Power Integrity Simulation and Review

Flux is an AI hardware engineer. It simulates power delivery and heat on your PCB and reviews the results.

Analyze PDN impedance

Ask Flux to plot power delivery network impedance across a frequency range.

Plot PDN impedance from 10 kHz to 100 MHz for the 1.2 V rail.

Analyze the power delivery network across this frequency range and report impedance peaks.

Plot the impedance of each power rail and identify plane resonance.

Analyze the PDN using the vendor models for the capacitors.

Flux returns a PDN impedance plot over the frequency range you specify. The analysis can use vendor capacitor models with equivalent series resistance (ESR) and equivalent series inductance (ESL).

Choose decoupling capacitors for a target impedance

Ask Flux to select decoupling capacitors for a rail and target impedance.

Choose decoupling capacitors for a 50 milliohm target impedance on the 1.2 V rail.

Select capacitors that meet the target impedance across this frequency range.

Review the existing capacitors and choose changes to meet the PDN target.

Use the vendor capacitor models, including ESR and ESL, to choose the decoupling capacitors.

Name the rail, target impedance, and frequency range. Flux uses the capacitor models to choose decoupling capacitors for the target.

Measure load-step droop

Ask Flux to simulate a load step on a rail and report its voltage droop.

Simulate a 3.3 V rail load step from 0.5 A to 2 A and report voltage droop.

Measure the transient droop on the 1.2 V core rail when the processor load changes.

Compare rail droop before and after the decoupling capacitor changes.

Report the peak droop and recovery time for this load step.

Give Flux the rail and load conditions. Flux returns the load-step transient and the voltage droop.

Calculate IR drop under load

Ask Flux to calculate IR drop on power planes and traces under the stated loads.

Calculate IR drop on the 5 V plane and traces at a 2 A load.

Analyze voltage drop on each power rail with these component currents.

Find the board areas with the greatest voltage drop under full load.

Compare IR drop before and after widening the power traces.

Flux calculates IR drop on planes and traces under the load conditions you provide.

Review power budgets by rail

Ask Flux to calculate the power budget for each rail.

Calculate the power budget for each rail from the component loads.

List the current and power budget for every supply rail.

Compare the rail budgets with the loads in this design.

Update the power budget after I change the motor driver and sensor.

Flux reports the power budget per rail. Use it with the load conditions for the PDN, droop, and IR-drop analysis.

Set trace width for current

Ask Flux to calculate trace width from current and current density.

Calculate the trace width for a 3 A power path.

Review the current density on the battery and motor supply routes.

Set the copper width for each rail from its current requirement.

Widen the power traces to meet the required current density.

Flux calculates trace width for the current and current density. It can use the result to set or update the copper width.

Analyze PCB temperature

Ask Flux to simulate component temperatures and create a heat map.

Estimate PCB temperatures at 12 V input and 1.5 A load. Show component temperatures and the heat map.

Find the hot spots on the board when the regulator dissipates 1.5 W.

Compare the component temperatures before and after widening the power copper.

Run a thermal simulation with the operating conditions for this board.

Flux reports component temperatures and a summary heat map. Give Flux the board's operating conditions or the dissipated power for each component.

Review power integrity with Flux

Ask Flux to run power and thermal simulations, review the results, and fix the issues it finds.

Review power integrity on this board. Run PDN, load-step, IR-drop, and thermal simulations, then fix the issues you find.

Check the 1.2 V rail against its target impedance and add or move decoupling capacitors as needed.

Review the current density and widen copper or add vias where needed.

Compare the rail droop and component temperatures after the changes.

Flux reviews PDN impedance, rail droop, IR drop, plane resonance, current density, and temperature. It can add or move decoupling capacitors, widen copper, and add vias to fix issues.

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