LP2951ACD Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The LP2951ACD is a linear voltage regulator IC from onsemi, classified as a Power Management (PMIC) component. This device functions as a positive adjustable (fixed) output regulator capable of delivering 100mA output current in an 8-SOIC surface mount package. The LP2951ACD is currently marked as obsolete, making identification of functionally equivalent substitute parts essential for ongoing design support, production continuity, and component sourcing.

Key Parameters

Parameter	Value
Manufacturer Part Number	LP2951ACD
Manufacturer	onsemi
Category	Power Management (PMIC)
Description	IC REG LIN POS ADJ 100MA 8SOIC
Product Status	Obsolete
Output Configuration	Positive
Output Type	Adjustable (Fixed)
Number of Regulators	1
Voltage - Input (Max)	30V
Voltage - Output (Min/Fixed)	1.235V (5V)
Voltage - Output (Max)	30V
Voltage Dropout (Max)	0.45V @ 100mA
Current - Output	100mA
Current - Quiescent (Iq)	120 µA
Current - Supply (Max)	12 mA
Protection Features	Over Current, Over Temperature
Operating Temperature	-40°C ~ 125°C
Mounting Type	Surface Mount
Package / Case	8-SOIC (0.154", 3.90mm Width)
RoHS Status	RoHS non-compliant
Moisture Sensitivity Level (MSL)	1 (Unlimited)

Substitute Part Grouping Explanation

Substitute parts for the LP2951ACD are identified based on strict alignment with the following critical parameters:

Core Substitution Criteria:

Output Configuration: Positive
Output Type: Adjustable (Fixed)
Number of Regulators: 1
Voltage - Input (Max): 30V
Current - Output: 100mA
Mounting Type: Surface Mount
Package / Case: 8-SOIC (0.154", 3.90mm Width)
Operating Temperature Range: -40°C ~ 125°C

Substitute parts must maintain compatibility across these electrical and mechanical specifications. Variations in quiescent current, dropout voltage, and control features are permissible provided the core functional parameters remain within acceptable tolerances for the application.

Parameter Comparison

Parameter	LP2951ACD (Main)	LP2951-02YM	LP2951-02YM-TR	LP2951-50QDRQ1	LP2951CS-L-3-3/TR	LP2951CS-L-5-0/TR
Manufacturer	onsemi	Microchip Technology	Microchip Technology	Texas Instruments	MaxLinear, Inc.	MaxLinear, Inc.
Product Status	Obsolete	Active	Active	Active	Active	Active
Output Configuration	Positive	Positive	Positive	Positive	Positive	Positive
Output Type	Adjustable (Fixed)	Adjustable (Fixed)	Adjustable (Fixed)	Adjustable (Fixed)	Fixed	Adjustable (Fixed)
Number of Regulators	1	1	1	1	1	1
Voltage - Input (Max)	30V	30V	30V	30V	30V	30V
Voltage - Output (Min/Fixed)	1.235V (5V)	1.24V (5V)	1.24V (5V)	1.235V (5V)	3.3V	1.235V (5V)
Voltage - Output (Max)	30V	29V	29V	30V	—	29V
Voltage Dropout (Max)	0.45V @ 100mA	0.6V @ 100mA	0.6V @ 100mA	0.6V @ 100mA	0.45V @ 100mA	0.45V @ 100mA
Current - Output	100mA	100mA	100mA	100mA	100mA	100mA
Current - Quiescent (Iq)	120 µA	150 µA	150 µA	120 µA	170 µA	170 µA
Current - Supply (Max)	12 mA	14 mA	14 mA	14 mA	12 mA	12 mA
Protection Features	Over Current, Over Temperature	—	—	Over Current, Over Temperature, Short Circuit	Over Current, Over Temperature	Over Current, Over Temperature
Operating Temperature	-40°C ~ 125°C	-40°C ~ 125°C	-40°C ~ 125°C	-40°C ~ 125°C (TJ)	-40°C ~ 125°C	-40°C ~ 125°C
Mounting Type	Surface Mount	Surface Mount	Surface Mount	Surface Mount	Surface Mount	Surface Mount
Package / Case	8-SOIC	8-SOIC	8-SOIC	8-SOIC	8-SOIC	8-SOIC
RoHS Status	RoHS non-compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	RoHS Compliant	RoHS Compliant
Moisture Sensitivity Level (MSL)	1 (Unlimited)	1 (Unlimited)	1 (Unlimited)	3 (168 Hours)	1 (Unlimited)	1 (Unlimited)

Engineering Selection Recommendations

Primary Substitutes (Active Status, Full Compatibility):

LP2951-02YM and LP2951-02YM-TR from Microchip Technology are direct functional equivalents with active product status. Both maintain the adjustable (fixed) output configuration, 100mA output current, and 8-SOIC package. These parts achieve ROHS3 compliance and offer unlimited moisture sensitivity rating. The primary trade-off is increased quiescent current (150 µA vs. 120 µA) and maximum supply current (14 mA vs. 12 mA), with slightly higher dropout voltage (0.6V vs. 0.45V @ 100mA).

LP2951CS-L-5-0/TR from MaxLinear, Inc. provides equivalent electrical performance with active product status and RoHS compliance. This part maintains the 0.45V dropout voltage specification and 12 mA maximum supply current, matching the LP2951ACD more closely than Microchip alternatives. The quiescent current is higher at 170 µA.

Specialized Substitute (Automotive Grade):

LP2951-50QDRQ1 from Texas Instruments is qualified to AEC-Q100 automotive standards with active product status. This part includes enhanced protection features (Over Current, Over Temperature, Short Circuit) and maintains the 120 µA quiescent current specification. The MSL rating of 3 (168 Hours) requires controlled storage conditions. This option is suitable for automotive or high-reliability applications.

Fixed Output Alternative:

LP2951CS-L-3-3/TR from MaxLinear, Inc. is a fixed 3.3V output variant. This part is applicable only when a fixed 3.3V output is required and the application does not depend on adjustable output voltage capability.

Compliance Consideration:

The LP2951ACD is RoHS non-compliant. All active substitute parts listed above achieve RoHS compliance (ROHS3 or RoHS Compliant), making them suitable for applications requiring regulatory compliance with modern environmental standards.

Frequently Asked Questions (FAQ)

Q: Can LP2951-02YM directly replace LP2951ACD in existing designs?

A: LP2951-02YM is functionally compatible as a direct replacement. Both parts share identical output configuration (positive adjustable/fixed), output current (100mA), input voltage rating (30V max), operating temperature range (-40°C ~ 125°C), and 8-SOIC package. The primary differences are increased quiescent current (150 µA vs. 120 µA), higher dropout voltage (0.6V vs. 0.45V @ 100mA), and active product status with RoHS compliance. Verify that the application can tolerate these parameter variations before implementation.

Q: What is the difference between LP2951-02YM and LP2951-02YM-TR?

A: Both parts are identical in electrical specifications and come from Microchip Technology. The difference is packaging format: LP2951-02YM is supplied in Tube packaging, while LP2951-02YM-TR is supplied in Cut Tape (CT) & Digi-Reel format. Select based on procurement and assembly requirements.

Q: Why does LP2951-50QDRQ1 have a higher MSL rating?

A: LP2951-50QDRQ1 carries MSL 3 (168 Hours) due to its automotive-grade qualification (AEC-Q100). This classification requires controlled moisture exposure during storage and handling. Standard industrial parts like LP2951-02YM carry MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. Automotive-grade parts undergo additional qualification testing that may result in different moisture sensitivity classifications.

Q: Is LP2951CS-L-3-3/TR a suitable substitute for adjustable output applications?

A: No. LP2951CS-L-3-3/TR is a fixed 3.3V output regulator, while LP2951ACD supports adjustable (fixed) output voltage. This part is only applicable when a fixed 3.3V output is the design requirement. For applications requiring adjustable output voltage capability, use LP2951-02YM, LP2951-02YM-TR, LP2951-50QDRQ1, or LP2951CS-L-5-0/TR.

Q: What are the key parameters that determine substitutability?

A: Substitutability is determined by: (1) Output Configuration (Positive), (2) Output Type (Adjustable or Fixed), (3) Number of Regulators (1), (4) Maximum Input Voltage (30V), (5) Output Current (100mA), (6) Mounting Type (Surface Mount), (7) Package Type (8-SOIC), and (8) Operating Temperature Range (-40°C ~ 125°C). All substitute parts must match these core specifications. Secondary parameters such as quiescent current, dropout voltage, and protection features may vary within acceptable application tolerances.

Q: Are all substitute parts RoHS compliant?

A: All active substitute parts listed (LP2951-02YM, LP2951-02YM-TR, LP2951-50QDRQ1, LP2951CS-L-3-3/TR, LP2951CS-L-5-0/TR) achieve RoHS compliance. The original LP2951ACD is RoHS non-compliant. If RoHS compliance is a design requirement, any of the active substitutes will satisfy this requirement.

Q: Can I use LP2951-50QDRQ1 in non-automotive applications?

A: Yes. LP2951-50QDRQ1 is qualified to automotive standards but is not restricted to automotive use. This part can be used in any application where the electrical specifications are compatible. The automotive qualification provides additional assurance of reliability and performance consistency, making it suitable for high-reliability industrial or consumer applications as well.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message