2N4401RLRM Equivalent & Substitute Parts

Part Overview

The 2N4401RLRM is an NPN bipolar junction transistor manufactured by onsemi, rated for 40 V collector-emitter breakdown voltage and 600 mA maximum collector current. This device is designed for through-hole mounting in the TO-92-3 package and operates across a temperature range of -55°C to 150°C. The 2N4401RLRM is classified as obsolete, making identification of equivalent and substitute parts essential for ongoing design support and production continuity. Direct replacements and functionally equivalent alternatives are available from multiple manufacturers with active product status.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Voltage - Collector Emitter Breakdown (Max)	40	V
Current - Collector (Ic) (Max)	600	mA
Vce Saturation (Max) @ Ib, Ic	750 mV @ 50 mA, 500 mA	—
DC Current Gain (hFE) (Min) @ Ic, Vce	100 @ 150 mA, 1 V	—
Power - Max	625	mW
Frequency - Transition	250	MHz
Operating Temperature	-55 to 150	°C (TJ)
Mounting Type	Through Hole	—
Package / Case	TO-226-3, TO-92-3 Long Body (Formed Leads)	—

Substitute Part Grouping Explanation

Substitution of the 2N4401RLRM is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

Transistor Type: NPN configuration required
Voltage - Collector Emitter Breakdown (Max): Minimum 40 V
Current - Collector (Ic) (Max): Minimum 600 mA
DC Current Gain (hFE) (Min): Minimum 100 @ specified conditions
Power - Max: Minimum 625 mW
Frequency - Transition: Minimum 250 MHz
Operating Temperature Range: Must encompass -55°C to 150°C

Mechanical Compatibility Criteria:

Mounting Type: Through Hole required
Package / Case: TO-92-3 or TO-226-3 compatible

Substitute parts are classified into two categories:

Direct Substitutes maintain identical electrical specifications and package compatibility. These parts are pin-for-pin replacements with no circuit modifications required.

Similar Substitutes meet or exceed the electrical requirements but may have different secondary specifications (such as higher transition frequency or different saturation voltage characteristics). These parts are functionally compatible but require verification of application-specific requirements.

Parameter Comparison

Part Number	Manufacturer	Vce Breakdown (Max)	Ic (Max)	hFE (Min)	Power (Max)	Frequency	Package	Product Status
2N4401RLRM	onsemi	40 V	600 mA	100 @ 150 mA, 1 V	625 mW	250 MHz	TO-92-3	Obsolete
2N4401TA	onsemi	40 V	600 mA	100 @ 150 mA, 1 V	625 mW	250 MHz	TO-92-3	Active
2N4401TAR	onsemi	40 V	600 mA	100 @ 150 mA, 1 V	625 mW	250 MHz	TO-92-3	Active
2N4401TF	Fairchild Semiconductor	40 V	600 mA	100 @ 150 mA, 1 V	625 mW	250 MHz	TO-92-3	Active
2N4401TFR	onsemi	40 V	600 mA	100 @ 150 mA, 1 V	625 mW	250 MHz	TO-92-3	Active
KSP2222ATA	Fairchild Semiconductor	40 V	600 mA	100 @ 150 mA, 10 V	625 mW	300 MHz	TO-92-3	Active
PN2222TA	onsemi	30 V	600 mA	100 @ 150 mA, 10 mV	625 mW	300 MHz	TO-92-3	Last Time Buy
PN2222TF	Fairchild Semiconductor	30 V	600 mA	100 @ 150 mA, 10 mV	625 mW	300 MHz	TO-92-3	Active
2N4401-AP	Micro Commercial Co	40 V	600 mA	100 @ 150 mA, 1 V	600 mW	250 MHz	TO-92-3	Obsolete

Engineering Selection Recommendations

Direct Replacement Priority:

The 2N4401TA, 2N4401TAR, 2N4401TF, and 2N4401TFR are direct electrical and mechanical equivalents to the 2N4401RLRM. These parts maintain identical specifications across all critical parameters and require no circuit modifications. Among these options, 2N4401TA and 2N4401TFR are recommended as primary selections due to active product status and high inventory availability.

Compliance Considerations:

The 2N4401RLRM is RoHS non-compliant. Direct substitutes 2N4401TA, 2N4401TAR, and 2N4401TFR are ROHS3 compliant, providing improved environmental and regulatory alignment for new designs and production runs. The 2N4401TF from Fairchild Semiconductor is active but compliance status is not specified in available data.

Alternative Substitutes:

The KSP2222ATA meets the 40 V breakdown voltage requirement and exceeds the transition frequency specification at 300 MHz. However, the DC current gain measurement condition differs (10 V versus 1 V), and the saturation voltage specification is higher at 1 V. This part is suitable for applications where higher frequency performance is beneficial and saturation voltage tolerance permits.

The PN2222TA and PN2222TF are not recommended as direct substitutes. These parts have a maximum collector-emitter breakdown voltage of 30 V, which is below the 40 V requirement of the 2N4401RLRM. Application of these parts in circuits designed for 40 V operation presents reliability risk.

The 2N4401-AP from Micro Commercial Co is obsolete and should not be selected for new designs despite meeting electrical specifications.

Frequently Asked Questions (FAQ)

Q: Can the 2N4401TA directly replace the 2N4401RLRM without circuit modifications?

A: Yes. The 2N4401TA is a direct electrical and mechanical equivalent. All critical parameters including voltage rating, current rating, gain, power dissipation, and frequency response are identical. The TO-92-3 package is pin-compatible. No circuit modifications are required.

Q: What is the difference between 2N4401TA and 2N4401TAR?

A: Both parts are manufactured by onsemi and maintain identical electrical specifications. The primary difference is packaging format: 2N4401TA is supplied in Cut Tape (CT) packaging, while 2N4401TAR is also supplied in Cut Tape (CT). Both are active products with high inventory availability.

Q: Why is the PN2222TA listed as a similar substitute if it has a lower voltage rating?

A: The PN2222TA is listed as a similar substitute based on shared mechanical compatibility and collector current rating. However, the 30 V maximum collector-emitter breakdown voltage is below the 40 V specification of the 2N4401RLRM. This part is not suitable for applications requiring the full 40 V rating and should only be considered for circuits operating below 30 V.

Q: Is the KSP2222ATA a suitable replacement for the 2N4401RLRM?

A: The KSP2222ATA meets the 40 V voltage requirement and exceeds the frequency specification. However, the saturation voltage is specified at 1 V compared to 0.75 V for the 2N4401RLRM, and the DC current gain measurement condition differs. The KSP2222ATA is functionally compatible but introduces different switching characteristics. Application-specific verification is necessary.

Q: What is the significance of the 2N4401RLRM being classified as obsolete?

A: Obsolete status indicates the part is no longer manufactured and existing inventory is limited. The 2N4401RLRM has 665 pieces in stock. Direct substitutes with active product status (2N4401TA, 2N4401TFR) are recommended for design continuity and long-term supply assurance.

Q: Are there compliance differences between the 2N4401RLRM and its direct substitutes?

A: Yes. The 2N4401RLRM is RoHS non-compliant. Direct substitutes 2N4401TA, 2N4401TAR, and 2N4401TFR are ROHS3 compliant. For applications subject to RoHS requirements, these compliant alternatives are necessary.

Q: Can the 2N4401TF from Fairchild Semiconductor be used interchangeably with onsemi versions?

A: Yes. The 2N4401TF maintains identical electrical specifications and TO-92-3 package compatibility. It is manufactured by Fairchild Semiconductor and carries active product status. Interchangeability is supported from an electrical and mechanical standpoint.

Q: What packaging options are available for 2N4401 equivalents?

A: Direct equivalents are available in Cut Tape (CT) packaging (2N4401TA, 2N4401TAR, 2N4401TFR). The 2N4401TF is supplied in Bulk packaging. All maintain the TO-92-3 through-hole package format. Packaging selection depends on procurement and assembly requirements.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message