Stackup Designer and Impedance Calculator Demo

Pranav Manjanath Tengse

Project Engineer
Sierra Circuits

A little bit about our tools

Our Stackup Designer provides precise options for cost-optimized build-up structures with a library of stack-ups, including single and sequential lamination build-ups, with a variety of material databases suitable for a wide range of applications. The tool automatically chooses the type of board construction based on material selected and is linked to our 2D field solver-based impedance calculator which allows you to design any controlled impedance traces. It offers 3 technology levels with respect to different parameters such as trace geometry, drill sizes, spacing, and cost index. The cost index provides a relative idea of the cost compared to another layer order. Tool also recommends the stack-up based on the selected BGA pattern.

Our Impedance Calculator is based on 2D numerical solutions of Maxwell’s equations for PCB transmission lines. It renders accurate results suitable for use in circuit board manufacturing and engineering analysis. Along with characteristic impedance, it provides the capacitances, inductance, propagation delay and effective dielectric constant of the structure. It offers odd and even mode parameters for differential pair structure, and a dielectric constant table for commonly used materials provides the dielectric constant and dissipation factor at different material thicknesses and resin content at 10GHz.

Best features of the Stackup Designer

1. It has a library of stack-up templates. The templates include single and sequential lamination build-ups (HDI-1, HDI-2, HDI-3, and HDI-4). The digits here represent the number of sequential laminations. For example, HDI-2 has core plus 2 laminations.

2. It includes a variety of material databases suitable for a wide range of applications (low to very high-speed).

3. It is based on the material selection, it automatically chooses the type of board construction (foil or core type).

4. To meet the requirements of high-speed designs, the tool is linked to our 2D field solver-based impedance calculator which allows you to design any controlled impedance traces.

5. It offers 3 technology levels (level I/II/III) with respect to different parameters such as trace geometry, drill sizes, spacing, and cost index. Features such as drill size and trace geometry of technology level II are finer than technology level I and the features of technology level III are finer than level II.

6. The cost index provides a relative idea of the cost compared to another layer order. For instance, if the cost indices for build-ups A and B are 2.6 and 1.3 respectively, then A is roughly twice as expensive as B.

Best features of the Impedance Calculator

1. Our impedance calculator features two main types of impedance models, single ended and differential, within each trace structure.

– There are 3 types of single ended models- single ended, coplanar single ended, and coplanar single ended without ground.

– There are also 3 types of differential models- differential, coplanar differential, and coplanar differential without ground.

2. We have 82 impedance calculators that are designed and categorized based on the different trace geometries.

3. Whether the traces are embedded in between layers or on the surface of the circuit board, designers can easily choose the right type of calculator to suit their design needs.

4. Calculate accurate impedances for PCB models having different dielectrics: PCB models that use different dielectric materials to achieve the desired impedance accuracy have been earmarked as composite models ‘A’, ‘B’, and ‘C’. The impedance calculator features composite geometry where the traces are embedded between different dielectric materials having different height and dielectric constants to achieve accurate impedance values.

5. The units can be changed as per your requirement. You can take the print out of your final readings by clicking the ‘print’ button.