LP3891ESX-1.2 Equivalent & Substitute Parts

Part Overview

The LP3891ESX-1.2 is a linear voltage regulator IC from Texas Instruments, classified as a Power Management (PMIC) component. It delivers a fixed positive output of 1.2V at 800mA with a maximum dropout voltage of 0.4V. The device integrates protection features including over-current, over-temperature, short-circuit, and under-voltage lockout (UVLO) protection, operating across the temperature range of -40°C to 125°C in a TO-263 (DDPAK-5) surface-mount package.

The original LP3891ESX-1.2 carries an obsolete product status. Identifying equivalent and substitute parts is necessary to ensure design continuity, maintain supply chain reliability, and access components with active manufacturing status and improved compliance certifications.

Substiute Parts

LP3891ESX-1.2

Texas InstrumentsIn Stock: 1926LP3891ESX-1.2 Datasheet

Current PartRFQ

LP3891ESX-1.2/NOPB

Texas InstrumentsIn Stock: 2850LP3891ESX-1.2/NOPB Datasheet

DirectRFQ

LP3881ESX-1.2/NOPB

National SemiconductorIn Stock: 1502LP3881ESX-1.2/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LP3891ESX-1.2 are classified based on strict electrical and mechanical parameter alignment:

Direct Manufacturer Equivalent: Parts maintaining identical electrical specifications, output configuration, and package type while differing only in product status or packaging format.

Parametric Equivalent: Parts meeting all critical electrical parameters (output voltage, output current, input voltage range, dropout voltage, protection features, and operating temperature) and sharing the same mechanical package, with potential variations in secondary characteristics such as quiescent current or PSRR performance within acceptable tolerances.

The following key parameters determine substitution eligibility:

• Fixed output voltage of 1.2V
• Output current capability of 800mA
• Maximum input voltage of 5.5V
• TO-263 (DDPAK-5) package configuration
• Operating temperature range of -40°C to 125°C
• Presence of Enable control feature and core protection mechanisms

Parameter Comparison

Engineering Selection Recommendations

LP3891ESX-1.2/NOPB is the primary direct equivalent for obsolete LP3891ESX-1.2 designs. Both parts are manufactured by Texas Instruments with identical electrical specifications and TO-263 package configuration. The LP3891ESX-1.2/NOPB carries active product status and ROHS3 compliance, making it suitable for new designs and production environments requiring regulatory adherence. The difference in packaging format (Tape & Reel versus Bulk) affects procurement and assembly processes but does not impact electrical performance or pin compatibility.

LP3881ESX-1.2/NOPB from National Semiconductor serves as a parametric equivalent with superior dropout voltage performance (0.16V versus 0.4V at 800mA). This characteristic provides improved efficiency in applications with tight input-to-output voltage margins. All critical electrical parameters, protection features, and mechanical package specifications align with the original LP3891ESX-1.2. Selection of this alternative depends on design requirements for reduced power dissipation and thermal management considerations.

Both substitute parts maintain identical output voltage, output current, input voltage range, quiescent current, PSRR characteristics, and operating temperature specifications. Package pinout and mechanical dimensions remain consistent across all three parts within the TO-263 (DDPAK-5) standard.

Frequently Asked Questions (FAQ)

Q: Can LP3891ESX-1.2/NOPB be used as a direct replacement for LP3891ESX-1.2?

A: Yes. Both parts share identical electrical specifications, output voltage (1.2V), output current (800mA), dropout voltage (0.4V @ 800mA), and TO-263 package configuration. The primary difference is product status (Active versus Obsolete) and RoHS compliance (ROHS3 Compliant versus Non-compliant). Pin compatibility and functional performance are equivalent.

Q: What is the advantage of LP3881ESX-1.2/NOPB over LP3891ESX-1.2/NOPB?

A: The LP3881ESX-1.2/NOPB features a lower maximum dropout voltage of 0.16V at 800mA compared to 0.4V for the LP3891ESX-1.2/NOPB. This reduced dropout voltage results in lower power dissipation and improved thermal performance in applications where input-to-output voltage differential is limited.

Q: Are all three parts pin-compatible?

A: Yes. All three parts use the TO-263 (DDPAK-5) package with identical pinout and mechanical dimensions. Direct PCB layout compatibility is maintained without requiring design modifications.

Q: Does packaging format (Tape & Reel versus Bulk) affect electrical performance?

A: No. Packaging format affects procurement, storage, and assembly processes only. Electrical specifications, performance characteristics, and reliability remain unchanged regardless of packaging format.

Q: Which substitute part should be selected for new designs?

A: LP3891ESX-1.2/NOPB is recommended for new designs due to active product status and ROHS3 compliance certification. LP3881ESX-1.2/NOPB is an alternative when superior dropout voltage performance is required for efficiency optimization.

Q: Are protection features identical across all three parts?

A: Yes. All three parts include over-current, over-temperature, short-circuit, and under-voltage lockout (UVLO) protection features with Enable control capability. Protection thresholds and response characteristics are equivalent.