The Smith Chart graphically maps S11=reflection coefficient= (ZL-Z0)/ (ZL+Z0) to Load Impedance (ZL), normalized to Z0 (source impedance = center of chart). Right-click on ‘Net classes’ >> click on ‘Add classes. This means that the actual trace width for a 50 ohm line could vary from design to design. In the absence of a specification for the bus standard or the receiver timing, you can apply a rule of thumb such as keeping the skew to less than 5% of the clock period. You want to select “Microstrip Zdiff”. CAN_L is pin 2 and CAN_H is pin 7 on the standard 9-pin D-SUB connector. Another example of using large distances to separate out unwanted components might be to calculate the impedance of a. Every trace has series inductance. It supports both balanced and unbalanced lines. 5. In general, it is double the odd-mode impedance, which is the value we care about for differential signaling, as it is used in high-speed PCB design. So, the trace width and distance to adjacent reference plane is determined by the desired. When the termination resistor matches the track impedance, there will be no reflections. Board Setup. (unloaded trace impedance, Ohms) = Tpd (unloaded propagation delay, ps/unit len) =. 0. The USB 2. Use the following equation to calculate the impedance of a stripline trace layout. Controlled differential impedance starts with characteristic impedance. This calculator is designed to find the characteristic impedance of an asymmetric stripline - a flat conductor between two ground planes. Mutual inductance and capacitance exist between the two traces in a differential pair. 1. Please bear in mind the copper trace, minimum etch, manufacturing capability etc of the pcb supplier. Trace Impedance. While discontinuities might be unavoidable, they should be lumped together to keep their area small. In terms of the characteristic impedance in line 1, mutual impedance, and current in line 1, the odd mode impedance is: Odd mode impedance for differentially-driven transmission line. 1. This is the same reason we have to consider spacing between traces in differential pairs: the two conductors interact with each other to determine the odd-mode (and differential) impedance . The required inputs are the Dk value for the dielectric constant of the PCB substrate, and the. This calculator finds both odd and even transmission line impedance, including four different types of impedance used in characterizing differential trace impedances, for microwave antennas, couplers and filters applications. We recommend the software from Polar Instruments if you want to get exact impedance calculation. If your schematics call for 50-ohm single-ended routing, you would want to use 100-ohm differential routing. Differential Trace Routing. Supports Anritsu ShockLine™ MS46524B and VectorStar™ MS4647B. The main takeaway for me: To get to around 80 ohms, I should not pull ground on the signal. e. High-speed designs carry a requirement for controlled impedance, crosstalk control, and the need for interplane capacitance. Measure all parameters S11, S12, S21, and S22. KiCad 5. Signal layer. This note describes some. The main difference between a 2 and a 4 layer board is the distance to the ground plane: On a 4 layer board the typical distance between the outer and inner layer is around 0. Zachariah Peterson | Created: November 22, 2021 | Updated: June 25, 2023 Table of Contents Differential Impedance Defined Formulas for Differential Impedance Should You Use Characteristic or. The characteristic impedance of your microstrips is determined by the trace width for a given layer stackup. Figure 25. The width of each track should be as per the requirements. TheseIt always defaults to 10mil. Controlled Impedance; PrePreg Chart. Cross-section geometry of a stripline trace. • Differential impedance is the impedance the difference signal sees • With no coupling, current into one line depends on capacitance per length of. Coplanar Waveguide With Ground Characteristic Impedance Calculator. Modeling approximation can be used to design the microstrip trace. Compatible with Flex PCBs and Turnkey PRO service. Differential Impedance of Microstrip. 2. The length matching of these differential pairs is important because these two lines are time-dependent or. Z 0 = Single Ended Impedance. 2. Single-ended signals are fairly straightforward. Differential Impedance Ω. Controlled impedance (CI) is the characteristic impedance of a transmission line in a PCB conductor and its related reference planes. The reference plane is not far enough to accommodate 100-ohm differential impedance. Track width (w) = 137 micron. Broadband Impedance Matching with Transformer; Ferrite Toroidal Coil (Amidon) Helical Coil Calculator; Impedance Calculator : XL, XC; Iron Powder Toroidal Coil (Amidon)Differential impedance is another factor you should probably consider when dealing with impedance. Typical impedance tolerances are 10% and 7%, and can go as low as 5% or 2% in the extreme cases. While this calculator will provide a baseline, any final design considerations should be made towards loss, dispersion, copper roughness, phase shift, etc. Using 0. 2) S/T > 5. Question #1: How to determine the required spacing between length-matched signals or differential pairs and the adjacent layers? If you are length matching that implies that the interface is probably fast enough to require controlled impedance. If you are using differential pairs, think about trace coupling. Differential Stripline Impedance Calculator. e. 1 or 4. when i use Saturn PCB design to match the differential impedance to 100ohms i get 0. This impedance is dominated by the physical separation between your power rails, traces, and internal planes in your board. they normally use 7. The Differential microstrip impedance calculator is used to compute the differential (Zd) and single-ended impedance (Zo) of an edge-coupled microstrip line just by entering the width, separation and thickness of the. Note that Zdiff (differential impedance) is equal to 2 * Zodd, so a Zodd of 45 Ω gives us a Zdiff of 90 Ω. The calculator by Spok consulting, for example, gave the following result: Problem. Expect a large variation of manufactured PCB impedance with 0. Wavelength/10 is the max trace length before you need to worry about impedance control So if you keep your traces under 15mm in length, then it doesn't matter. Differential impedance, Z diff, is the impedance between the two conductors. The characteristic impedance is given by: Eq. FYI, I followed 2nd option and values were quite similar. Going to 100 ohms diff you would be looking at 15 mil parallel traces. Calculate the differential impedance of a microstrip transmission line with this handy calculator. This would also achieve a single ended impedance of 50ohm~. Use an impedance calculator to determine the trace width (W) and spacing (S) required for the specific board stack-up being used. 3. Voltage Divider Calculator 1 (Fixed) Voltage Divider Calculator 2 (Adjusteable) Capacitors. The vias on these differential pairs have their own impedance, which can create signal integrity problems on long interconnects. In the special situation for which there is no coupling to ground, Differential impedance equals the Characteristic. Example Problem: Use the following variables as an example problem to. 68 mils. Use the following guidelines. To find what a given trace width will have a single ended or differential impedance, we can use a built in calculator from Allegro. The tool also calculates signal losses of any given trace. Single Ended Impedance Ω. A differential stripline pair refers to two traces located between two reference plane layers, which are routed as a differential pair. $endgroup$ –When considering differential traces, add the space between traces (s) to this list. We care about maintaining the same differential impedance for. 1 to 3. The tool implements numerical solutions of Maxwell’s equations to render accurate and consistent results. Zo (diff) is calculated to be 244 ohms, so dividing by two yields a value of 122 ohms for the semi-coplanar structure. • Trace mis-match compensation should be done at the point of mis-match. Take note that this assumes that the distance between the conductor and the planes is not the same for both reference planes; hence the asymmetric term. 125; Tolerances; Certifications; RoHS - Lead Free; Electrical Test;. One thing is for sure: When you are routing a high-speed PCB design you are going to be working with impedance-controlled routing and. For differential pairs of microstrips, the formulas involved are much more complicated because coupling between the traces in the differential pair must be included in the impedance calculation. 03) it gives me almost 160 Ohm - and even if use 53mil conductor height or. pairs for aciving 85 Ohm diff. Sierra Circuits can: Help you with your controlled impedance stack-up. Reference: R. 96D/H). There are four different types of impedance used in characterizing differential trace impedances. THESE FORMULAS ARE APPROXIMATIONS! They should not be used when a high degree of accuracy is required. Physical geometries of differential traces To calculate the trace geometries in Figure 5 for a 100 Ω differential impedance TMDS signal pair, the closed-form equations 1 – 6 can. Using an online calculator [4], a microstrip trace of 1oz, 120mil-wide copper on 0. 15 mm spacing. 3mm of the microcontroller), therefore i rounded the width to 0. For differential pairs of microstrips, the formulas involved are much more complicated because coupling between the traces in the differential pair must be included in the impedance calculation. don't change the any dielectrical contant. Just a clean step. Thus a "differential pair" any long distance apart will have an impedance of 98 ohms, without any coupling between the lines, i. ’. Place your components, vias, coupling capacitors. Refer to the Intelâ 5 Series Family PDG for spacingWe get a lot of questions about trace impedance and how to calculate the right trace size to hit a specific impedance in a manufacturable PCB. To maximize signal integrity, proper routing techniques for differential signals are important for high-speed designs. 77 mm gave me a differential impedance very close to 90 Ω. Enter the values of trace width (w), trace thickness (t), trace dielectric thickness (h), overall dielectric thickness (h1), and the dielectric constant (er). The surface finish is neglected. I would like to know how to calculate trace width and gap to route differential pair in this situation. How to calculate track widths and layout controlled impedance traces (e. Conversely, tightly coupled differential pairs have an air gap that is less than the trace width. The spacing between two traces in a differential pair should not be more than twice the width of the traces. Figure 1. For an embedded (internal) microstrip, the formulas provided in paragraph 4. Try TNT or TxLine. D = Separation between the differential traces. To prevent reflections the PCB trace pair’s impedance should be matched to the interconnect/media. Broadside-coupled Asymmetric Stripline. The standard 4-layer stackup uses two inner layers for power and ground, and the two outer layers are for components and trace. I've used 7 mil trace width with 5 mil spacing, top and bottom layers (35um copper) are 0. If the characteristic impedance of the two single-ended lines is Z0, then Zd and Zc can easily be derived. The JLCPCB Impedance Calculator computes track width values and recommended stack-ups from user-input values of board layer, thickness, copper weight, target impedance, trace spacing (for edge-coupled pairs), and impedance trace to copper gap (coplanar waveguides). Keep the trace stub lengths to a minimum. In principle, you can calculate the inductance of a trace with a 3D field solver utility, but this is not the norm in transmission line design. 25mm between the differential pair with a width of 0. PCB Trace Impedance Calculator. Figure 8. For example, with a thickness of 0. I checked out TNT, but couldn't seem to be able to do the same with that either. This calculator finds both odd and even transmission line impedance. Surface microstrip lines are formed by etching one surface of a double-sided material. When designing the trace configuration for your differential pairs, you are typically targeting 100 ohms differential. I did some calculations and it turned out that I have to make the trace that feeds input signal into the. mils: Distance between planes (B) mils: Relative Dielectric constant (Er) Differential. Dial down these variables, calculate exactly what you’re impedance needs to be. 3mm, as shown below: This increases the impedance slightly to 91. determining the value of the differential impedance particularly for surfacemicrostrip differential tracks. The Impedance Calculator evaluates single-ended and differential impedance for various impedance models. We get a lot of questions about trace impedance and how to calculate the right trace size to hit a specific impedance in a manufacturable PCB. Z0 = (60 / √εr) * ln ( (8h) / (w + s)) Where εr is the dielectric constant of the substrate material, h is the substrate height, w is the trace width, and s is the spacing between traces. Yet I got a ZDiff CPW with ground capable calculator: Differential surface coplanar waveguide with ground calculations: *0. The board contains two inner layers of GND and a ground plane around the RF track: To decide the thickness of the RF track, I used an online calculator:. 4mm. Ensuring impedance-controlled routing also requires knowledge of the substrate’s dielectric constant and your required trace width. Figure 13: There are single end trace impedance and distance between traces in the pair. Take note that this assumes that the distance between the conductor and the planes is not the same for both reference planes; hence the asymmetric term. The capacitor value may be traded off to. some trace calculation examples. 2. If you put 10 in the Line Width, the calculator calculates the single ended as well as differential impedance. This calculator is designed to calculate the characteristic impedance of an edge coupled microstrip. I found that a W of 0. View All Tools. A coplanar waveguide calculator will operate in one of two ways. Differential Stripline Impedance Calculator. 2mm from the ground plane below. I wanted to use Altium to calculate the width of the trace automatically, so that it had a 50 Ohm impedance. Differential Pair Calculator The Differential Pair Calculator is used to perform what-if analysis to determine what values of Primary gap and width are needed to get specific differential and single line impedance. High speed measurement tools. differential amplifier 9. Although JLCPCB can produce boards with 2 oz external copper, the calculator only supports 1 oz because (1) the wider tolerance of 2 oz traces hinders impedance control, and (2) most signal traces only carries small currents. See how in your microstrip example the traces are 192 um wide while in the coplanar design they are 117. Assuming the differential pair I am routing is requiring 90 ohm (this is what the hardware guideline say "Route the USB differential pair on the top layer with a trace width and differential spacing tuned to the PCB stack-up. Speedstack Si – Insertion loss & impedance PCB stackup design including Si9000e. The DC resistance is determined by the trace's conductivity and the cross-sectional area. Unit: Options are mm, mil, μm, and inch. They will trim the trace width based on their experience with their stackup, accordingly. 37) If H1<1. So I need to choose the correct trace width/spacing, am I right? Previously I was used 5mils width and 6mils spacing differential traces. Email: info@multi-circuit-boards. The physical parameters of the trace i. There are 3 types of single-ended models: single-ended non-coplanar, coplanar single-ended, and coplanar single-ended without ground. Use the following guidelines. 159 OS X 10_15_7 EasyEDA. Please refer to the pcb trace calculator for dimensioning to achieve the target differential impedance. 2 Ω impedance. Calculate the Differential Microstrip Impedance of a transmission line based on the the distance between the strips, height of the substrate, trace thickness and dielectric constant of the substrate. Missing by 25 microns on a 100 micron trace throws off the alignment by 25%. I'm designing a custom PCB around the Raspberry Pi RP2040 MCU. Unfortunately Online Calculators are deceiving unless you actually draw the numbers and understand the ratios and tolerance effects. With t = 35 um (typical for copper with plating on a pcb), Z odd drops to 44 ohms, according to LineCalc. Use the results from #3 to calculate the width profile with. Design traces for 100 W differential impedance (± 15%). 5. In some cases, we can also use 75-ohm. 1. Ask the board manufacturer for the values. 3 V, etc. 1 to 2. Signals on an FR4 PCB travel at approx half the speed of light, so you'd want to make your longest trace no more than 44 mm longer than the shortest trace. 1 Effective Permittivity and Characteristic Impedance of CPW. Terminate the trace at one end with a small SMT 50 Ohm resistor (49. 2. Formula for Differential Microstrip Impedance Calculator (Using Zo) Where, Z d = Differential Impedance. Differential Impedance: Single-ended Impedance: Significant field collisions (bad design--will be too much crosstalk): In short, do not put much faith in the single calculators you find online. 25. Every trace has capacitance between the trace and the return path of the signal on. 1. 062. Differential impedance. Inductance – the impedance calculator uses the Impedance value to calculate the inductance per unit length. Calculate the trace width needed to hit your impedance target if impedance control is needed. Can I / should I add extra components to the bus traces, to reach. KB: Prevent multiple license seats being used on one installation instance. 3mm of the microcontroller), therefore i rounded the width to 0. 6), the impedance will be approximately 50 Ohms. Most popular calculators don’t even have a box height parameter. Microstrip Impedance -Differential Stripline Impedance -Differential W = Width of the trace H = Height of dielectric above theThe trace width is important as it determines the single-ended and differential impedance, capacitance, and inductance. But these people miss the point. The differential via design shown in Figure 2 was built and tested. 1. Probe with the oscilloscope where the function generator feeds into the PCB. Both LM and CM converge to zero as spacing goes to infinity. An example of this calculation using the Si8000m Quick Solver is shown below in figure 4. Access Advanced Circuits' printed circuit board trace width tool. PCB Impedance-Calculation: Help with the dimensioning of the impedances of your circuit board. Just to give designers a starting point, take a look at these differential impedance calculators you can use to get an initial estimate of the differential. trace width and thickness, distance from other copper features, dielectric constant, and dielectric thickness or distance to reference plane of the board material all contribute to the impedance of a. 3. Example. s εr W W t s h W W t Microstrip Stripline d d Fig. Trace thickness (T) mils. Use the following guidelines. Trace impedance control is a simple matter of properly sizing traces. Calculates the characteristic impedance and per-unit-length parameters of typical printed circuit board trace geometries. Different board materials, the dielectric layer thicknesses and constant (Dk), and the thickness of the metal traces all need to be part of the calculations. 1. Microstrip Trace Impedance Calculator; Stripline Trace Impedance Calculator; Differential Trace Microstrip Impedance Calculator; Differential Trace Stripline Impedance Calculator; The. KB: Route traces between flex and rigid regions. The tool implements numerical solutions of Maxwell’s equations to render accurate and consistent results. Trace Height (H) Figure 4. Sorted by: 1. Most popular calculators don’t even have a box height parameter. There have been trace routing tools available for a long time that help with differential pair routing, and designers have had access to impedance calculators to determine their trace widths. The surface finish is neglected. You can use all the calculators you want if you don't know the exact board make up they're using; they should be able to help you. Just as important as determining an appropriate trace width for a single-ended trace is determination of an appropriate spacing between two traces in a differential pair. Fabricators give trace impedance tables as guides to designers that need to implement controlled impedance in their PCBs. This is why in most cases the differential impedance of a pair of traces is a little less than twice the single ended impedance of each trace. There are some advantages to using a. 4515. Single ended. 093. The default units for all given values, except the subtrate. Commonly, you calculate. width|space|width. Hello! I'm trying to calculate the trace width for a differential pair (carrying MIPI CSI-2 signals), using JLC's impedance calculator. Insertion Loss. Phone: +44 (0)1425 489 111 / +49 (0) 8104 628 0. This calculator can calculate the impedance and propagation delay of the embedded microstrip. What we have on these differential traces is a taper section, which RF engineers often use to match impedances. Note that the y-axis is on a logarithmic scale for clarity. 77 mm gave me a differential impedance very close to 90 Ω. Wavelength calculator Calculates the wavelength of a signal using Ereff. 30967mm) is slightly larger the size of the smallest pad (0. The equations in the MeasEqn block shown in Figure 14 are used to calculate the power delivered to the 50 Ω load on the balun output. My board house can do 5/5 mil trace/space. Open the PCB layout tool (pcbnew) and go to File > Board Setup. The JLCPCB results are more reliable than (some of) the simple formula-based approaches. We get a lot of questions about trace impedance and how to calculate the right trace size to hit a specific impedance in a manufacturable PCB. Try TNT or TxLine. The characteristic impedance is given by: Eq. IPC 2141 Trace Impedance Calculator. SET2SEIL. To avoid microstrip modes, have h >> (w+2g) and extend component side ground away from the trace by > (w+2g). • When using an impedance calculator, the outer layers of the PCB contain less glass than. 8. Coplanar waveguides are open quasi-TEM waveguide geometries that use copper pour and a ground plane to provide shielding along the length of a PCB trace. 6mm 4 layer PCB, 1oz outer copper, 0. # Impedance trace/space. A 3D view of a complex impedance controlled PCB in. Use several of them and compare. Single Ended Impedance Ω. Note: The 6-Layer board temporarily only provides JLC3313 Stackup. Select the box with the geometry that you would like to calculate. Therefore, for fast enough rise times, the impedance it offers can be significant. PCB Impedance and Capacitance Calculator: Asymmetric Differential Stripline. If the width of the trace is two times the height of the dielectric (for FR4, Dk from 4 to 4. The characteristic impedance Z 0, or the load impedance Z L, can be calculated with the value of ρ. Enter the differential impedance you want, the trace width, the dielectric height, the dielectric constant, and the trace thickness, and click the. From this equation, calculate the real and imaginary components to. ALGEBRAIC EQUATIONS Single Track For the stripline of Figure 2 with a symmetrically centredIf your design has controlled impedance traces, you can use our built-in impedance calculator. To find what a given trace width will have a single ended or differential impedance, we can use a built in calculator from Allegro. The PCB design tools in Allegro include an impedance calculator that will help you size your traces so that they have defined characteristic impedance. 15 mm. • Keep single-ended signals away from differential traces – distances should be at least at least 2x the trace width. com To use this tool, enter the values for trace thickness, substrate height, trace width, trace spacing and subtrate dielectric in the calculator above and press the "calculate" button. While commonly constructed using printed circuit boards, this structure can also be built using other materials as long as there is a conductor separated from. Regarding the impedance of USB signal traces the layout guidelines state: DP, DM Differential trace impedance = [DP(45ohm) + DM(45ohm)] = 90 ohm, and do not jump the DP DM signals that cause impedance miss match. When routing the board, make sure to make that trace width unique. Yes, solder mask can lower the single line impedance by 1 - 2 ohms and the differential impedance by 3 - 4 ohms for thin traces. There are four different types of impedance. Choose a calculator to tune your PCB design. Spacing and width value pairs that will give a differential impedance of 100 Ohms on Dk = 4. This calculator. While this calculator will provide a baseline, any final design considerations should be made towards loss, dispersion. Introduction The edge couple differential microstrip transmission line is a common technique for routing differential traces. This transmission line calculator. While commonly constructed using printed circuit boards, this structure can also be built using other materials as long as there is a conductor separated from. Doubt about 50 ohm impedance calculation. Differential Trace Microstrip Impedance Calculator; Differential Trace Stripline Impedance Calculator; The standard geometries that are supported by these trace impedance calculators. 1mm (3. Agilent's LineCalc tool calculates Z odd = 50. This makes the problem of determining impedance much more complex, and building an initial lossless model requires a larger set of formulas. Use the Series and Shunt Impedance Calculator: to try your own impedances; Change Grid: S11, (ZL normalized to source impedance Z0)Overview. They are very simple to read, and the values in. ZO *. Use an online differential microstrip impedance calculator; Use an online differential stripline impedance calculator; Calculating Differential vs. Differential signaling in flex circuits follows the design method of surface microstrip transmission lines. Trace thickness is 0. 9 Ohms). Chrome 92. Given the defaults (1. EasyEDA directly supports controlled impedance designs for 4 and 6 layer PCBs only. Simulation Done with PCB Trace Differential Trace Impedance of 50 Ω and Trace Length of 50 psec. To obtain a particular value of differential impedance, the two signal tracks are usually assumed to have the same cross-section — the balanced track case, used in most impedance calculation software. The differential impedance target, as well as the single-ended impedance of each trace, is maintained by keeping the spacing between the two traces constant. The ground plane helps. 72e-08. Stripline Impedance. The stripline impedance calculator provided below is useful for gaining an initial estimate of trace impedance for striplines. Figure 25 shows a differential pair using the microstrip layout. 36) Co Equation: IPC-D-317A (Eq. The IPC-2141 trace Impedance calculator will help make initial design easier by allowing the user to input basic parameters and get a. Consider some of these vital PCB routing guidelines: Keep fixed impedance traces for a particular interface or signaling protocol on the same. The Saturn PCB Toolkit is the best freeware resource for PCB related calculations you can find. I've used ADI's Diff Amp Calculator since I started this circuit (quite a long time ago) and it helped a lot. How to calculate differential impedance: Notes. In this worst-vase scenario, the via would. Rule 2 consequence. Before, working with a trace impedance calculator, one should be aware of which equations the calculation uses. Once you know the characteristic impedance, the differential impedance. Your signaling standards will determine your routing needs, including total maximum length, impedance standards, and the permitted length mismatch in differential pairs or parallel buses. Enter dimensions: Trace width (W) mils. Then. 2H, the formula for the non-embedded. It seems I could largely do without any impedance matching considerations, given what the trace lengths are. The first step is to do a full two-port calibration on the network analyzer. 1. W is calculated to achieve a trace impedance (Z0) of ~50W and S is calculated to achieve a differential trace impedance of 90W. The KiCadPCB calculator is apparently assuming a rectangular trace profile which isn’t quite realistic, particularly with minimal trace clearance values. 25. The trace width (0. Chrome 92. 25mm trace. Following is the formula for differential impedance for a Stripline. Enter your board parameters and get instant results. Description. PCB Trace Impedance Calculator. There are single end trace impedance and distance between traces in the pair. There are four different types of impedance used in characterizing differential trace impedances. Hello Community, iam currently designing a board that contains an 100MBit Ethernet connection. Bus line impedance (Z Bus) Differential Mode line impedance (Z Differential) Common Mode line impedance (Z Common) The Single Line impedance is based on the inductance L and capacitance C per unit length of the trace and can be calculated by the following formula: Below there a few examples where the single line impedance is of interest: Coplanar Waveguide Calculator. Just enter the given values for trace thickness, substrate heights, trace width and subtrate dielectric in the calculator above and press the "calculate" button. 8. Suggested Solution: for 100 Ohm Differential, use half the board thickness and make the tracks equal to the board thickness. 22 mil wide. 2mm from the ground plane below. Disc Air Capacitor Calculator; Impedance Calculator : XL, XC; Inductors, Transformers. This calculator is designed to calculate the characteristic impedance of a microstrip - a flat conductor suspended over a ground plane with a dielectric between them (see diagram below). The answer lies in the spacing between the traces in the pair. Although you'll typically see a 34 Ohm or 40 Ohm single-ended trace impedance value in many designs, some modules will support as high as 50 or 60. 6mm) That should give the traces around 90 Ohms differential impedance according to the PDF, but when I try to input it to my impedance calculator (Saturn PCB toolkit V7. For example, a single 0. Just as important as determining an appropriate trace width for a single-ended trace is determination of an appropriate spacing between two traces in a differential pair. Impedance captures the real and complex. Altium Designer’s differential line impedance calculator will set up your impedance-controlled differential pair routing widths for you. 5. Build a model from experimental data of impedance vs. Use several of them and compare.