LM2940CSX-9.0 Equivalent & Substitute Parts

Part Overview

The LM2940CSX-9.0 is a linear voltage regulator IC designed for positive fixed 9V output at 1A maximum current in a TO-263 (DDPAK-3) surface mount package. This device provides low dropout regulation with integrated protection features including over-current, over-temperature, reverse polarity, and short-circuit protection. The main part number is currently classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement.

Substiute Parts

LM2940CSX-9.0

Texas InstrumentsIn Stock: 4043LM2940CSX-9.0 Datasheet

Current PartRFQ

LM2940CSX-9.0/NOPB

National SemiconductorIn Stock: 2252LM2940CSX-9.0/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM2940CSX-9.0 is determined by strict equivalence across the following critical parameters:

• Fixed output voltage of 9V
• Maximum output current of 1A
• Maximum input voltage of 26V
• Dropout voltage specification of 0.8V @ 1A
• Quiescent current of 10 mA
• PSRR of 64dB (120Hz)
• TO-263 (DDPAK-3) package configuration
• Operating temperature range of 0°C to 125°C
• Identical protection feature set

The LM2940CSX-9.0/NOPB meets all these criteria and qualifies as a direct substitute. This part maintains full electrical and mechanical compatibility with the original specification.

Parameter Comparison

Engineering Selection Recommendations

The LM2940CSX-9.0/NOPB is the appropriate substitute for the obsolete LM2940CSX-9.0. Both parts share identical electrical specifications and package configuration. The primary distinction is product status: the original part is obsolete while the substitute maintains active production status, ensuring long-term availability and supply chain continuity.

Both parts carry EAR99 export classification and are subject to identical tariff codes. The substitute part is suitable for direct replacement in existing designs without circuit modification or re-qualification when component availability becomes a constraint.

Frequently Asked Questions (FAQ)

Q: Can the LM2940CSX-9.0/NOPB be used as a direct replacement for the LM2940CSX-9.0?

A: Yes. Both parts are electrically and mechanically identical across all specified parameters including output voltage, current rating, dropout voltage, quiescent current, PSRR, package type, and protection features. Direct substitution is supported without design changes.

Q: What does the "/NOPB" suffix indicate?

A: The "/NOPB" suffix designates a part manufactured without lead-based solder (lead-free plating). This marking indicates compliance with lead-free manufacturing processes while maintaining identical electrical performance.

Q: Why is the original LM2940CSX-9.0 listed as obsolete?

A: Product obsolescence reflects end-of-life status from the original manufacturer. The substitute part LM2940CSX-9.0/NOPB remains in active production, providing continued availability for applications requiring this 9V, 1A linear regulator specification.

Q: Are there any package compatibility concerns?

A: No. Both parts use the TO-263 (DDPAK-3) surface mount package with identical pinout and thermal characteristics. PCB layouts and thermal management designs require no modification.

Q: What compliance certifications apply to both parts?

A: Both parts carry EAR99 export classification and are assigned HTSUS code 8542.39.0001. The substitute part maintains equivalent regulatory and trade compliance status.