
350Ω planar rosette strain gauge pattern for PCB stress-in-manufacture testing
Next-generation manufacturing processes are calling for thinner board (PCB) designs and newer laminate material types, whil industry trends continue toward the adoption of RoHS compliant assembly technologies, including lead-free soldering techniques. Both trends, the company says, have increased PCB failure risks, due to added potential for over-flexure in the manufacturing process. With many PCB assemblers operating under customer-specified strain levels, any over-flexure can lead to interconnection damage, premature field failures and product returns. As a result, manufacturers are increasing supply chain requirements for PCB mechanical stability testing.
Offered in two strain gauge designations (C5K-XX-S5198-350/33F and C5K-XX-S5198-350/39F), the Micro-Measurements S5198 pattern provides precise strain detection with minimized non-uniform PCA strain gradient effects, along with reliable operation to +200°C. A resistance specification of 350Ω, as compared to the 120Ω typical industry standard, reduces the unwanted self-heating and heat dissipation effects commonly found among substrates with poor heat conductivity, such as PCBs. A reduced overall footprint, with grid length of 0.36 mm, facilitates ease of target board placement and integration. The S5198 pattern is further supported by pre-attached high-performance Teflon insulated flexible thin cables, consisting of three twisted wires per grid. The wires are colour coded, stripped and tinned for ease of PCB wire routing and connection to data acquisition systems. In addition to PCB testing, the pattern is suitable for ball grid array (BGA) component testing, spherical bend testing, mechanical shock testing, PCB flexures, and in-circuit testing (ICT). The S5198 is RoHS compliant and is utilized in accordance with IPC–JEDEC 9702, IPC–JEDEC 9704, and JEDEC JESD22-B111 standards.
Micro-Measurements; www.micro-measurements.com / www.micro-measurements.com/list/product-11138/
