LP8543SQ LED Driver IC Equivalent & Substitute Parts

Part Overview

The LP8543SQ is a 7-output LED driver IC with integrated DC-DC step-up (boost) regulator designed for backlight applications. This device operates from a 5.5V to 22V supply and delivers up to 40V output with 60mA per channel capability using PWM dimming control. The LP8543SQ is classified as obsolete, making identification of compatible substitute parts essential for ongoing production support and design continuity.

Substiute Parts

LP8543SQ

Texas InstrumentsIn Stock: 1910LP8543SQ Datasheet

Current PartRFQ

LP8543SQ/NOPB

Texas InstrumentsIn Stock: 1096LP8543SQ/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LP8543SQ is determined by strict equivalence across the following critical parameters:

• Topology: Step-Up (Boost) DC-DC regulator
• Number of Outputs: 7 channels
• Voltage Supply Range: 5.5V to 22V input
• Output Voltage: 40V
• Current Rating: 60mA per channel
• Dimming Control: PWM
• Package: 24-WQFN (4x4) with exposed pad
• Mounting: Surface mount
• Operating Temperature Range: -40°C to 85°C

The LP8543SQ/NOPB qualifies as a direct substitute based on identical electrical specifications and package configuration. The primary distinction is packaging format (Tape & Reel versus bulk) and product status (Active versus Obsolete).

Parameter Comparison

Engineering Selection Recommendations

The LP8543SQ/NOPB is the direct functional equivalent of the LP8543SQ. Both devices share identical electrical characteristics, pin configuration, and package geometry. Selection between these parts should be based on the following factors:

Product Status: The LP8543SQ is classified as obsolete, while LP8543SQ/NOPB maintains active status with Texas Instruments. For new designs or ongoing production requiring long-term availability, LP8543SQ/NOPB is the appropriate choice.

Compliance: LP8543SQ/NOPB carries ROHS3 compliance certification, whereas the LP8543SQ is RoHS non-compliant. Applications subject to RoHS regulatory requirements must use LP8543SQ/NOPB.

Packaging: LP8543SQ/NOPB is supplied in Tape & Reel format, suitable for automated assembly processes. The original LP8543SQ may be available in bulk packaging. Packaging selection depends on manufacturing volume and assembly equipment compatibility.

Frequently Asked Questions (FAQ)

Q: Can LP8543SQ/NOPB be used as a direct replacement for LP8543SQ in existing designs?

A: Yes. Both devices are electrically and mechanically identical. Pin configuration, package footprint, and electrical performance are equivalent. No circuit modifications are required.

Q: What is the difference between LP8543SQ and LP8543SQ/NOPB?

A: The primary differences are product status (Obsolete versus Active), packaging format (Bulk versus Tape & Reel), and RoHS compliance (non-compliant versus ROHS3 compliant). Electrical specifications and package geometry are identical.

Q: Is the 24-WQFN package footprint identical between both parts?

A: Yes. Both LP8543SQ and LP8543SQ/NOPB use the 24-WQFN (4x4) package with exposed pad. PCB layout and assembly processes are interchangeable.

Q: Which part should be specified for new production designs?

A: LP8543SQ/NOPB is recommended for new designs due to active product status and ROHS3 compliance certification. This ensures long-term availability and regulatory compliance.

Q: Are there any thermal or performance differences between these parts?

A: No. Operating temperature range, switching frequency, output current capability, and thermal characteristics are identical across both devices.

Q: What is the significance of the "/NOPB" suffix?

A: The "/NOPB" designation indicates the part is supplied in Tape & Reel packaging without lead (Pb-free), consistent with RoHS3 requirements.