Evaluating the Effects of Bending on Electrical Components Mounted on Flexible Printed Circuit Boards

Flexible printed circuit boards (FPCBs) made of polyimide are commercially available but are not often used for electronic systems such as power converter systems in wearable devices. The purpose of this study is to explore the effect of bending on the integrity of surface-mount components soldered onto an FPCB during and after flexion. The impedance of the component was measured to observe how bending affect the electrical characteristics of the component soldered to an FPCB. The results show that simple bending of around 70°-80° has no significant effect on the impedance of the components and their solder joints across all resistor sizes. These findings can help engineers develop design practices that improve the reliability of power converters implemented on FPCBs. However, more studies with extreme bending conditions need to be conducted to determine significant changes in impedance behavior.