LM137H/NOPB Equivalent & Substitute Parts

Part Overview

The LM137H/NOPB is a linear voltage regulator IC manufactured by Texas Instruments, designed for negative adjustable output applications. This Through Hole mounted device delivers 1.5A output current in a TO-3 package and operates across an extended temperature range of -55°C to 150°C. The part is currently in Active product status with 3025 units in stock.

Substitute parts are identified when design requirements permit alternative configurations or when primary part availability is constrained. The LM137H/NOPB serves as a negative regulator; however, complementary positive regulation solutions and equivalent negative regulation variants exist within the LM1xx regulator family.

Substiute Parts

LM137H/NOPB

Texas InstrumentsIn Stock: 3123LM137H/NOPB Datasheet

Current PartRFQ

LM117H/NOPB

Texas InstrumentsIn Stock: 6775LM117H/NOPB Datasheet

MFR RecommendedRFQ

LM137H

National SemiconductorIn Stock: 3040LM137H Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution logic for the LM137H/NOPB is determined by the following critical parameters:

Output Configuration & Polarity: The LM137H/NOPB is a negative output regulator. Substitutes must maintain negative output configuration to preserve circuit functionality.

Output Current Rating: All qualified substitutes deliver 1.5A output current, matching the primary part specification.

Voltage Range Compatibility: Input and output voltage ranges must align with the -40V input maximum and -1.2V to -37V output range to ensure proper circuit operation.

Package & Mounting: All substitutes use TO-3 package with Through Hole mounting, ensuring mechanical and electrical compatibility.

Temperature Operating Range: Extended temperature operation (-55°C to 150°C) is maintained across all substitutes.

Protection & Reliability Features: Over Current, Over Temperature, and Short Circuit protection are present in all qualified substitutes.

Parameter Comparison

Engineering Selection Recommendations

LM137H (National Semiconductor) - Parametric Equivalent: This part is the direct parametric equivalent to the LM137H/NOPB. It maintains identical electrical specifications including negative output configuration, 1.5A current rating, and -40V to -37V voltage range. Both parts are Active status with ROHS3 compliance. This substitute is suitable for direct replacement in negative regulation applications requiring extended temperature operation.

LM117H/NOPB (Texas Instruments) - MFR Recommended: This part is designated as manufacturer recommended but operates with positive output configuration, making it unsuitable for direct replacement in circuits requiring negative regulation. The LM117H/NOPB is in Last Time Buy status, indicating limited future availability. Selection of this part requires circuit redesign to accommodate positive rather than negative output polarity. PSRR performance is superior at 80dB ~ 65dB compared to 66dB in the primary part.

For applications requiring negative voltage regulation with 1.5A output capacity and extended temperature range, the LM137H from National Semiconductor provides full parametric equivalence with Active product status and continued availability.

Frequently Asked Questions (FAQ)

Q: Can the LM117H/NOPB replace the LM137H/NOPB directly?

A: No. The LM117H/NOPB is a positive output regulator while the LM137H/NOPB is a negative output regulator. Direct substitution would reverse the polarity of the regulated output, causing circuit malfunction. Substitution requires circuit redesign.

Q: What is the difference between LM137H/NOPB and LM137H?

A: Both parts are parametrically equivalent negative adjustable regulators with identical electrical specifications. The LM137H/NOPB is manufactured by Texas Instruments with bulk packaging, while the LM137H is manufactured by National Semiconductor. Both deliver 1.5A output, operate across -55°C to 150°C, and use TO-3 package mounting.

Q: Are all substitute parts available in the same package?

A: Yes. All qualified substitutes use TO-205AD and TO-39-3 Metal Can packages with Through Hole mounting, ensuring mechanical compatibility and identical PCB layout requirements.

Q: What protection features are included in substitute parts?

A: All substitute parts include Over Current, Over Temperature, and Short Circuit protection, matching the primary part's protection specification.

Q: Why is the LM117H/NOPB listed as Last Time Buy?

A: Last Time Buy status indicates the manufacturer has announced end-of-life for this part number. New orders may be accepted for a limited period, but long-term availability is not guaranteed. For new designs, the LM137H from National Semiconductor is recommended as an active product with continued support.

Q: Can I use these substitutes in high-temperature applications?

A: Yes. All qualified substitutes maintain the extended operating temperature range of -55°C to 150°C, suitable for industrial and high-temperature applications.