LP8543SQE LED Driver IC Equivalent & Substitute Parts

Part Overview

The LP8543SQE is a Texas Instruments LED Driver IC designed for backlight applications, featuring a 7-output DC-DC regulator with step-up (boost) topology and PWM dimming capability. This part is classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement continuity. The LP8543SQE delivers 60mA per channel output with a 40V output voltage and operates across a 5.5V to 22V supply range, making it suitable for multi-LED backlight driver applications in consumer and industrial equipment.

Substiute Parts

LP8543SQE

Texas InstrumentsIn Stock: 843LP8543SQE Datasheet

Current PartRFQ

LP8543SQ/NOPB

Texas InstrumentsIn Stock: 1096LP8543SQ/NOPB Datasheet

DirectRFQ

LP8543SQE/NOPB

Texas InstrumentsIn Stock: 800LP8543SQE/NOPB Datasheet

Parametric EquivalentRFQ

LP8543SQX/NOPB

Texas InstrumentsIn Stock: 1002LP8543SQX/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LP8543SQE are determined by strict equivalence across the following critical parameters: manufacturer (Texas Instruments), base product number (LP8543), package type (24-WFQFN), and all electrical specifications including supply voltage range (5.5V–22V), output voltage (40V), per-channel current (60mA), switching frequency (625kHz–1.25MHz), and PWM dimming capability. All substitute parts maintain identical functional performance and pinout compatibility. Substitution is valid only when these parameters remain unchanged across the part variants.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts (LP8543SQ/NOPB, LP8543SQE/NOPB, LP8543SQX/NOPB) are functionally equivalent to the LP8543SQE and maintain identical electrical and mechanical specifications. The primary differentiators are product status and compliance certifications.

LP8543SQ/NOPB is the preferred substitute for new designs requiring the widest operating temperature range (-40°C to 85°C) and active product status from Texas Instruments. This part carries ROHS3 compliance and MSL 1 rating, indicating superior moisture handling characteristics suitable for long-term storage and automated assembly processes.

LP8543SQE/NOPB and LP8543SQX/NOPB are direct parametric equivalents with identical operating temperature range (-30°C to 85°C) as the original LP8543SQE. Both carry ROHS3 compliance and MSL 1 ratings. Selection between these two variants depends on availability and procurement lead times, as electrical performance and package specifications are identical.

For applications where the original LP8543SQE operating temperature range is sufficient, any of the three active substitutes are suitable. For applications requiring extended low-temperature operation below -30°C, LP8543SQ/NOPB is the only option among the substitutes.

Frequently Asked Questions (FAQ)

Q: Can LP8543SQ/NOPB replace LP8543SQE in existing designs?

A: Yes. LP8543SQ/NOPB is a direct substitute with identical electrical specifications, package type (24-WFQFN), and pinout. The primary advantage is active product status and extended operating temperature range (-40°C to 85°C versus -30°C to 85°C). No design changes are required.

Q: What is the difference between LP8543SQE/NOPB and LP8543SQX/NOPB?

A: Both parts are parametric equivalents with identical electrical specifications, operating temperature range, and package type. The difference is in the suffix designation only. Selection should be based on availability and procurement requirements.

Q: Why is RoHS compliance important for this substitution?

A: The original LP8543SQE is RoHS non-compliant, while all active substitutes (LP8543SQ/NOPB, LP8543SQE/NOPB, LP8543SQX/NOPB) are ROHS3 compliant. For new designs or applications subject to RoHS regulations, the compliant substitutes are required.

Q: Does the Moisture Sensitivity Level (MSL) affect substitution?

A: The original LP8543SQE has MSL 3 (168 hours), while all substitutes have MSL 1 (unlimited). MSL 1 indicates superior moisture resistance and longer shelf life. This is an improvement over the original part and does not restrict substitution.

Q: Are the packaging formats (bulk versus Tape & Reel) compatible?

A: Yes. The LP8543SQE is supplied in bulk packaging, while substitutes are supplied in Tape & Reel (TR) format. Both formats contain identical die and package specifications. Tape & Reel is standard for automated assembly processes and does not affect electrical or mechanical compatibility.

Q: Which substitute should I choose for new production designs?

A: LP8543SQ/NOPB is recommended for new designs due to active product status, extended operating temperature range, and superior compliance certifications. If the narrower temperature range (-30°C to 85°C) is acceptable, LP8543SQE/NOPB or LP8543SQX/NOPB are equivalent alternatives based on availability.