PM40-R82M Equivalent & Substitute Parts

Part Overview

The PM40-R82M is a 820 nH unshielded molded inductor manufactured by Bourns Inc., rated for 450 mA with a maximum DC resistance of 670mOhm. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. The part is packaged in 1812 (4532 Metric) surface mount format with non-magnetic core construction and operates across the temperature range of -55°C to 125°C.

Substiute Parts

PM40-R82M

Bourns Inc.In Stock: 697PM40-R82M Datasheet

Current PartRFQ

CM453232-R82KL

Bourns Inc.In Stock: 741CM453232-R82KL Datasheet

DirectRFQ

CM453232-R82ML

Bourns Inc.In Stock: 3696CM453232-R82ML Datasheet

DirectRFQ

1812-821K

API Delevan Inc.In Stock: 8641812-821K Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the PM40-R82M is determined by the following critical parameters: inductance value (820 nH), package format (1812 surface mount), current rating capability (minimum 450 mA), and operating temperature range compatibility. The substitute parts are grouped into two categories:

Direct Substitutes (CM453232 Series): These parts maintain the same inductance value, package size, and current rating specifications. The CM453232-R82KL and CM453232-R82ML differ from the original in core material (ferrite drum core versus non-magnetic molded), tolerance grade, and DC resistance characteristics, but remain functionally equivalent within the specified electrical parameters.

Similar Substitute (1812-821K): This part from API Delevan Inc. matches the inductance, package format, and operating temperature range but presents different current rating and DC resistance values, requiring application-level evaluation.

Parameter Comparison

Engineering Selection Recommendations

CM453232-R82ML (Preferred Direct Substitute): This part is the primary equivalent for PM40-R82M replacement. It maintains identical inductance and package specifications with improved current rating (475 mA versus 450 mA) and superior DC resistance characteristics (450mOhm Max versus 670mOhm Max). The part is ROHS3 compliant and carries active product status with substantial inventory availability (3620 Pcs). The reduced operating temperature minimum (-40°C versus -55°C) requires verification against application requirements.

CM453232-R82KL (Direct Substitute with Tighter Tolerance): This variant offers the same electrical performance as CM453232-R82ML with tighter inductance tolerance (±10% versus ±20%), suitable for applications requiring improved inductance accuracy. ROHS3 compliance and active status apply. Lower inventory levels (669 Pcs) may impact procurement timelines.

1812-821K (Similar Substitute with Limitations): This part maintains inductance and package compatibility but exhibits significantly higher DC resistance (1.6Ohm Max) and lower current rating (354 mA). Use is restricted to applications where the original 450 mA current requirement can be reduced and higher resistive losses are acceptable. The part retains the original operating temperature range (-55°C to 125°C) but remains RoHS non-compliant.

Frequently Asked Questions (FAQ)

Q: Can CM453232-R82ML directly replace PM40-R82M in all applications? A: Direct replacement is possible for applications where the operating temperature minimum of -40°C is acceptable. The improved current rating and reduced DC resistance provide performance benefits. Verify temperature requirements before implementation.

Q: What is the primary difference between CM453232-R82KL and CM453232-R82ML? A: Both parts are electrically equivalent with identical inductance, current rating, and DC resistance. The distinction is inductance tolerance: CM453232-R82KL specifies ±10% tolerance while CM453232-R82ML specifies ±20% tolerance. Select CM453232-R82KL for applications requiring tighter inductance accuracy.

Q: Why does 1812-821K have significantly higher DC resistance? A: The 1812-821K uses iron core construction, which results in different electromagnetic characteristics compared to the ferrite core design of the CM45 series. The higher DC resistance (1.6Ohm) reflects this core material difference and limits its suitability as a direct substitute.

Q: Are the substitute parts pin-compatible with PM40-R82M? A: All substitute parts use identical 1812 (4532 Metric) surface mount packaging with the same footprint and pin configuration, ensuring mechanical and electrical compatibility at the PCB level.

Q: What compliance considerations apply to substitute selection? A: CM453232-R82ML and CM453232-R82KL are ROHS3 compliant, addressing regulatory requirements for new designs. PM40-R82M and 1812-821K are RoHS non-compliant and should be avoided in applications subject to RoHS directives.