Compliant Pins

Many industries that use electronic connectors have adopted the application of compliant pin technology for the connector interface with the printed circuit board (PCB).   The compliant pin, also known commonly as a “press-fit” pin, contains a compliant section on the end of the terminal that interfaces with the inside diameter (ID) of the through-hole of the PCB when “pressed” firmly into the PCB through-hole.    When the compliant pin is used, the soldering process and its cost are completely eliminated.    Both the PCB through-hole and the compliant section of the terminal are typically plated either with tin or silver.   The compliant section of the pin is designed with a spring action that maintains a minimal acceptable normal force against the ID of the PCB through-hole once inserted into the PCB, and thus maintains a good electrical contact of the pin with the PCB.   The end of the pin that fits into the PCB through-hole “complies” with the ID of the through-hole; thus the name “compliant pin”.   In many designs, the compliant pin may also be extracted from the PCB through-hole for repairs or PCB replacement if needed.   And because the compliant section of the terminal has a “spring” characteristic, it maintains an acceptable normal force against the ID of the PCB through-hole in a variety of temperature ranges, vibration ranges, and impact-test ranges.   Thus, even when temperature, vibration level, and impact vary significantly, the compliant pin maintains a good electrical contact with the PCB through-hole.   While a solder joint may crack or break with variations of temperature (which causes expansion and contraction cracks) and vibration (which may cause vibration cracking), the compliant pin simply expands and contracts with these variations because of its spring-loading against the ID of the PCB through-hole.

Neutronic Stamping & Plating has been manufacturing compliant pins since 1978 for the telecom, automotive, industrial, and consumer electronics industries.    Neutronic is a pioneer in the development of the best performing and highest reliability compliant pins.   For the more than 35 years of manufacturing compliant pins, which has resulted in hundreds of millions of pins being sold, Neutronic has never had a customer complaint of a compliant pin failure.   Neutronic manufactures compliant pins from various copper alloys and also from stainless steel.   Neutronic has a patented compliant pin design, but we also stamp compliant pin designs that are specifically requested by our customers.

Before compliant pins are approved by most customers for use, extensive testing is required to insure that the pins maintain acceptable electronic conductivity with the PCB in a variety of conditions including vibration, impact, temperature range, thermal shock, high inertia, high humidity, corrosive atmosphere, and some combinations of these environmental conditions.   Neutronic compliant pins have passed the testing of several major Tier One automotive suppliers and several telecom & consumer electronics customers.    Neutronic has done extensive testing in-house on compliant pins and is still performing testing for new designs and to meet new customer test requirements.    Neutronic also has the capability to make cross-section analysis of compliant pins when inserted into PBC through-holes to assess the quality of the interface between the PCB and the pin.   And Neutronic has capability to supply prototype compliant pins for customer evaluation.   In summary, Neutronic is the technical leader in compliant pin technology worldwide, and a world leader in compliant pin manufacture.