samtec have on-line Signal Integrity Resources?

Check out the Samtec Blog for the latest Signal Integrity Resources from the Samtec gEEk blogging team. We’re working daily to populate the blog with the kind of great Samtec content you have come to know.

Electromagnetic Modeling

What types of connector model structures does Samtec offer?

Samtec offers single-line and multi-line structures. The models represent MATED connectors (male and female connectors or card edge connector with edge card inserted).

How do single-line models (SLM) differ from multi-line models (MLM)?

The SLM is used to evaluate the effects of a single set of connector pins. A SLM is independent of connector wiring pattern and is an approximation of a well referenced connector. The MLM differs from a SLM in that it accounts for the electrostatic and electromagnetic coupling, as well as the common impedance noise found in a connector. Its structure couples in three dimensions all pins to each other. This results in a complex model that uses product resistance, inductance,coupling capacitance and inductive coupling coefficients so arranged to allow connections at both the input and output. This modeling effectively shows the coupled noise. This is done, though, at the expense of CPU runtime.

What type of analysis can I do with a Single-Line Model?

Single-Line models can be used to analyze: Propagation delay, Attenuation, Reflections, Drive power, Timing. A SLM CAN NOT BE USED TO EVALUATE CROSSTALK! (FOR CROSSTALK - A MULTI-LINE MODEL MUST BE USED.)

What type of analysis can I do with a Multi-Line Model?

Multi-Line models can be used to analyze: Propagation delay, Attenuation, Reflections, Drive power, Timing, Electrostatic coupling, Electromagnetic coupling, Common mode noise, Crosstalk.

What process does Samtec employ for making connector models?

Samtec employs an industry proven ladder lumped element modeling process. The elements are derived using 2D field solver software. Samtec is also investigating other modeling techniques (e.g., full 3-D modeling, measurement-based modeling) which would be better suited for more complex structures (e.g., cable assemblies, flex circuits).

How can I view your connector models?

The models are text files that can be viewed with any text editor.

What are the “boundaries” of your connector models?

Typically, SMT connector boundaries are defined to be from the male connector’s SMT tail to the female connector’s SMT tail (SMT pads are NOT included). For T/H connectors, the boundaries are defined to be from the PCB surface of the male connector to the PCB surface of the female connector. For all connector models, terminations, driving sources, and parasitic capacitance are NOT included. For card edge connectors, the boundaries are defined to be from the SMT tail (or PCB surface for T/H) of the connector to the route-out side of the edge card pad (edge card pad is included).

Does Samtec validate their connector models?

Samtec’s connector models are classified as one of the following:

• Validated: Model created using Samtec’s defined modeling techniques. Simulation data from the model correlates with test data from the connector.
• Developmental: Model created using Samtec’s defined modeling techniques, but has not yet been correlated against test data. These models may be “soft validated”, where simulation data from the model is correlated with data obtained from a full wave 3D simulation.
• Estimated: Model was created using engineering approximations (e.g., design similarities with another connector that has been modeled).

What CAE vendor formats does Samtec provide connector models for?

Samtec supports the following simulation tools with connector models: Synopsis HSPICE, Cadence PSPICE, Mentor Graphics ICX (MMF format), Cadence SPECCTRAQuest SigXplorer (DML format), HyperLynx LineSim (SLM format), and HyperLynx 7.5 ELDO.

Will Samtec’s HSPICE and PSPICE models work with other SPICE-based simulation engines?

Yes, the structure of the SPICE connector model is such that it should run in simulators based on Berkeley SPICE 3F5.

Does Samtec offer IBIS models?

The standard IBIS specification does not directly support connector models. It is the IBIS ICM specification that defines the connector model formats (reference https://ibis.org/icm_ver1.1/icm_ver1_1.pdf). Samtec does not explicitly support the IBIS ICM format. ICM identifies “S-parameter” as a model type. Samtec provides S-parameters of our mated interconnects, packaged in Touchstone format, which is the format that the majority of signal integrity simulation tools can work with.

What if I do not see a connector model available for the connector I am interested in?

Contact our Signal Integrity Support and communicate your need for a model. We will work with you to help assess what is required and then add the request to our model production schedule.

RoHS and Lead-Free

What are ELV, WEEE, RoHS and Penta/Octa?

ELV (EU Directive /53/EC) The End of Life Vehicles Directive aims to reduce the amount of environmentally unfriendly waste from ELVs.

WEEE (EU Directive /96/EC) The Directive on Waste Electrical and Electronic Equipment.

RoHS (EU Directive /95/EC) The Reduction of Certain Hazardous Substances. Lead, Cadmium, Mercury, Hexavalent Chromium, Polybrominated Biphenyls (PBBs) and Polybrominated Diphenyl Ethers (PBDEs) are banned from most electronic products offered for sale in Europe effective July 1, .

Are you interested in learning more about Wire to Board Connector Manufacturers? Contact us today to secure an expert consultation!

Penta/Octa (EU Directive /11/EC) This directive bans the use of PentaBDEs and OctaBDEs. This directive is currently in effect in EU. The two banned substances are fire retardant additives (Pentabromo diphenyl ether and Octabromo diphenyl ether).

What is driving the move to RoHS compliant/lead free (Pb-free) products?

In an effort to reduce the amount of electronic waste spreading across European landfills, the European Union (EU) has banned most electronic products containing intentionally added lead and other hazardous chemicals.

Why ban lead?

Lead is only 1 of 6 banned substances. But because it has many different uses lead is the most prominent substance detailed in the RoHS directive for Electronic and electrical equipment manufacturers to be concerned about. Lead is a core component of the solder that goes into the manufacture of printed circuit boards (PCBs). PCBs are increasingly used in everyday household items, from toasters to DVD players and are increasingly finding their way into landfills across the world. The acidity of rainwater washes the solder lead from crushed PCBs. The lead can eventually end up in drinking water supplies. Lead can affect almost any organ and system in the body. The most sensitive is the central nervous system, particularly in children. Lead can also damage the kidneys and reproductive system, and cause anemia.

Is this legislation global?

While the implementation deadlines form part of the EU legislation, the need to comply will evolve globally. It is unlikely that electronics manufacturers will make “lead free” components for Europe and lead-based components for the rest of the world.

Does this affect Samtec products?

Yes, but it depends on the part number. WEEE impacts packaging materials as well as products.

Do Samtec products contain quantities of Cadmium, Hexavalent Chromium, Mercury, Lead, Polybrominated Biphenyls (PBBs), Polybrominated Diphenyl Ethers (PBDEs), PentaBDEs or OctaBDEs?

Generally speaking Samtec products do not contain Hexavalent Chromium, Mercury, PBBs, PBDEs, PentaBDEs or OctaBDEs. It is possible unintentionally added, inherent, trace or near trace amounts of Cadmium and Lead may be contained in Samtec products. At this time, Samtec cannot claim that all packaging materials are compliant with the RoHS and/or WEEE Directives.

Do you have a policy statement on the lead-free environmental issue? Is this available on-line?

Yes. You may also download the latest Samtec Environmental Policy.

Will Samtec provide a formal RoHS CoC (Certificate of Compliance) for their products?

Yes, upon request, Samtec will provide a formal CoC. Please provide Company name and address as well as Company contact and contact information of the person requesting the CoC along with valid Samtec part numbers to our General Technical Support Group.

What lead-free plating is available on Samtec products?

The majority of our plating is lead free and/or RoHS compliant. CLX products or any contact that is pre-plated may not be compliant. Depending on the part number, plating call out and the processing temperatures you may need to choose a Matte Tin finish. Bright Acid Tin will discolor at the elevated processing temperatures of lead-free, reflow soldering and will need to be changed to Matte Tin (TM, LM, FM or SM plating designations). The plating options should be listed in the catalog and/or on the print.

Is Samtec’s gold plating always lead-free and RoHS compliant?

Yes, Samtec’s gold plating is always lead-free and RoHS compliant (pre-plated or in house plated).

Are there any other technical or product specifications that are likely to be affected?

This depends on the part number. If a part contains intentionally added lead, or if the processing temperatures are increased and the current insulator can’t withstand those temperatures, the composition of the part must be altered to accommodate the elevated temperatures and eliminate the intentionally added lead (unless there is an approved Directive exemption as in the case with the brass alignment pins). This would require a part number change.

Are Samtec lead-free parts compatible with the elevated temperatures of lead-free processing?

It depends on the part number. In the left hand margin of the catalog pages under specifications, you will find the processing information. Reflow processing will need a high temp body and matte tin finish. Samtec recommends through hole parts that have a high temp insulator be changed to matte tin as well.

What is the MSL (Moisture Sensitivity Level) classification of your lead-free products? Do your parts comply with J-STD-020C?

J-STD-020C refers to the moisture sensitivity of SMT electrical components. There is no relation or connection to the RoHS Directive. Generally speaking, the MSL is not a concern for Samtec parts. We classify all of our SMT parts as MSL Level 1. J-STD-020C is not applicable for through hole parts.

Will your lead-free parts / packaging be marked lead-free, do you comply with JEDS97?

As of October , Samtec is providing a Directive compliancy label on the lowest level shipping container for the majority of products.

Are you intending to change your part-numbering system to reflect a change to lead-free?

It depends on the part number. If the part contains intentionally added lead or if higher processing temperatures will be used, you will need to ensure the plating finish and the insulator can withstand the elevated temperatures. In those cases yes, a part number change will be required.

Do you have a definitive date when lead-free parts will be introduced?

The majority of Samtec’s products are, or always have been, free of intentionally added lead unless specified otherwise by the customer. However, there are several products that are not currently compliant or have exceptions:

• IDSD/IDMD/HCXX cable assemblies - not compliant - expected to be compliant by late November . The connector ends (plastic, pins and plating) are compliant.
• HDR products with leaded solder not compliant - can be ordered special as lead-free and RoHS compliant.
• Any solder ball product is not compliant if the solder balls are included in the part call-out (no current alternate lead-free, RoHS compliant solder ball).
• I-O products are not compliant (a few exceptions)... must check each part number to see if we have material information or declaration.
• Standard “CLX” products that use pre-plated pins are not compliant (must check part number to confirm status).
• Any product containing wire, cable, hardware such as screws, nuts, bolts, metal shields is suspect and should be verified.

Will there be an increase in lead times for lead-free products?

No.

Will there be an increase in the price of lead-free products?

No.

Are there any plans to obsolete any parts due to lead-free?

No.

Are material declarations available for your lead-free products? How do I get to them?

Yes. Currently, material declarations for the majority of Samtec products are available on our website. This accounts for 80% of the top selling products. Lead Free Product Materials Declaration.

Why are you recommending a change to Matte Tin plating?

A plating containing bright acid tin can discolor when exposed to the higher processing temperatures of lead-free, reflow soldering. Therefore it is recommended that the BAT be changed to change to Matte Tin. We are recommending that through hole parts with high temp insulators also be changed to a matte tin finish.

Are your products compatible with Pb assembly procedures (backwards compatible)?

Yes.

Are your products compatible with Lead Free processing?

This depends on the part number. The composition of the part determines the processing compatibility. You must determine if the part is free of intentionally added lead as well as ensuring that the insulator and plating finish can withstand the elevated processing temperatures.

Are you claiming exemptions for any parts?

Yes. Parts with brass components (such as brass Alignment pins) may contain intentionally added lead. The brass components (a copper alloy) contains a quantity of intentionally added lead within the 4.0 wt. % exemption of the RoHS Directive for copper alloys in electronic components.

Who is your specific contact/Project Manager regarding any technical or other issues?

Please direct all inquiries to the General Technical Support group.

For more information, please visit 2.54mm Pitch Idc Socket Connector.