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impedance matching

true wanderer

Hi,

In my circuit, a chip antenna(ANT016008LCS2442MA2)is used in the circuit for Bluetooth low energy. Balun(HHM1711D1)is used for impedance matching and to achieve compatibility between feedline and antenna.It's recommended to connect BLE pins & balun with 100 ohm differential lines and balun & chip antenna with 50ohm differential pair. How can i match a trace for a particular impedance. I think the impedance depends most importantly on the trace width and also the thickness of the dielectric right? So I think i need to consult with the pcb fab house. Am i right? What are the parameters that i should ask them to get my PCB done as per the recommendation? 

Any help would be appreciated 

  • Layer stackup, finished copper thickness, substrate thickness and Er, coating (solder mask) thickness and Er

  • The layer stack that I used is as follows :

    Layer 1 : TOP-for signals(conductor)
    Layer 2 : GND_T(plane)
    Layer 3 : Signal(conductor)
    Layer 4 : Power(plane)
    Layer 5 : GND_B(plane)
    Layer 6 : BOTTOM-for signal lines(conductor)
    The parameters given by Fab house is as follows : PCB Thickness: 1.6 mm
    Surface Finish: Immersion GOLD/ENIG
    PCB Dimensions 60.00 X 60.00 MM Start Cu Thickness: 17.50 μm
    Panel Dimensions - I/L Cu thickness 35.00 μm
    PCBs/Panel - Finish Cu Thickness 35.00 μm
    Top Solder Mask-Green
    Bottom Solder Mask-Green
    Top Legend White Bottom Legend White
    TG Std. Tg ( 130-140 °)
    Layer Build-Up Standard
    Via Fill-No Peel Off No-Peel Off
    Carbon contacts- No Carbon Contacts
    UL Logo- No
    Edge Connector: 0.00
    Edge Connector: Au
    Thickness: 0 μm
    Blind & Buried Via: Blind via
    Impedance Control : No . Is there any additional parameters required to complete routing? I think i need to use layout cross section menu in allegro to complete this task. Am i right? Which value should be put in the column for thickness of dielectric,conductor &plane(GND_B,GND_T &POWER)? I think i need to set the required impedance(say 50 ohm) by ticking the check box "show single impedance/Diff impedance". Then allegro will calculate the required line width. I hope this is the right method. Please correct me if i'm wrong.

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