Please enter all required values.
RESULTS
Input Parameters Specification
Trace ThicknessCopper thickness of the embedded conductor. Thickness changes effective geometry and can shift controlled impedance.
Height 1Distance from lower plane to trace. This is the base microstrip height used first in the preserved calculation logic.
Height 2Distance from lower plane to upper reference level. It controls how much dielectric cover exists above the embedded trace.
Trace WidthWidth of the embedded microstrip conductor. Wider traces generally reduce impedance.
Dielectric ConstantRelative permittivity of the PCB dielectric material. Higher dielectric constant usually lowers impedance.
OutputCalculated embedded microstrip impedance in ohms for RF PCB and controlled-impedance stackup checks.
Practical Operational Examples
Controlled Impedance PCB
Estimate impedance for embedded traces inside multilayer PCB stackups used in RF and high-speed routing.
RF Stackup Design
Adjust H1, H2, width, thickness and Er to tune the trace impedance before fabrication.
Buried Signal Routing
Use this when a trace is below the surface dielectric cover instead of exposed like a standard microstrip.
Manufacturer Review
Compare early calculator results with PCB house stackup data before ordering controlled impedance boards.
Diagrams & Theory
An embedded microstrip trace sits inside the dielectric below the top surface and above the bottom reference plane. H1 and H2 define the trace position inside the PCB stackup.
Formulas & Mathematical Logic
The calculator preserves the supplied embedded microstrip JavaScript formula and unit multipliers.
Step 1: Convert trace thickness, H1, H2 and trace width using the selected unit multipliers.
Step 2: First calculate normal microstrip impedance using H1, trace width, trace thickness and dielectric constant.
Step 3: Cover height = H2 - H1.
Step 4: If cover height is lower than zero, impedance becomes zero as in the original source logic.
Step 5: If cover height is valid, embedded-height correction is applied using exp(-2 × cover / H1).
Step 6: Final impedance is displayed in ohms.
Step-by-Step Example
Example: trace thickness = 1 mil, H1 = 8 mil, H2 = 20 mil, trace width = 10 mil, dielectric constant = 4.2.
The calculator converts all geometry values using the selected unit multipliers.
A base microstrip impedance is calculated from trace width, thickness, H1 and dielectric constant.
Cover height is calculated as H2 - H1.
The embedded correction factor is applied to the base impedance.
The final embedded microstrip impedance is shown in ohms.
How to Use This Calculator
Enter the copper trace thickness and select the correct unit.
Enter Height 1 from lower reference plane to the embedded trace.
Enter Height 2 from lower plane to upper reference level.
Enter trace width and select the correct unit.
Enter dielectric constant of the PCB material.
Click Calculate to get embedded microstrip impedance.
About This Calculator
Estimate impedance for embedded PCB microstrip traces inside a dielectric cover.
The CalcBoy Embedded Microstrip Impedance Calculator calculates characteristic impedance from trace thickness, H1, H2, trace width and dielectric constant.
An embedded microstrip is different from a normal surface microstrip because the trace is not fully exposed on the outer layer. It is placed below a dielectric cover while still referenced to a lower plane. This geometry appears in multilayer RF boards, controlled-impedance digital routing, buried signal traces, and PCB stackups where a signal trace is covered by solder mask, prepreg, or another dielectric layer.
The key difference is that H1 defines the base distance from the trace to the lower reference plane, while H2 defines the upper reference or dielectric cover level. When H2 is greater than H1, the trace behaves like a covered or embedded microstrip, and the impedance is corrected by the original formula logic.
This calculator is useful for RF PCB routing, microwave layouts, high-speed signals, impedance-controlled stackups, prototype boards and manufacturer discussions. For production controlled impedance, always verify the final value with the PCB manufacturer’s stackup, dielectric tolerance, copper plating, solder mask data and impedance test coupons.
Best UseEmbedded microstrip impedance checks for multilayer PCB stackups.
Supported InputsTrace thickness, H1, H2, trace width and dielectric constant.
Helpful ForRF traces, high-speed signals, buried routing and controlled impedance nets.
Design ReminderUse real PCB stackup data for final impedance confirmation.
Tip: If the trace is covered by dielectric, do not treat it exactly like an open surface microstrip. Embedded cover height can shift impedance noticeably.
Frequently Asked Questions
What is embedded microstrip impedance?
It is the characteristic impedance of a PCB trace that behaves like a microstrip but is covered or embedded inside dielectric material.
What are H1 and H2?
H1 is the base height used for the trace-to-reference-plane distance. H2 defines the upper reference or dielectric cover level used for embedded correction.
Why does dielectric cover affect impedance?
Cover dielectric changes the electric field distribution around the trace, which can shift impedance compared with an uncovered microstrip.
Can I use this for RF PCB design?
Yes. It is useful for RF and high-speed PCB stackups where the trace is covered or embedded.
What happens if H2 is lower than H1?
The original source logic sets impedance to zero when cover height becomes negative.
Can this replace PCB manufacturer impedance control?
No. Use it as an estimate and verify final values with your PCB manufacturer’s controlled-impedance stackup.
Related Calculators
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Symmetric Stripline Impedance CalculatorCalculate centered stripline impedance for multilayer boards.
Microstrip Wavelength CalculatorCalculate guided wavelength and effective dielectric constant.