LM109H Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The LM109H is an active linear voltage regulator IC manufactured by Texas Instruments, classified as a Power Management (PMIC) component. It delivers a fixed positive output of 5.05V at 200mA maximum output current in a TO-39-3 metal can package. The device is designed for applications requiring stable regulated power supply with integrated over-current and over-temperature protection. As an active product with ROHS3 compliance and unlimited moisture sensitivity rating, the LM109H remains in production. Substitute parts are identified when inventory constraints, supply chain disruptions, or procurement requirements necessitate alternative sourcing while maintaining identical electrical and mechanical specifications.

Substiute Parts

LM109H

Texas InstrumentsIn Stock: 1376LM109H Datasheet

Current PartRFQ

LM109H/NOPB

Texas InstrumentsIn Stock: 1427LM109H/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LM109H are identified based on strict parametric equivalence across the following critical criteria:

• Fixed output voltage of 5.05V
• Output current capability of 200mA
• Maximum input voltage rating of 25V
• Positive output configuration with single regulator
• TO-39-3 metal can package (TO-205AD supplier designation)
• Through-hole mounting compatibility
• Operating temperature range of -55°C to 150°C
• Integrated over-current and over-temperature protection
• Active product status with current manufacturing availability
• ROHS3 compliance and MSL Level 1 rating

The LM109H/NOPB variant qualifies as a parametric equivalent substitute, sharing identical electrical specifications and mechanical packaging while differing only in lead finish designation (NOPB indicates lead-free plating).

Parameter Comparison

Engineering Selection Recommendations

Both the LM109H and LM109H/NOPB are active products manufactured by Texas Instruments with full ROHS3 compliance and unlimited moisture sensitivity rating. Selection between these parts is determined by lead finish requirements and procurement specifications rather than electrical performance differences.

The LM109H/NOPB variant incorporates lead-free plating (NOPB designation) and is suitable for applications subject to RoHS directives or customer specifications requiring lead-free components. The standard LM109H may be selected where lead-containing finishes are acceptable and inventory availability favors this variant.

Both parts maintain identical electrical characteristics, thermal performance, and protection features across the specified operating temperature range of -55°C to 150°C. PCB layout, thermal management, and circuit design considerations remain unchanged between variants.

Frequently Asked Questions (FAQ)

Q: Can LM109H/NOPB be used as a direct replacement for LM109H?

A: Yes. The LM109H/NOPB is a parametric equivalent with identical electrical specifications, output voltage, current rating, and package configuration. The only difference is the lead finish designation (NOPB = lead-free plating). Both parts are pin-compatible and functionally interchangeable in circuit applications.

Q: What does the NOPB designation mean?

A: NOPB indicates "No Outer Lead Plating" or lead-free finish on the component leads. This designation signifies compliance with RoHS directives and is required for applications subject to lead-free manufacturing standards.

Q: Are there any thermal or performance differences between LM109H and LM109H/NOPB?

A: No. Both variants deliver identical thermal performance, quiescent current (5.2mA), and maximum supply current (10mA). Operating temperature range, protection features, and electrical characteristics are equivalent across both part numbers.

Q: What is the TO-39-3 package specification?

A: TO-39-3 is a three-lead metal can package in through-hole configuration. The supplier device package designation is TO-3. This package provides robust thermal characteristics suitable for linear regulator applications requiring heat dissipation in the -55°C to 150°C operating range.

Q: Can these parts be used in new designs or only as replacements?

A: Both LM109H and LM109H/NOPB are active products suitable for new designs. However, for modern applications, designers should evaluate current-generation voltage regulator alternatives, as these parts represent legacy linear regulator technology. The LM109H series remains appropriate for applications requiring fixed 5.05V output at 200mA with through-hole packaging.

Q: What inventory status should I expect?

A: The LM109H maintains 1302 pieces in stock, while LM109H/NOPB has 1328 pieces available. Both are classified as new original stock with active product status from Texas Instruments.