The Smith Chart graphically maps S11=reflection coefficient= (ZL-Z0)/ (ZL+Z0) to Load Impedance (ZL), normalized to Z0 (source impedance = center of chart). Hello. At some point the amplitude will stay constant. Microstrip Max Current Calculator. Be sure of which one you finally decide to use. 1 of the Microstrip Calculator using H2 in place of h, εr,eff can be computed as specified in Eq. of typical printed circuit board trace geometries. The new version includes: This software is intended to assist with microwave circuit design in predicting the impedance of a circuit made with Rogers High Frequency circuit materials. EEWeb - Electrical Engineering News and Resources. This calculator requires symmetry in the trace widths and location between plane layers. microstrip target impedance: 50 Ω. This can be achieved by regulating the inner and outer diameter of the coaxial cable, along with the. 0300) creates a microstrip line of length 0. 55 GHz for VSWR < 2, which corresponds to a fractional. Microstrip Mitred Bend Formula or Equation. Most RF Coaxial Cables have an impedance of 50 ohms or 75 ohms. In most practical cases, the dielectric substrate is electrically thin, that is, (h ≪lambda). The full structure of the transmission line in microstrip_rlc. Dimensional units: mm mils Zo (single ended impedance, Ohms) = d (trace separation) = h (dielectric thickness) = Zd (Impedance, Ohms) =Calculate Microstrip impedance for given PCB parameters. d – wire diameter. Ensuring impedance-controlled routing also requires knowledge of the substrate’s dielectric constant and your required trace width. Line Thickness (T) in mils. The length of the net is important for impedance matching and minimising propagation delay. *Accurate for arbitrary values of Er and w/h ratios. Microstrip line impedance calculators are useful to some extent, but they have some of their downsides, so it is very necessary to use some up-to-date modern tools for calculations. LC Impedance matching network designer Enter the input and output impedances to be matched and the centre frequency. Coplanar Waveguide Calculator. A coil inductance formula is based on the basic loop inductance. These values are trace width, substrate heights, substrate dielectric, and trace thickness. Here lies the challenge: impedance calculators must balance speed and accuracy. Use lineleng to calculate the phase shift of a reflection coefficient for line lengths of d=0, 1/8, 1/4, and ½ wavelengths. The impedance Z 0 of a transmission line consisting of a circular signal conductor having a diameter d and centered between parallel ground planes separated by a distance h is given by: Eq. These properties can be useful for making fine adjustments to a microstrip design. A simple microstrip is located on the top of the board, while an embedded microstrip is located inside the board substrate as illustrated below. This is a required field. Rho: Conductor resistivity relative to copper. The PCB designer must ensure that its characteristic impedance has the desired value. Reset. Visit to learn more about our other electrical engineering tools and resources. This calculator is designed to calculate the characteristic impedance of a broadside couple stripline (see diagram below). where R0 and X0 are the real and. The required values are trace thickness, substrate heights, trace width, and subtrate dielectric in the calculator above and press the "calculate" button. 8 , Guide wavelength= 0. 2. View Notes. This Mantaro calculator tells me. RF calculations and RF conversions include metric. 5. This means that on each side of the feed line there should be a distance of 1/2 the microstrip width on each side of the microstrip between the microstrip feed line and the patch antenna. 4. 4. The microstrip line is one of the most popular choices of transmission lines in microwave and RF circuits. 6 mils line width, and the effective dielectric constant is 6. 5 mil and the impedance value is only affected typically by 2 ohms. The Pi match circuit is so named because the circuit topology can resemble a pi symbol. Malcolm White. A. g. Modeling approximation can be used to design the microstrip trace. Equation 11. 98 * 1 / 2) / sqrt(4. Change W (line width) to 3. An edge couple differential microstrip transmission line is constructed with two traces referenced to the same reference plane. Both formulas of the dielectric, as well as the total losses, agree. We recommend the software from Polar Instruments if you want to get exact impedance calculation. There is a way of reducing the characteristic impedance of microstrip lines so that miniaturized ƛ/4 microstrip line-based stepped impedance resonator filters can be realized. Most importantly, it computes the critical length of the trace. Use an online differential microstrip impedance calculator; Use an online differential stripline impedance calculator The lateral dimensions, however, are well controlled being photolithographically defined and then etched. The complex characteristic impedance is given by the equation: Z 0 = R 0 + j X 0. Re: Z0 with ADS dear all thanks for your support, i am uploading little image of a microstrip line which is according to line calc has 25ohm impedance, the termination are of 50ohm, now as i said earlier i am getting 0. View All Tools. Adjust the distance "s". I have been fiddling around with GPS antenna trace impedance matching. Asymmetric Stripline. Rectangle Loop Inductance Calculator. coupledmicrostrip = coupledMicrostripLine creates a default coupled microstrip transmission line with a Teflon substrate and default properties for a resonating frequency of 1. With t = 35 um (typical for copper with plating on a pcb), Z odd drops to 44 ohms, according to LineCalc. This microstrip impedance calculator gives you a good start for estimating the trace width and PCB dielectric thickness that will produce a target impedance value. Edge Coupled Microstrip Impedance Calculator This tool helps calculate the impedance of an edge-coupled microstrip. Based on the assessment in the Polar Instruments article, Wheeler’s method appears to be the most accurate method for calculating microstrip. Just enter the given values for trace thickness. Imagine that I need to have a 50 ohms impedance in a PCB trace. Characteristic Impedance and Calculation Formula of Microstrip Antenna . Useful converters and calculators. Edge-Coupled Traces. Coil Inductance Calculator. dual or asymmetric stripline microstrip calculator to find the impedance of printed circuit boards of a known dielectric constant of material, using javascript language. If the ratio (L/W) is close to unity, the radiation pattern will be symmetric but may not provide a resonable input impedance. Note: The results are only for approximation and rough estimation, the final values and the. Use an online differential microstrip impedance calculator; Use an online differential stripline impedance calculatorThe lateral dimensions, however, are well controlled being photolithographically defined and then etched. 109-115, November 1989. Stripline Calculator. 6 ohms and Z even = 110 ohms for your geometry, very close to your result. The Calculator Calculates the values of the Characteristic Impedance, Capacitance per unit length and propogation speed. Differential Microstrip Impedance From Zo. 0; 1 < εr < 15 ) Select the units for all dimensions: mm mils. The accuracy of the equations was observed to be slightly better for higher permittivities. Electronics and Electrical Engineering Tools. Enter the Height, Width and Permittivity to get the Impedance of the Microstrip Note : The unit of the height and width entered must be the same. The patch cutout for the feed inset should be > 2 times the microstrip width. All About Circuits is the largest online electrical engineering communities in the world with over 700K engineers, who collaborate every day to. Click the button corresponding to the characteristic impedance to calculate its value. Microstrips (Source: Max Maxfield) In order to fine-tune the transmission line properties of the microstrip, we need to calculate the impedance of the trace. Once you have the reflection coefficient, you can use it to calculate the S-parameters by comparing with your feedline impedance. As seen here:Figure 3. The ratio of cross-hatch conductor width (HW) to cross-hatch pitch (HP) plays an important role while characterizing the cross-hatch plane. STRIPLINE CALCULATORS, APPLETS, ANIMATIONS & SIMULATIONS. Input w, and click on [ Analyze ] button. Impedance calculation. Relative Dielectric Constant ( εr ): Track Width: mm. Substrate Height (H) in mils. 946 for silver, or 1. Resistance in mOhm/inch. The phase is mostly + 90 ∘ or − 90 ∘, indicating that Zin is mostly reactive. These calculators will return an impedance value for pairs of trace width, substrate thickness, and copper weight values. Enter the values of trace width (w), trace thickness. There are four different types of impedance used. 50Ω. The use of a standardized impedance makes RF design much more practical and efficient. Γ0 = Z01 − ZS Z01 + ZS Γn = Zn + 1 − Zn Zn + 1 + Zn ΓN = ZL − Z0N ZL + Z0N. Backwards crosstalk creates a pulse width that is twice that of the propagation time of the pulse traveling the coupling distance. Edge Coupled Stripline Differential Impedance Calculator. 1 High Impedance; 4. 035 mm) h is the Thickness of dielectric. A Clemson ECE635 Project by Adam Schreiber and Jason Byers. Wire Microstrip Impedance Calculator. 1 Microstrip Line in the Quasi-TEM Approximation; 4. 06228 [dB] keven = 3. Using online calculators, I figured out the width of the PCB trace to create an impedance of 50 Ohms is 2. Following equation or formula is used for Differential Microstrip Impedance Calculator. Microstrip Impedance Calculator Provide values for three of the four parameters H, T, W, Z 0 and the relative permittivity of the dielectric. Microstrip Impedance Calculator Enter the Height, Width and Permittivity to get the Impedance of the Microstrip Note : The unit of the height and width entered must be the same. Don’t forget to check out our other. **Note: Like our stripline impedance calculator, all of our RF calculators allow SI prefix input. Coplanar wave guide. I have a question. FDTD simulation setup. The characteristic impedance (Z o) of a microstrip transmission line can be calculated using the active calculator or the formula at the bottom of the page. ±1% in h, ±2% in ±1% in C. 60. Note the stub is attached in parallel at the source end of the primary line. A matching network optimizes the transfer of power from a source to a load by maximizing the power delivered to the load while meeting other performance specifications. 8. 3. Impedance Calculator Talk to a Sierra Circuits. 3: Normalized characteristic impedance and normalized effective permittivity of a microstrip line as a function of u = w / h. To calculate this, you need some values. This online microstrip impedance calculator calculates the characteristic impedance of the microstrip (Ω), W/H ratio, and effective dielectric constant (εe) by entering the value of dielectric material relative permittivity (εr), the width of the copper trace (W), and dielectric height (H). This online microstrip impedance calculator calculates the characteristic impedance of the microstrip (Ω), W/H ratio, and effective dielectric constant (εe) by entering the value of dielectric material relative. Increasing H increases Zo. Be aware that there are many microstrip impedance calculators on the Internet that give sometimes widely varying results. 2. If you're trying to get your own pcb design project , you should use this tool. 76mm Rogers4350B substrate at a certain frequency and with 35 micron copper thickness, line width becomes 0. The trace resistance of a microstrip is important in determining how much power it dissipates. The stepped-impedance lowpass microstrip filters, which use a cascaded structure of alternating high- and lowimpedance transmission lines. This tool is designed to calculate the inductance introduced by an edge-coupled trace. For 25 ohms, we calculate 31 mils line width and 7. The parasitic capacitance and inductance created by nearby conductors. These lines are considerably shorter in length than the design wavelength and act as semi-lumped elements. Microstrip impedance calculator Mixer spur calculator mmWave Link Budget calculator Noise Figure/Temp converter Optimal Mitre calculator Path loss calculator. Can anyone explain this discrepancy? 1. Loop Inductance Calculator. Such a stripline is constructed with two traces referenced to the same reference planes above and below the traces with a dielectric material between them. fsp is composed of two metal traces and a lumped RLC element 2 mm long placed in between; the metal traces and the substrate have the same properties as in the FDE simulation. Coplanar Waveguide With Ground Characteristic Impedance Calculator. Input w, and click on [ Analyze ] button. Checking Impedance in Your PCB Layout. Calculate Microstrip impedance for given PCB parameters. To use this tool, enter the trace width, thickness, ambient temperature, temperature rise, and the microstrip length and click the "calculate" button. If you need to find and use an efficient and accurate microstrip impedance calculator that provides lossless impedance values, you can use our free tool below. Z diff = 2 * Z o ( 1 – 0. transmission line types. Minimum PCB Trace width with SMD components and. This calculator provides accurate microstrip transmission line analysis and synthesis. Provide values for H, T, W and the relative permittivity of the dielectric and click the button corresponding to unknown parameter Z o to calculate its value. Following is the list of useful converters and calculators. 2. 1. Patch antenna online calculator. Microstrip lines are used to convey microwave -frequency signals. Capacitance in pf/inch. There are a number of pcb transmission line typologies. 9, h = 0. The characteristic impedance of “narrow” ( W ≪ h) microstrip line can be roughly approximated by Equation 7. Designers need numerical tools and the correct analytical formulas to calculate the inductance of their PCB traces. A cross-section of a microstrip transmission line is shown below. Calculate Z 0 as normal Microstrip, until you get the desired value, e. Wire over Ground Calculator. 1< w/h < 3. Microstrip is a type of electrical transmission line which can be fabricated with any technology where a conductor is separated from a ground plane by a dielectric layer known as "substrate". 29 mm width traces to obtain 100 Ohms ZDiff while using 0. eu. This assumes ~0 trace thickness. There are a lot of online trace impedance calculators specifically designed for differential traces. TransCalc is an open-source impedance calculator of various transmission lines based on common closed-form approximations. ZigBee. 96D/H) Zo = Single Ended impedance. A major advantage of a radial stub is that the input impedance presented to the through line generally has broader bandwidth than that obtained with the. Useful converters and calculators. 2) * (1 + 0. 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). Log-Log Graph Paper (PDF Download) Semi-Log Graph Paper (PDF Download) Smith. Radio Frequency Engineering Calculator. It is a useful tool in the design and analysis of microwave circuits, particularly in the fields of communication, radar, and satellite systems. The original source of formula is IPC-2141: Controlled Impedance Circuit Boards and High-Speed Logic Design, April 1996. EEWeb offers a free online microstrip crosstalk calculator. WILKINSON POWER DIVIDER CALCULATOR. The coax is a good way to create a transmission line. 04 in the ε eff. A microstrip width calculator can calculate the width of a microstrip. 5. To use these to design for a target impedance, simply cycle through various geometric values for the trace width until the calculator returns the target impedance. Incidentally, the trace thickness parameter does have a significant effect. Input the parameter of the circuit board and center frequency. The microstrip patch antenna calculator determines the length (L) and width (W) of a rectangular microstrip patch antenna for a given resonant frequency or vice versa. The next graph investigates this further. 48 e-0. This calculator determines the impedance of a symmetric differential stripline pair. One challenge in designing PCB interconnects is maintaining system impedance while reducing crosstalk, which requires reducing trace inductance. Click the button corresponding to the. We are now ready to calculate the microstrip characteristics. This coupling is one of the features of differential traces. Coax Impedance (Transmission Line) Calculator. Microstrip is a single trace on the top layer, with no ground close to it on the same layer. Using this formula, you can calculate the characteristic impedance of a. Dielectric Thickness: mm. Click the button corresponding to the. 2 of the Microstrip Calculator, h=H1 and b=H2-H1. ( 0. might have been the test equipment calibration, impedance mismatch amongst the measurement system’s cables and adapters, or trace impedance errors resulting from structural defects in the etched microstrip lines. Embedded Microstrip Impedance Calculator Microstrip Impedance Calculator Dielectric Thickness (mils) C Dual Stripline Impedance Calculator Asymetric Stripline Impedance Calculator Zo Equation: IPC-D-317A (Eq. With our handy calculator, you can choose from 50 Ohm, 75 Ohm, 93 Ohm and 95 Ohm coaxial cables. The inductance of a PCB trace determines the strength of any crosstalk it will receive. As seen from the formula when D decreases, while keeping H constant, Zdiff decrease. In this calculator, the quasi-static characteristic impedance without taking into account the frequency dispersion is calculated using the. For budgetting reasons I'm tied to a stock pooling layer stackup, so I went for OSHpark's 4-layer stackup (35um copper - 0. could someone point me towards reliable and proven method to calculate impedances for edge coupled differential microstrip?From here, we can see that there are specific stack-ups where a CPW and a microstrip/stripline will have 50 Ohm impedance and the same trace width, even though the ground clearance is quite close clearance to the trace in the CPW. This parameter is used for the loss calculations. Impedance (Ω): The desired impedance. Following equation or formula is used for Microstrip Width Calculator. 5 resin). 5. Modeling approximation can be used to understand the impedance of. 5. Input the parameter of the circuit board and center frequency. 1. In order to obtain the maximum energy transmission, the microstrip line needs to achieve impedance matching with both ends. JLCPCB Impedance Calculator. Most RF systems are built around 50 Ω impedance. One commonly used formula for calculating the characteristic impedance of a PCB trace or transmission line is the capacitance per unit length formula: Z0 = 1 / (C / L) where Z0 is the. Description. In this example, the characteristic impedance of the microstrip transmission line is controlled through the trace’s width. Description. Finally, there is a bandwidth that can be defined in the frequency domain (units of Hz). The websites associated with hits 2-5 all calculate the microstrip impedance for this stackup to be 50. Note: Units do not matter for this calculation as long as they are consistent. Units do not matter as long as they are consistent. Matching T Attenuator A two part calculator which gives ideal and preferred value resistors, showing most formulas used and a link to the others. Microstrip impedance shall be calculated according to above Eq. 5mm, T=0. Let’s start new project together!. This calculator is heavilly based on . 6 GHz. Such a microstrip is constructed with two traces referenced to the same reference plane with a dielectric material between them. Atwater, “Simplified Design Equations for Microstrip Line Parameters”, Microwave Journal, pp. HFSS Waveport Size Calculator Figure out the correct waveport size to use in HFSS for a microstrip line feed. To use these to design for a target impedance, simply cycle through various geometric values for the trace width until the calculator returns the target impedance. Atwater, “Simplified Design Equations for Microstrip Line Parameters”, Microwave Journal, pp. The edge couple differential microstrip transmission line is a common technique for routing differential traces. A cross-section of a microstrip transmission line is shown below. These tools seamlessly integrate with the rest of your design tools in a. Microstrip patch antenna input impedance in the fundamental mode (i, j, k) = (1, 0, 0). These are considered to be standardized impedance values with cables readily available. SAVE & ACCEPT. Figure 24. 635 mm, W = 0. Microstrip Calculator computes a microstrip's height/width ratio, impedance and relative dielectric constant for a microstrip transmission line. Instructions are below the calculator and don’t forget we can make and test your controlled impedance printed circuit board too. Pasternack's RF calculators and conversions section provides engineers valuable and easy-to-use tools ranging from complex mathematical formulas to simple conversions. Inputs Trace Thickness Substrate Height Trace Width Trace Spacing Dielectric Constant Outputs. 2. 1 er 15 Note that 1. g. Wavelength Calculator. A simple microstrip is located on the top of the board, while an embedded microstrip is located inside the board substrate as illustrated below. A coplanar waveguide calculator will operate in one of two ways. 6 Ω and ε e = 6. Coplanar Waveguide Calculator. Values for L and C will be calculated for the four. Modified 1 year, 4 months ago. a) The effective relative permittivity of the substrate. 45 for gold. The inductance of a rectangle loop has three geometric variables: W – rectangle long side. This allows you to double check the calculator and make sure that it selected appropriate values, by making sure the impedance correctly matches the input impedance. Assume microstrip line for which propagation occurs with. 5 / 2) Zo = 64. 6 mils line width, and the effective dielectric constant is 6. 7. *Solder resist PCB coating will have the effect of lowering the impedance (due to the 30um or so of Er 3. Polar or rectangular grids only allow direct reading of S11. There are four different types of impedance used in characterizing differential trace impedances. Edge-Coupled Microstrip. EEWeb offers a free online broadside coupled stripline impedance calculator. The characteristic impedance is given by: Eq. Symmetric Stripline Impedance Calculators and Formulas; To really see how the trace widths for these transmission lines compare, we need to plot the characteristic impedance vs. 32 and the equation shown in 5. t is the Thickness of track (1 oz/ft2 = 0. Agilent's LineCalc tool calculates Z odd = 50. The wire microstrip transmission line is similar to a standard microstrip transmission line, but with a round conductor. Some calculators opt for Wadell's results, yet they simply state they are "based on Wheeler’s method" without providing references. There are many calculators available online, as well as built into your PCB design software. This calculator will help you calculate the guided wavelength, provided the dimensions of the microstrip are given as well as the velocity of propagation, the microstrip material's dielectric constant, and the input frequency. The KiCad PCB Calculator is a set of utilities to help you find the values of components or other parameters of a layout. The Calculator assumes that 1. 1: Impedance-matching using a quarter-wavelength transmission line. The plots show the magnitude and phase of the input impedance. trace is typically quoted as being 5 to. Tuning for your traces to the desired impedance value occurs by adjusting trace width and distance from the reference plane. This transmission line calculator was. This is actually a general way to express impedance, but it requires an understanding of complex numbers. Microstrip Transmission Line Models. The calculator produces more accurate results than the IPC formulas for impedance because it implements a more. Sorted by: 1. Note: All dimensions are in mils. If the ratio of line width to substrate thickness is w/h = 4. A helpful tool for calculating the impedance of a wire microstrip. Inductance of microstrip lines Microstrip lines used as shunt inductors Application Note AN258, Rev. 2. 1 (a). Calculate Coplanar impedance for given PCB parameters. Then Rock'n'Roll. Microstrip impedance calculator Mixer spur calculator mmWave Link Budget calculator Noise Figure/Temp converter Optimal Mitre calculator Path loss calculator. 8. It renders fairly accurate results suitable for use in circuit board manufacturing and engineering analysis. . Coplanar waveguide characteristic impedance calculator. There are four different types of impedance used in characterizing differential trace impedances. This is the reason why engineers specify the trace width in their designs. 39 for the effective dielectric constant. 352278 [-] coupling =-9. Following equations or formula are used for this microstrip patch antenna calculator. For this reason, trace width is important in the design of striplines. D = trace edge to edge spacing. Reset. dBm to Watt converter Stripline Impedance calculator Microstrip line impedance Antenna G/T Noise temp. Before, working with a trace impedance calculator, one should be aware of which equations the calculation uses. Read the latest Microstrip Crosstalk Calculator forum discussions in the electronics and electrical engineering communities. Differential Impedance Calculator. In fact, striplines often make components such as band-pass filter's more accurately, with more symmetric roll-off and no lower cutoff frequency. It is important to note that in industry we can find that some differential pairs are routed this way for a strong coupling, but. This tool is designed to calculate the resistance of a microstrip trace with a copper conductor. 6. 1. Useful converters and calculators. Use this user-friendly online calculator to calculate the impedance, capacitance, propagation delay, and inductance of a Microstrip Line on a Printed Circuit Board (PCB). Figure 5. In design, the physical dimensions must be determined given the desired electrical properties. Stripline Trace. The input impedance depends upon the. "Controlled impedance from the fabricators view", Rick Norfolk, p. New Online Microwave Impedance Calculator. *Solder resist PCB coating will have the effect of lowering the impedance (due to the 30um or so of Er 3. This tool calculates the matching network necessary to terminate a line of the specified characteristic impedence (Z o) in a specific complex load impedence (R L + jX L) at a specified frequency. At low frequencies near 0 GHz, the input impedance is inductive since. 6 as magnitude of S11 instead of 0. Provide values for three of the four parameters h, t, w, Z 0 and the relative permittivity of the dielectric. The impedance of a differential via pair cannot be treated with a single via impedance calculator unless the vias are spaced far apart. Click the button corresponding to the unknown parameter to calculate its value ( 0. Traces in printed circuit boards can often form broadside or edge pairs and may introduce unwanted inductance. The dielectric material and the air above the microstrip makes it a transmission line with the inhomogenous dielectric. When cascaded with high impedance quarter-wavelength transmission lines, the radial stub can provide an effective decoupling network for microwave. The differential signals have a differential characteristic impedance. Try This New Tool. Microstrip Patch Antenna Calculator Formula. The calculator then uses a formula to calculate the width and spacing of the trace or transmission line required to achieve the desired characteristic impedance. 1t for W/h ≤ 1 and Wr = W + 1. 0; 1 < ε r < 15 ) Select the units for all dimensions: mm mils. Need Help to calculate input and output impedance of this amplifier: Homework Help: 11: May 26, 2023: How to calculate the input current through my buck converter? General Electronics Chat: 5: Dec 20, 2018: Can You Calculate The Input Impedance? General Science, Physics & Math: 27: Dec 3, 2018: A: How to calculate. Go to our microwave calculator page, our microstrip calculator does this calculation for you! It's time for a Microwaves101 Rule of Thumb! For pure alumina (ε R =9. Note that if the wire is insulated, then the results of this calculator will just be an estimate. to NF. Coil Inductance Calculator. icrostrip line: H. Height. The T match circuit gets its name because the circuit topology looks like the letter “T”. In fact, striplines often make components such as band-pass filter's more accurately, with more symmetric roll-off and no lower cutoff frequency. 6 Band Resistor. Equation Source: Ulaby "Fundamentals of Applied. Incidentally, the trace thickness parameter does have a. I've tested now several, because the first two did show a huge difference in the calculated impedance for a CPW waveguide on silicon, with exactly the same parameters (dieletric constant, geometry etc). 6 Band Resistor. When I google “impedance calculators pcb” this website is the first hit. 3 shall be used. 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 . Created: 16 October 2022.