FSA1211 Camera Isolation Switch for Portable Devices

(Product News, 18 Jun 2009)

Fairchild Semiconductor brings designers of 3G smartphones, netbooks, set-top boxes and notebooks the “industry’s first” image module switch that isolates parasitic components to maintain signal integrity. The FSA1211 is a 12-port, single pole, single throw (SPST) analog switch that isolates the high speed bus from parasitic components in dual camera applications. Smartphones feature dual cameras and as these cameras move to higher and higher resolutions, parasitic components play a critical role in deteriorating signals and generating unwanted EMI.

With a bandwidth in excess of 720MHz and high ESD (5.5 kV), the FSA1211 offers an optimal way to isolate capacitance and maintain signal integrity for high speed data paths. In addition, when isolating the unused parallel interface, the FSA1211 reduces the radiated EMI of the path, improving RF desense. The traditional parallel solution can deteriorate the signal due to the unwanted “stub,” resulting in image degradation of the camera module. Another approach is to use three analog switches, which complicates design and adds to the overall bill of material (BOM) costs. In contrast, the FSA1211 offers robust isolation and ease of design at a lower cost.