First Power-Up and Debug

Power a board in stages, measure correctly, and monitor temperature.

Before applying power

Inspect the board, check polarized component orientation, look for solder bridges, and measure resistance from each rail to ground. Compare fitted parts with the schematic and bill-of-material variants.

Prepare a bench supply with a cautious current limit. Current limiting does not make the board immune to damage, but it reduces available fault energy.

Staged power-up

1. Power the board without unnecessary external cables.
2. Watch total current immediately.
3. Measure main rails and ramp order.
4. Check clock and reset.
5. Review configuration status.
6. Test the JTAG chain.
7. Load a minimal image that switches only a few outputs.
8. Add peripherals and interfaces one at a time.

If current reaches the limit, a rail is wrong, or a component heats quickly, remove power and find the cause before trying again.

Measuring well

A long probe ground distorts a fast-edge measurement. Use a short connection and measure at the useful point, often near the receiver or supply pin. Observe both the DC value and switching variation.

Temperature

Consumed power becomes heat. Temperature depends on device dissipation, package, board copper, airflow, and ambient temperature. Monitor the FPGA, regulators, and power devices during the most active scenarios.

Keep a bring-up log with voltages, currents, temperatures, configuration versions, and anomalies. It prevents repeated mistakes and makes board-to-board comparison easier.

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