Hi, Does anybody know where can I find detailed information on class(1-5) as used in 'emc rule checker' in Allegro? Also, do they have any connection with industry standards like ClassA,ClassB... I'll appreciate any help. Thanks, Saad.
Hi Saad, EMControl requires that you assign a critical frequency class property to significant, or critical, components and nets before you perform EMC rule checking. Critical components include ICs that are relevant to rules that examine critical ICs, line drivers, line receivers, fast-switching transistors, or bi-directional transceivers. EMControl supplies up to five critical frequency classifications to describe the EMC characteristics of the ICs and nets in a design. There are up to five classes for components in a design. You can specify the corresponding variable value for each component class. You have CLASS1 through CLASS5 for these settings. For components, the fastest drivers result in a Frequency Class1 designation and the slowest drivers are designated a Frequency Class5. The EMC rules you apply to nets and components use this class designation. You can attach critical frequency classes (EMC_CRITICAL_IC, EMC_CRITICAL_NET, EMC_CRITICAL_REGION) to design objects automatically using the Manual Property dialog box from the EMC rule checker. When you identify the CLASS of the component you can also identify the type of component by adding the EMC_CVOMP_TYPE property. For each class of component you can also identify the Voltage swing and the Rise/Fall time In the EMC setup you can also define the EMI Regulation that you need to check against - FCC Class A, FCC Class B, CISPR Class A, CISPR Class B, USERDEF_CLASS, VCCI Class 1, VCCI Class 2