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How to get the loading capacitance of a certain instance by encounter?

qijianfei

 Dear All,

 If I know the instant name and its output pin's name. How can I use encounter to get the loading capacitance of that pin? Which command should I use? 

 

Thanks

qijianfei

  • Here's an example: 

    report_property [get_nets [get_property [get_pins DTMF_INST/TDSP_CORE_INST/TDSP_CORE_GLUE_INST/i_962/Y] net_name]]

    total_capacitance_max_fall          | 0.006
    total_capacitance_max_rise          | 0.006
    total_capacitance_min_fall          | 0.006
    total_capacitance_min_rise          | 0.006
    wire_capacitance_max                | 0.002
    wire_capacitance_max_fall           | 0.002
    wire_capacitance_max_rise           | 0.002
    wire_capacitance_min                | 0.002
    wire_capacitance_min_fall           | 0.002
    wire_capacitance_min_rise           | 0.002 

    You can query individual values with get_property which should also accept specification of a -view:

    get_property -view default_analysis_view_hold [get_nets [get_property [get_pins DTMF_INST/TDSP_CORE_INST/TDSP_CORE_GLUE_INST/i_962/Y] net_name]] wire_capacitance_max 

    Hope this helps,
    Bob 

  • Does this net capacitance include the input capacitances (gate capacitances) of the input pins connected with this output pin? 

    Thank you so much Bob.

  • I believe total_capacitance does include input pin cap(s), wire capacitance does not.

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