LM2794BL LED Driver IC Equivalent & Substitute Parts

Part Overview

The LM2794BL is a 4-output LED driver IC with integrated DC-DC regulator utilizing switched capacitor (charge pump) topology for backlight applications. Manufactured by Texas Instruments, this component operates across a 2.7V to 5.5V supply range with 20mA per-channel output capability and supports both analog and PWM dimming control at 515kHz switching frequency.

The LM2794BL is classified as obsolete product status. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for legacy systems or new designs requiring compatible functionality.

Substiute Parts

LM2794BL

Texas InstrumentsIn Stock: 1870LM2794BL Datasheet

Current PartRFQ

LM2794TL/NOPB

Texas InstrumentsIn Stock: 3104LM2794TL/NOPB Datasheet

Parametric EquivalentRFQ

MAX1573ETE+T

Analog Devices Inc./Maxim IntegratedIn Stock: 5431MAX1573ETE+T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LM2794BL are identified based on strict parametric equivalence within the following criteria:

Primary Equivalence Parameters:

• Topology: Switched Capacitor (Charge Pump)
• Number of Outputs: 4
• Supply Voltage Range: 2.7V to 5.5V minimum compatibility
• Output Voltage: 3.8V or compatible regulation
• Dimming Control: PWM capability (core requirement)
• Application: Backlight LED driver
• Mounting Type: Surface Mount

Acceptable Variation Parameters:

• Current per Channel: Minimum 20mA (higher ratings acceptable for design margin)
• Switching Frequency: Variation acceptable if within typical LED driver operating range
• Package Type: Different BGA or QFN packages acceptable if pin-compatible or functionally equivalent
• Operating Temperature: Extended range acceptable

Two substitute parts meet these criteria with documented compatibility.

Parameter Comparison

Engineering Selection Recommendations

LM2794TL/NOPB (Parametric Equivalent - Preferred for Direct Replacement)

The LM2794TL/NOPB is the primary substitute for the obsolete LM2794BL. This part maintains identical electrical specifications, package configuration, and pinout. The LM2794TL/NOPB is currently in active production status with ROHS3 compliance certification. Inventory availability is documented at 3075 pieces. This part requires no design modification and provides direct functional equivalence for legacy system support or new designs requiring LM2794 series compatibility.

MAX1573ETE+T (Manufacturer-Recommended Alternative)

The MAX1573ETE+T is designated as the manufacturer-recommended substitute when design flexibility permits package and topology changes. This Analog Devices/Maxim Integrated component maintains the same 4-output switched capacitor topology and supply voltage range. Key differences include higher per-channel current capability (28mA versus 20mA), increased switching frequency (1MHz versus 515kHz), and different package format (16-TQFN versus 14-DSBGA). The MAX1573ETE+T is active production status with ROHS3 compliance. This option is suitable for new designs or redesigns where the enhanced current capability and higher switching frequency provide performance advantages. Package migration requires PCB layout modification.

Both substitutes are ROHS3 compliant and REACH unaffected, addressing regulatory requirements for the obsolete LM2794BL.

Frequently Asked Questions (FAQ)

Q: Can the LM2794TL/NOPB be used as a direct replacement for the LM2794BL without PCB modification?

A: Yes. The LM2794TL/NOPB maintains identical pinout, package configuration (14-DSBGA), electrical specifications, and functional characteristics. No PCB layout changes are required for substitution.

Q: What are the key differences between the LM2794TL/NOPB and MAX1573ETE+T?

A: The LM2794TL/NOPB is a parametric equivalent with identical specifications. The MAX1573ETE+T differs in three areas: package type (16-TQFN versus 14-DSBGA), per-channel current rating (28mA versus 20mA), and switching frequency (1MHz versus 515kHz). The MAX1573ETE+T requires PCB redesign but offers higher current capability.

Q: Is the LM2794TL/NOPB suitable for new designs?

A: Yes. The LM2794TL/NOPB is active production status with current inventory availability. It is appropriate for both legacy system support and new designs requiring 4-output LED driver functionality with switched capacitor topology.

Q: What is the impact of the different package types between LM2794BL and MAX1573ETE+T?

A: The LM2794BL uses 14-DSBGA package; the MAX1573ETE+T uses 16-TQFN (4x4) package. These are not pin-compatible. Substitution requires PCB layout redesign, schematic review, and thermal management evaluation due to different package footprints and thermal characteristics.

Q: Are both substitute parts RoHS compliant?

A: Yes. Both the LM2794TL/NOPB and MAX1573ETE+T are ROHS3 compliant. The original LM2794BL is RoHS non-compliant. Substitution addresses regulatory compliance requirements for new production.

Q: Can the MAX1573ETE+T be used in applications requiring analog dimming control?

A: The MAX1573ETE+T supports PWM dimming only. It does not support analog dimming control. If analog dimming is a design requirement, the LM2794TL/NOPB is the appropriate substitute, as it maintains both analog and PWM dimming capability.

Q: What is the operating temperature range difference between substitutes?

A: The LM2794BL and LM2794TL/NOPB operate from -30°C to 85°C. The MAX1573ETE+T operates from -40°C to 85°C, providing extended low-temperature performance. This difference is not significant for most backlight applications.