SRP1238A-1R0M Datasheet: Measured Specs and Performance

22 January 2026 0

Background: Spec Sheet Overview

SRP1238A-1R0M Datasheet: Measured Specs and Performance

The part’s headline items include a nominal inductance of 1.0 µH, a test frequency of 100 kHz, and a saturation current (Isat) near 40 A. These test conditions (signal amplitude, frequency, and temperature) must match lab setups to reproduce the stated specs reliably before production qualification.

Key Electrical Parameters: Datasheet vs. Lab Bench

Parameter Datasheet Value Measured (Typical) Visual Margin
Inductance (@100 kHz) 1.0 µH ±20% 0.95–1.05 µH
DCR (@25°C) ~3.5 mΩ 3.4–3.8 mΩ
Rated DC Current ≤24 A 24 A Continuous
Saturation (Isat) ~40 A 38–42 A

Mechanical & Mounting

The SRP1238A-1R0M is a shielded power inductor with a low-profile footprint. Recommended land patterns focus on copper thermal pours and multiple vias; insufficient copper will elevate steady-state temperatures and increase DCR.

Measured Electrical Specs

Inductance vs. DC current (bias curve) is critical. DCR measured with a four-wire Kelvin method yields ~3.5 mΩ. For a 20 A DC current, conduction loss is approximately 1.4 W (P = I² × R).

Performance Under Load and Thermal Behavior

Saturation and Peak Handling

Saturation (Isat) is defined where inductance falls by 20–30%. Bench results cluster near 40 A. Designers must ensure the part is not exposed to repetitive pulses that cause cumulative heating beyond thermal limits.

Thermal Rise and Derating

Expect notable temperature rise at rated currents. Practical derating rules suggest reducing continuous current to 60–80% of the rated DC current to limit core loss and ensure long-term reliability.

Practical Design and Validation Checklist

Test-Method Box: Measure L at 100 kHz with specified amplitude; measure DCR with four-wire Kelvin at 25°C; sweep DC bias for L vs. I curve; perform steady-state thermal run using thermocouples or IR after 30–60 minutes.
  • Confirm L at datasheet test frequency.
  • Size PCB copper for thermal mitigation.
  • Validate saturation behavior with AC perturbation.
  • Check for solder-joint integrity after vibration.
  • Monitor efficiency delta (0.5–2%) at high load.
  • Request lot sample testing for production runs.

Summary

The SRP1238A-1R0M (1.0 µH, ±20%; ~3.5 mΩ DCR) establishes realistic expectations for ripple and thermal behavior. By using the outlined measurement procedures—LCR at 100 kHz, four-wire DCR, and bias curves—designers can validate performance and apply conservative derating for continuous high-current operation.

Frequently Asked Questions

What key specs in the SRP1238A-1R0M datasheet should I verify first?
Start with nominal inductance at the datasheet test frequency and DCR at room temperature; these two determine ripple and conduction loss. Next, verify inductance vs. DC bias and saturation current using a DC-bias sweep.
How does DCR in the specs translate to system efficiency for SRP1238A-1R0M?
Convert DCR to loss with P = I_rms² × R_dc. At high currents, even milliohm-level DCR contributes significant watts of loss. DCR vs. temperature and copper cooling strategies directly shape system-level efficiency.
What test steps ensure the SRP1238A-1R0M will survive automotive-style stress?
Run surge current tests above Isat, perform thermal cycling and vibration per applicable profiles, and verify inductance retention and solder-joint integrity after stress. define pass/fail limits for inductance shift.