The HPAL1V0640-R68-R datasheet highlights a compact, high-current molded SMD inductor: 680 nH nominal inductance, ~19 A rated current, low DCR and a two-pad package that fits tight power-rail designs. This article gives an engineer-focused walkthrough of the datasheet, translating headline numbers into actionable selection, test and layout guidance for US applications.
Part Overview & Key Datasheet Summary
Quick specs at a glance
Headline values: nominal inductance 680 nH ± tolerance, rated current ~19 A, SMD 2-pad mounting, typical DCR (low mΩ range), and self-resonant frequency suitable for many switch-mode frequencies. Use these power inductor specs to rapidly screen for buck converters, multiphase rails, and high-current decoupling networks.
- Nominal inductance: 680 nH
- Rated current: ≈19 A
- Package: SMD, 2-pad
- Typical DCR: low milliohm (check datasheet table)
Mechanical footprint & recommended land pattern
The part uses a molded body over two termination pads; footprint dimensions are compact and require accurate pad spacing and solder-paste aperture control. Follow the recommended land pattern for reliable fillet formation—undersized pads or excessive paste cause poor solder joints, elevated thermal resistance, and potential heating or detach under high current cycles.
Electrical Characteristics — Detailed Specs
To accurately assess the performance limits under high-frequency operation, reference the consolidated parameters below:
| Key Parameter | Value / Spec Limit | Test & Operational Conditions |
|---|---|---|
| Nominal Inductance | 680 nH (0.68 µH) | Typically verified at 100 kHz, 1.0 V |
| Rated Current (Irms) | ~19 A | ΔT of 40°C rise from ambient baseline |
| Saturation Current (Isat) | High Peak Capacity | Inductance roll-off limited within 20% to 30% |
| DC Resistance (DCR) | Low Milliohm Range | Measured at 25°C ambient temperature |
Inductance, tolerance & frequency behavior
Inductance is measured at a defined test frequency and current; the datasheet specifies test conditions that affect the quoted 680 nH value. Expect inductance to fall with frequency; review the inductance vs. frequency curve when designing LC filters or predicting ripple. Quote the tolerance in the BOM as the datasheet nominal ± tolerance to avoid procurement mismatches.
DC resistance (DCR), saturation current, and impedance
DCR is given under defined temperature conditions and directly impacts I²R losses and efficiency. Saturation behavior is specified separately from rated current—saturation current indicates when inductance drops significantly under DC bias. Consult the electrical specs tables and curves to understand impedance across frequency and to size copper and thermal margins appropriately.
Thermal, Environmental & Reliability Ratings
Temperature ratings, thermal derating & power handling
Operating temperature range and thermal derating guidance are provided; use I²·DCR to compute steady-state power loss and then apply thermal resistance or empirical delta-T per watt to estimate temperature rise. A conservative derating curve ensures headroom: for continuous currents near rated values plan for reduced allowable current at elevated ambient temperatures.
Soldering, reflow profile and reliability tests
Datasheet reflow profiles and recommended peak temperatures inform assembly parameters; follow the vendor’s maximum soak and peak limits. Typical reliability data include thermal shock, vibration and humidity tests—use these results to assess lifecycle suitability for target applications and to plan additional board-level stress tests when required.
Measurement & Testing Procedures
Measuring inductance and DCR in-circuit vs. on a test board
Measure with an LCR meter using Kelvin probes; for DCR use a milliohm meter with four-wire sensing. Test on a defined PCB test footprint to control parasitics. De-embed board traces by measuring a calibration coupon, subtracting trace inductance/resistance to isolate component values for accurate validation against the datasheet.
Verifying saturation current and thermal behavior
Ramp DC current while monitoring inductance or impedance to locate the saturation point where inductance drops (set the pass/fail at the datasheet’s specified drop, e.g., 10–20%). For thermal tests, apply expected ripple/current profile and measure temperature with thermocouples or IR across steady-state intervals; compare to datasheet ratings and derating guidance.
Typical Applications & Circuit Examples
Buck converters and high-current power rails
For synchronous buck outputs choose the HPAL1V0640-R68-R when 680 nH meets ripple and transient requirements at your switching frequency. Calculate ripple current ΔI = Vout·(1−D)/(L·fsw) and verify peak currents remain below saturation with margin. Tight layout, short loops and thermal vias reduce EMI and temperature rise.
Filtering, decoupling and transient suppression
Use this part for input filters or output LC stages where low DCR and moderate inductance balance efficiency and ripple. Pair with low-ESR ceramics for fast transient response; consider higher-inductance or lower-DCR alternatives if lower ripple or greater saturation margin is required for bursty loads.
Selection, Sourcing & BOM Integration Checklist
Matching part specs to design requirements
Checklist: inductance & tolerance, DCR limit, saturation margin (headroom vs. peak current), thermal derating, footprint verification and packaging. If peak current > 0.8×Isat choose a higher-Isat option. Record the exact datasheet revision in the BOM note for traceability and future cross-references to the HPAL1V0640-R68-R datasheet.
Procurement, footprint verification & build validation
Before final BOM release verify CAD footprint, 3D model, pick-and-place data, and paste stencil apertures. Run a prototype build with thermal and electrical validation tests documented in a validation report. Capture supplier packaging options and MOQ to align procurement timing with production schedules.
Summary
HPAL1V0640-R68-R is a compact 680 nH, ~19 A rated SMD inductor suited for high-current rails where low DCR and small footprint matter. Key design actions are verifying DCR and saturation under expected board thermal conditions, validating solder joint quality, and confirming layout practices to control EMI and losses.
- Designers should validate DCR and I²R losses on a representative PCB to predict temperature rise and derating needs; ensure saturation margin for transient peaks.
- Follow recommended land pattern and reflow profile to avoid solder joint defects and elevated thermal resistance that degrade power inductor specs.
- In buck and filter use-cases, compute ripple and verify ΔI and peak currents vs. saturation; pair with appropriate capacitors for transient and EMI control.
FAQ
What test conditions define the HPAL1V0640-R68-R inductance value?
Inductance is specified at a defined test frequency and test current in the datasheet; verify those conditions when comparing parts. For accurate spec comparison measure on a fixture matching the datasheet test setup or de-embed your board parasitics to avoid misinterpreting in-circuit measurements.
How should I verify HPAL1V0640-R68-R saturation current in the lab?
Ramp DC current while tracking inductance or impedance; the saturation current is where inductance falls by the datasheet’s defined percentage. Use slow ramps with thermal monitoring to separate thermal drift from magnetic saturation, and document pass/fail thresholds in the validation report.
What PCB layout practices minimize heating and EMI for HPAL1V0640-R68-R?
Keep high-current loops short and wide, place the inductor close to switching node and associated caps, and provide thermal vias under pads if allowed by the footprint. Optimize paste aperture and fillet formation during assembly to ensure low thermal resistance and solid thermal conduction away from the part.
What are the typical applications of the HPAL1V0640-R68-R inductor?
The HPAL1V0640-R68-R is ideal for synchronous buck outputs, high-current power rails, input/output filter networks, and multiphase voltage regulator modules (VRMs) requiring low-DCR and robust saturation margin.
