LM2940T-8.0 Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The LM2940T-8.0 is a linear voltage regulator IC from Texas Instruments designed for positive fixed output applications. This device delivers 1A output current at a fixed 8V output with a maximum input voltage of 26V and dropout voltage of 1V at full load. The part is classified as Last Time Buy, indicating end-of-life status. Identifying equivalent and substitute parts is necessary to ensure design continuity and maintain supply chain reliability for applications currently utilizing this regulator.

Key Parameters

Parameter	Value
Manufacturer	Texas Instruments
Part Number	LM2940T-8.0
Category	Power Management (PMIC)
Package / Case	TO-220-3
Output Configuration	Positive
Output Type	Fixed
Voltage - Output (Min/Fixed)	8V
Voltage - Input (Max)	26V
Current - Output	1A
Voltage Dropout (Max)	1V @ 1A
Operating Temperature	-40°C ~ 125°C
Mounting Type	Through Hole
RoHS Status	ROHS3 Compliant
Product Status	Last Time Buy

Substitute Part Grouping Explanation

Substitute parts for the LM2940T-8.0 are identified based on the following critical parameters that determine functional equivalence:

Primary Substitution Criteria:

Output voltage: 8V fixed
Output configuration: Positive
Package type: TO-220-3 (mechanical and thermal compatibility)
Mounting type: Through Hole
Output current capability: minimum 1A
Maximum input voltage: 26V or greater
Operating temperature range: must encompass or match -40°C ~ 125°C

Substitution Categories:

Direct Equivalent (Identical Specifications): Parts with matching electrical specifications and identical product status or active status. These provide pin-for-pin replacement capability.

Functional Equivalent (Enhanced Specifications): Parts with superior or equal electrical performance characteristics, such as higher output current, lower dropout voltage, or broader operating temperature range. These maintain full functional compatibility while potentially offering improved performance margins.

Parameter Comparison

Parameter	LM2940T-8.0	LM2940T-8.0/NOPB	UA7808CKCS
Manufacturer	Texas Instruments	Texas Instruments	Texas Instruments
Product Status	Last Time Buy	Active	Obsolete
Package / Case	TO-220-3	TO-220-3	TO-220-3
Output Configuration	Positive	Positive	Positive
Output Type	Fixed	Fixed	Fixed
Voltage - Output (Min/Fixed)	8V	8V	8V
Voltage - Input (Max)	26V	26V	25V
Current - Output	1A	1A	1.5A
Voltage Dropout (Max)	1V @ 1A	1V @ 1A	2V @ 1A
Operating Temperature	-40°C ~ 125°C	-40°C ~ 125°C	0°C ~ 125°C
Mounting Type	Through Hole	Through Hole	Through Hole
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant

Engineering Selection Recommendations

LM2940T-8.0/NOPB is the primary recommended substitute. This part is a direct electrical equivalent with identical specifications and is currently in Active product status, ensuring long-term availability and supply chain stability. The NOPB designation indicates lead-free plating, maintaining RoHS3 compliance. This part is suitable for all applications currently using the LM2940T-8.0 without design modifications.

UA7808CKCS is a functional equivalent with enhanced output current capability (1.5A versus 1A) and is available in inventory. However, this part carries Obsolete product status, which may limit future availability. Additionally, the operating temperature range is restricted to 0°C ~ 125°C (versus -40°C ~ 125°C), making it unsuitable for applications requiring extended low-temperature operation. The maximum input voltage is 25V (versus 26V) and dropout voltage is higher at 2V @ 1A. Selection of this part should be limited to applications where the enhanced current capability is beneficial and temperature/voltage specifications are compatible.

Frequently Asked Questions (FAQ)

Q: Can LM2940T-8.0/NOPB be used as a direct replacement for LM2940T-8.0?

A: Yes. The LM2940T-8.0/NOPB is a direct pin-for-pin and functional equivalent. Both parts share identical electrical specifications, output voltage, current rating, dropout voltage, and operating temperature range. The primary difference is product status (Active versus Last Time Buy) and lead-free plating designation (NOPB).

Q: What are the key differences between LM2940T-8.0 and UA7808CKCS?

A: While both are 8V fixed output regulators in TO-220-3 packages, the UA7808CKCS has higher output current (1.5A versus 1A), higher dropout voltage (2V @ 1A versus 1V @ 1A), lower maximum input voltage (25V versus 26V), and a narrower operating temperature range (0°C ~ 125°C versus -40°C ~ 125°C). The UA7808CKCS is also Obsolete, whereas the LM2940T-8.0 is Last Time Buy.

Q: Is the TO-220-3 package compatible across all three parts?

A: Yes. All three parts use the TO-220-3 package with identical mechanical dimensions and pin configuration, enabling direct socket compatibility without PCB modifications.

Q: Can UA7808CKCS be used in applications requiring -40°C operation?

A: No. The UA7808CKCS operating temperature range is 0°C ~ 125°C, which does not include -40°C. Applications requiring extended low-temperature operation must use LM2940T-8.0 or LM2940T-8.0/NOPB.

Q: What is the significance of the NOPB designation on LM2940T-8.0/NOPB?

A: NOPB indicates "No Plumbum" (lead-free) plating. This designation confirms RoHS3 compliance and is standard for current production parts. The electrical and functional performance is identical to the original LM2940T-8.0.

Q: Which substitute part should be selected for new designs?

A: LM2940T-8.0/NOPB is the recommended choice for new designs. It maintains all specifications of the original part while offering Active product status and confirmed long-term availability.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message