CG2409M2-EVAL CEL

Evaluation Board Document CG2409M2-EVAL Evaluation Board o Description o Insertion Loss of Through Board o Assembly Drawing Description: The CG2409M2-EVAL is evaluation board for CEL s CG2409M2 GaAs MMIC switch. A DC blocking capacitor is required at all RF ports. On this board, an 8pF capacitor is used in accordance with the condition specified in the data sheet. The chosen capacitance value is optimized over the entire specified frequency range. For a narrow band application or an application where the operation frequency is outside the specified frequency range, the user may select a different capacitance value. Generally, the performance of the switch circuit is not sensitive, to a certain extent, to the DC blocking capacitance. A 1000pF capacitor is used for DC bypass on all control lines. The user can make adjustment on its value according to the specific application requirement. DC and RF Connections All ports for DC and RF connections are labeled on the board. For the complete pin-out description, refer to the data sheet. Board Material: The board material is 20 mil thick Duroid 6002. Its dielectric constant is 2.94. Switch Logic Table: The following is the logic table for switch states. VC1 VC2 RFC RF1 RFC RF2 H L ON OFF L H OFF ON Insertion Loss of Through Board: The measured insertion loss of the evaluation board is a combination effect of the switch, RF connectors, board traces and series DC blocking capacitors. Since the insertion loss of the switch is generally small, the board loss should be subtracted from the measurement for more accurate evaluation of the switch performance. The table below lists the through-board loss at various frequencies. INPUT FREQUENCY (GHz) BOARD LOSS (dB) 0.5 0.05 1.0 0.07 1.5 0.11 2.0 0.12 2.5 0.13 3.8 0.18