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| Praetorian EMI Filter Architecture for Wireless Handsets California Micro Devices has introduced a new generation of its proprietary Praetorian architecture and products as part of its ASIP (Application Specific Integrated Passive) EMI (electromagnetic interference) filter portfolio. The Praetorian CM1460 EMI filter offers outstanding filter performance combined with a high level of ESD (electrostatic discharge) protection in an industry leading TDFN (Thin DFN) package. This high performance single chip solution based on a 3 pole L-C architecture leverages CMD's proprietary Praetorian process technology that allows the integration of spiral inductors on silicon. The Praetorian CM1460 provides both superior EMI filtering and ESD protection for interfaces connecting the host processor to the camera and display modules in wireless handsets. In popular clamshell and slider phone configurations, such interfaces are typically routed on a flexible printed circuit board, highly vulnerable to EMI radiation and potential ESD strikes. In addition, as data rates increase and signal integrity requirements become stricter, the use of traditional EMI filters based on R-C (Resistor-Capacitor) architectures results in significant signal degradation leading to potential application issues such as visible data corruption on the display. Each channel of the CM1460 consists of a 3 pole L-C filter with a minimal inductor value of 17nH and nominal capacitor values of 15pF. Its insertion loss is much lower than R-C filters, typically less than 1dB. With a typical corner frequency of 300MHz, rolloff of 20dB/octave and attenuation greater than 30dB between 800MHz and 3GHz, the CM1460 offers industry leading filter performance. In addition, the CM1460 also features robust ESD protection up to +/- 15kV contact discharge per IEC61000-4-2 Level 4 specification and +/- 30 kV using the Human Body Model (HBM). In order to accommodate various interface configurations, the CM1460 is available in 4, 6 and 8 channel versions. The device is housed in an industry leading Thin DFN (TDFN) package featuring a typical height of 0.75mm and body sizes of 2.00mm x 2.00mm, 3.00mm x 1.35mm and 4.00mm x 1.60mm for the 4, 6 and 8 channel versions respectively. Using the Praetorian CM1460, wireless handset designers can benefit from the highest levels of EMI filtering and ESD protection while still meeting host processor requirements for input setup time as low as 2ns on the imager interface. The CM1460 provides EMI filtering and ESD protection in a single chip compared to ceramic filters that require the use of external discrete ESD protection devices. The reduced part count optimizes the footprint and lowers the overall bill of materials. write your comments about the article :: © 2006 Computing News :: home page |