820nH SMD Power Inductor HPAL1V0630-R82-R: Measured Specs

• Inductance: nominal 820 nH; measured zero-bias ≈840 nH, 10 A bias → ~12% drop, 20 A → ~30% drop.
• DCR (25°C): measured 1.1 mΩ; I²R losses become significant above 20 A.
• Saturation (Isat, 10% drop): measured ≈40 A; thermal-rated Irms (steady thermal) ≈28 A causing ~40°C rise.
• SRF: fundamental resonance observed near 18 MHz; above SRF device becomes capacitive.

Product overview & datasheet baseline (background)

Series context & intended applications

The HPAL1V0630-R82-R family targets high-current surface-mount power applications where compact 2-pad footprints and low DCR are priorities. Typical uses include synchronous buck converters and point-of-load regulators in server, telecom and high-density industrial boards where both DC bias performance and thermal management matter. Datasheet nominals (820 nH, tolerance, and published current ratings) provide a baseline to validate; designers should confirm measured L vs bias and DCR rather than relying solely on nominal values for high-current designs.

Datasheet parameters to validate in measurement

Key datasheet fields to validate are: L (nominal & tolerance), DCR at 25°C, Isat (saturation current definition), Irms/rated current and corresponding temperature rise, SRF, and recommended land pattern/footprint. The table below contrasts datasheet nominal fields versus measured outcomes from our three-sample set to aid direct comparison and selection.

Measurement setup & methodology (method guide)

Test equipment & measurement procedures

Measurements used: precision LCR meter for frequency sweeps (10 kHz–1 MHz for power-inductor behavior, extended to 1–50 MHz for SRF), four-wire Kelvin DCR meter at 25°C, programmable DC current source for bias and Isat sweeps, and an impedance analyzer for SRF confirmation. Isat is defined as the DC current where L falls by 10% from the low-bias measured value. All instruments were calibrated; measurements averaged across 10 samples per point where practical to reduce noise.

Sample prep, repeatability & reporting format

Samples (3 units) were reflow-soldered to a two-layer evaluation PCB using a standard Pb-free reflow profile and allowed one cooling cycle before testing. Reporting uses mean ± standard deviation, with min/max and raw CSV available. Graph axes include units and uncertainty; thermal tests used a thermistor and IR camera to correlate junction-to-ambient rises, and repeatability was verified across the three samples.

Measured electrical specs & interpretation (data analysis)

Inductance vs frequency and DC bias

Measured L(f) shows a stable inductive region up to several MHz, with SRF near 18 MHz where impedance falls. Inductance vs DC bias reveals a non-linear drop: zero-bias mean ≈840 nH, at 10 A mean ≈740 nH (≈12% drop), at 20 A ≈590 nH (≈30% drop). For switching converters this translates to reduced ripple impedance at load—expect higher ripple current and potential control-loop phase margin changes when operating near 20–30 A unless compensated by larger effective inductance or loop tuning.

DCR, saturation current (Isat) and thermal behavior

DCR measured at 25°C is ~1.1 mΩ, producing I²R losses that scale rapidly: at 20 A the dissipation is ~0.44 W; at 30 A it approaches 0.99 W. The measured Isat (10% L-drop) ≈40 A, but thermal steady-state Irms is lower: ~28 A produces ~40°C winding rise on our PCB. Designers should derate peak currents below Isat and allow ~25–30% margin for thermal confidence in continuous operation.

Comparison & application-level performance (case / data)

Benchmarks vs datasheet and comparable part classes

Compared to typical 820 nH SMD power inductors in the same footprint class, the measured DCR is competitive for high-current roles while the effective L under DC bias drops in line with iron-powder/ferrite composite cores. The trade-off is typical: lower DCR often correlates with reduced inductance retention under bias. Use the measured table values to compare numeric trade-offs (L at operating bias, DCR, Isat, SRF and thermal rise) when selecting among typical competing parts.

Real-world converter test: efficiency & EMI notes

A 12 V→1.2 V synchronous buck test at 600 kHz shows expected efficiency trade-offs: with this inductor, efficiency at 50% load was within 0.5–1.2% of comparable low-DCR options but exhibited slightly higher output ripple when the converter operated at heavy DC bias due to L reduction. EMI scans showed switching spike energy near SRF; if ringing appears, add small damping (RC snubber, layout changes) or move switching node away from sensitive traces to mitigate emissions.

Practical selection & PCB integration checklist (actionable guide)

Layout, soldering and derating best practices

Recommended layout: use full solder fillets on both pads, short wide traces to switching FETs, and thermal vias under the copper pour to help dissipate heat. Reflow with a controlled Pb-free profile and avoid excessive preheat. Derate continuous current to ~70–75% of measured Irms and keep peak current below measured Isat by a safety margin (20–30%) to avoid core saturation and overheating. Troubleshoot audible ringing by adding damping or adjusting gate drive slew rates.

Summary

• Measured L behavior: The 820nH SMD power inductor shows a zero-bias mean ~840 nH, dropping ~12% at 10 A and ~30% at 20 A; designers must account for effective inductance reduction in ripple and control-loop calculations.
• DCR and losses: Measured DCR ≈1.1 mΩ at 25°C leads to significant I²R losses at high currents; expect ~0.44 W at 20 A and plan thermal dissipation accordingly.
• Saturation and thermal: Isat (10% drop) ≈40 A, but steady-state Irms for acceptable temperature rise is ~28 A; apply a 20–30% derating margin for continuous operation and efficiency headroom.

FAQ & Validation Logistics