A.4.2.6. SOP packaging and solder bounding – Method used in baseline tyre transponder design
Two different style RFID transponders can be used. Each tyre uses a Mini Small Outline Package (MSOP – Ref. JEDEC MO-187E/AA) packaged chip solder attached to antennas. An MSOP is a traditional electronic package employed to protect the chip from its environment, including the ability to cure the device into rubber. Other attachment techniques such as flip chip or bonding have not been proven to be sufficiently robust in the tyre application. One style of a MSOP tag may be manufactured on a flexible substrate. The other style of MSOP transponder has spring wire antenna solder bonded directly to the MSOP on miniature thin board. Compliance with environmental directives(e.g. RoHS) can require process changes due to materials’ characteristics. Lead-free solder reflow will likely require higher temperatures resulting in higher peak component temperatures. Care should be taken to ensure against package damage due to higher internal pressure resulting from absorbed moisture.