LM27951SD LED Driver IC Equivalent & Substitute Parts

Part Overview

The LM27951SD is a 4-output LED driver IC with integrated DC-DC regulator using switched capacitor (charge pump) topology for backlight applications. This part is classified as "Not For New Designs" by Texas Instruments, making equivalent and substitute parts necessary for ongoing production and maintenance applications. The LM27951SD operates across a 2.8V to 5.5V supply range with PWM dimming capability and 30mA per-channel output current in a 14-WSON (4x3) surface mount package.

Substiute Parts

LM27951SD

Texas InstrumentsIn Stock: 1910LM27951SD Datasheet

Current PartRFQ

LM27951SD/NOPB

Texas InstrumentsIn Stock: 6268LM27951SD/NOPB Datasheet

DirectRFQ

LM27951SDX/NOPB

Texas InstrumentsIn Stock: 3296LM27951SDX/NOPB Datasheet

Parametric EquivalentRFQ

LM27952SD/NOPB

National SemiconductorIn Stock: 8348LM27952SD/NOPB Datasheet

Parametric EquivalentRFQ

LM27952SDX/NOPB

Texas InstrumentsIn Stock: 1511LM27952SDX/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM27951SD is determined by the following critical parameters:

• Topology: Switched Capacitor (Charge Pump) topology must be maintained
• Number of Outputs: 4-output configuration required
• Voltage Supply Range: Minimum 2.8V to maximum 5.5V (or compatible subset)
• Output Voltage Range: 2.5V ~ 3.9V
• Current per Channel: 30mA
• Switching Frequency: 750kHz
• PWM Dimming: Required
• Package: 14-WSON (4x3) / 14-WFDFN Exposed Pad
• Mounting Type: Surface Mount

The substitute parts are grouped into two categories:

Direct Manufacturer Equivalents (LM27951 series with /NOPB suffix): Identical electrical and mechanical specifications with improved compliance status.

Parametric Equivalents (LM27952 series): Functionally equivalent with minor supply voltage minimum variation (3V vs 2.8V minimum), maintaining all other critical parameters.

Parameter Comparison

Engineering Selection Recommendations

LM27951SD/NOPB is the primary direct equivalent. It maintains identical electrical specifications while offering Active product status and ROHS3 compliance, addressing the obsolescence concern of the original LM27951SD.

LM27951SDX/NOPB provides parametric equivalence with identical supply voltage range (2.8V minimum) and Active status with ROHS3 compliance. The "X" suffix indicates extended temperature or processing variation; electrical performance remains equivalent.

LM27952SD/NOPB and LM27952SDX/NOPB are parametric equivalents with a 3V minimum supply voltage (versus 2.8V for LM27951 variants). These are suitable for applications where the minimum supply voltage does not fall below 3V. Both maintain Active product status and all other critical electrical parameters.

For applications requiring the full 2.8V minimum supply voltage capability, LM27951SD/NOPB or LM27951SDX/NOPB are the appropriate selections. For applications with 3V or higher minimum supply voltage, LM27952 variants offer additional inventory availability.

Frequently Asked Questions (FAQ)

Q: Can LM27952 variants substitute for LM27951 in all applications?

A: LM27952 variants have a 3V minimum supply voltage versus 2.8V for LM27951 variants. Substitution is valid only if your application's minimum supply voltage is 3V or higher. If your circuit operates below 3V, use LM27951 variants exclusively.

Q: What is the difference between LM27951SD and LM27951SD/NOPB?

A: Both are electrically identical. The /NOPB suffix indicates "No Plumbum" (lead-free) processing and ROHS3 compliance. LM27951SD/NOPB is the recommended choice for new production due to Active product status and regulatory compliance.

Q: What does the "X" suffix in LM27951SDX/NOPB indicate?

A: The "X" suffix denotes a processing or temperature grade variation. Electrical specifications remain equivalent to LM27951SD/NOPB. Both are suitable for the same applications.

Q: Are all substitute parts available in the same 14-WSON (4x3) package?

A: Yes. All listed substitute parts use the 14-WFDFN Exposed Pad package with 14-WSON (4x3) supplier device package designation, ensuring mechanical and thermal compatibility.

Q: Which substitute part should I select for new designs?

A: The LM27951SD is marked "Not For New Designs." For new designs, select LM27951SD/NOPB or LM27951SDX/NOPB, both with Active status and ROHS3 compliance. These maintain the full 2.8V to 5.5V supply range and all original specifications.

Q: Are there any compliance differences between the substitute parts?

A: LM27951SD/NOPB and LM27951SDX/NOPB are ROHS3 compliant with REACH Unaffected status. LM27952SD/NOPB compliance information is not fully specified in available data. For applications with strict compliance requirements, LM27951 variants are the preferred choice.