LP3988IMF-3.0 Linear Voltage Regulator - Equivalent & Substitute Parts

Part Overview

The LP3988IMF-3.0 is a micropower linear voltage regulator IC from Texas Instruments, designed to deliver a fixed 3V output at up to 150mA. This device features integrated enable and power good control functions, along with over-temperature and short-circuit protection. The part is classified as obsolete, making identification of suitable equivalent and substitute components essential for ongoing design support and production continuity. Equivalent parts maintain identical electrical and mechanical specifications, while substitute parts offer compatible functionality within the allowed parameter ranges for this power management category.

Key Parameters

Parameter	Value
Manufacturer Part Number	LP3988IMF-3.0
Manufacturer	Texas Instruments
Category	Power Management (PMIC)
Output Configuration	Positive
Output Type	Fixed
Voltage - Output (Min/Fixed)	3V
Voltage - Input (Max)	6V
Current - Output	150mA
Voltage Dropout (Max)	0.15V @ 150mA
Current - Quiescent (Iq)	120 µA
Package / Case	SC-74A, SOT-753
Supplier Device Package	SOT-23-5
Operating Temperature	-40°C ~ 125°C
Product Status	Obsolete

Substitute Part Grouping Explanation

Substitution for the LP3988IMF-3.0 is determined by strict alignment of the following critical parameters:

Fixed output voltage of 3V
Maximum output current of 150mA
Positive output configuration
Maximum input voltage of 6V
SOT-23-5 package compatibility
Operating temperature range of -40°C to 125°C
Surface mount mounting type

The identified substitute parts maintain these core electrical and mechanical specifications. Variations in secondary parameters such as quiescent current, dropout voltage, PSRR characteristics, and specific control features are documented to enable informed selection based on application requirements.

Parameter Comparison

Parameter	LP3988IMF-3.0 (Main)	LP3988IMF-3.0/NOPB	MIC5256-3.0YM5-TR
Manufacturer	Texas Instruments	National Semiconductor	Microchip Technology
Product Status	Obsolete	Active	Active
Output Configuration	Positive	Positive	Positive
Output Type	Fixed	Fixed	Fixed
Voltage - Output (Min/Fixed)	3V	3V	3V
Voltage - Input (Max)	6V	6V	6V
Current - Output	150mA	150mA	150mA
Voltage Dropout (Max)	0.15V @ 150mA	0.15V @ 150mA	0.25V @ 150mA
Current - Quiescent (Iq)	120 µA	120 µA	150 µA
Current - Supply (Max)	200 µA	200 µA	Not specified
PSRR	65dB ~ 45dB (1kHz ~ 10kHz)	65dB ~ 45dB (1kHz ~ 10kHz)	60dB ~ 45dB (10Hz ~ 10kHz)
Control Features	Enable, Power Good	Enable, Power Good	Enable
Protection Features	Over Temperature, Short Circuit	Over Temperature, Short Circuit	Over Current, Over Temperature, Under Voltage Lockout (UVLO)
Operating Temperature	-40°C ~ 125°C	-40°C ~ 125°C	-40°C ~ 125°C
Package / Case	SC-74A, SOT-753	SC-74A, SOT-753	SC-74A, SOT-753
Supplier Device Package	SOT-23-5	SOT-23-5	SOT-23-5
RoHS Status	RoHS non-compliant	Not specified	ROHS3 Compliant
Packaging	Not specified	Bulk	Tape & Reel (TR)

Engineering Selection Recommendations

LP3988IMF-3.0/NOPB (National Semiconductor): This part is a parametric equivalent with identical electrical specifications to the main part, including matching dropout voltage (0.15V @ 150mA), quiescent current (120 µA), and control features (Enable, Power Good). The primary distinction is product status: this part is active and currently available. Selection of this substitute eliminates obsolescence risk while maintaining full functional compatibility.

MIC5256-3.0YM5-TR (Microchip Technology): This part is an active substitute that meets all core substitution criteria. Notable differences include a higher dropout voltage (0.25V @ 150mA versus 0.15V), slightly elevated quiescent current (150 µA versus 120 µA), and the absence of a dedicated Power Good output. The MIC5256 includes additional protection features (Over Current and Under Voltage Lockout) not present in the original design. This part carries ROHS3 compliance, addressing environmental regulatory requirements. Selection of this substitute is appropriate for applications where the increased dropout voltage and absence of Power Good functionality do not impact system performance.

Frequently Asked Questions (FAQ)

Q: Can LP3988IMF-3.0/NOPB be used as a direct replacement for LP3988IMF-3.0?

A: Yes. The LP3988IMF-3.0/NOPB maintains identical electrical and mechanical specifications, including output voltage, current rating, dropout voltage, quiescent current, control features, and package type. The primary advantage is active product status and current availability.

Q: What are the key differences between LP3988IMF-3.0 and MIC5256-3.0YM5-TR?

A: Both parts deliver 3V at 150mA in SOT-23-5 packaging. The MIC5256 exhibits higher dropout voltage (0.25V versus 0.15V at 150mA) and slightly higher quiescent current (150 µA versus 120 µA). The MIC5256 lacks a Power Good output but includes Over Current and UVLO protection. The MIC5256 is ROHS3 compliant.

Q: Are there any package compatibility concerns when substituting these parts?

A: All three parts use identical SOT-23-5 packaging (SC-74A, SOT-753). Pin-to-pin compatibility is maintained, allowing direct PCB substitution without layout modifications.

Q: Which substitute should be selected for new designs?

A: Selection depends on specific application requirements. For designs requiring Power Good functionality and minimal dropout voltage, LP3988IMF-3.0/NOPB is preferred. For designs where additional protection features and RoHS3 compliance are priorities, MIC5256-3.0YM5-TR is suitable, provided the higher dropout voltage is acceptable.

Q: What is the impact of the higher dropout voltage in MIC5256-3.0YM5-TR?

A: The MIC5256 requires 0.25V headroom between input and output at 150mA, compared to 0.15V for the original part. This affects minimum input voltage requirements and power dissipation characteristics. Applications with tight input voltage margins must account for this difference.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message