LM2687MM/NOPB Equivalent & Substitute Parts

Part Overview

The LM2687MM/NOPB is a charge pump switching regulator IC manufactured by Texas Instruments, designed to generate negative adjustable output voltages from 2.7V to 5.5V input supplies. This device delivers 10mA output current and operates at 110kHz switching frequency in an 8-TSSOP package. The product is currently obsolete, making identification of suitable substitute components essential for ongoing system support and new design implementations.

Substiute Parts

LM2687MM/NOPB

Texas InstrumentsIn Stock: 18232LM2687MM/NOPB Datasheet

Current PartRFQ

LM27761DSGR

Texas InstrumentsIn Stock: 65447LM27761DSGR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM2687MM/NOPB is determined by the following critical parameters:

• Output Configuration: Negative voltage generation capability
• Topology: Charge pump architecture
• Output Type: Adjustable voltage output
• Voltage Range: Input 2.7V–5.5V; Output -1.5V to -5.2V
• Output Current: Minimum 10mA capability
• Package Compatibility: Surface mount 8-pin configuration
• Compliance: ROHS3 compliance and MSL rating

The LM27761DSGR qualifies as a direct substitute based on these parameters. While it offers enhanced specifications (250mA output current, 2MHz switching frequency, and active product status), it maintains full compatibility with the electrical and mechanical requirements of the LM2687MM/NOPB.

Parameter Comparison

Engineering Selection Recommendations

The LM27761DSGR is the recommended substitute for the obsolete LM2687MM/NOPB. Both devices maintain identical input voltage ranges (2.7V–5.5V), output voltage adjustability (-1.5V to -5V/-5.2V), and operating temperature specifications (-40°C to 85°C). Both are ROHS3 compliant with MSL rating of 1, ensuring equivalent environmental and regulatory compliance.

The LM27761DSGR offers superior performance characteristics with 250mA output current capacity versus 10mA, and operates at 2MHz switching frequency compared to 110kHz. The active product status of the LM27761DSGR ensures long-term availability and supply chain continuity, addressing the obsolescence of the original component.

Frequently Asked Questions (FAQ)

Q: Can the LM27761DSGR directly replace the LM2687MM/NOPB in existing designs?

A: Yes. Both devices share identical input voltage ranges (2.7V–5.5V), adjustable negative output voltage capability (-1.5V to -5V/-5.2V range), and operating temperature specifications. The LM27761DSGR provides higher output current capacity (250mA versus 10mA), which is a superset capability that maintains backward compatibility.

Q: What are the package differences between these devices?

A: The LM2687MM/NOPB uses an 8-TSSOP/8-MSOP package (0.118", 3.00mm width). The LM27761DSGR uses an 8-WFDFN Exposed Pad package (8-WSON 2x2). Both are surface mount 8-pin configurations, though PCB layout modifications may be required due to different footprints.

Q: Are there compliance differences between the two parts?

A: No. Both devices are ROHS3 compliant with MSL rating of 1 (unlimited moisture sensitivity level). Both carry identical REACH and ECCN classifications (REACH Unaffected, EAR99).

Q: Why does the LM27761DSGR have higher switching frequency?

A: The LM27761DSGR operates at 2MHz versus 110kHz for the LM2687MM/NOPB. This higher frequency allows for smaller external component values and improved transient response, representing an enhancement in the substitute design.

Q: Is the LM27761DSGR suitable for applications requiring only 10mA output current?

A: Yes. The LM27761DSGR is rated for 250mA output current, which exceeds the 10mA requirement of the original LM2687MM/NOPB. Operating at lower than maximum rated current does not compromise device functionality or reliability.