SF11-T Equivalent & Substitute Parts

Part Overview

The SF11-T is a general-purpose rectifier diode manufactured by Diodes Incorporated, rated for 50 V DC reverse voltage and 1 A average rectified current in a DO-41 through-hole package. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing production and maintenance applications. The SF11-T features fast recovery characteristics with a reverse recovery time of 35 nanoseconds, distinguishing it from standard recovery alternatives in the substitute pool.

Key Parameters

Parameter	Value
Voltage - DC Reverse (Vr) (Max)	50 V
Current - Average Rectified (Io)	1 A
Voltage - Forward (Vf) (Max) @ If	975 mV @ 1 A
Reverse Recovery Time (trr)	35 ns
Current - Reverse Leakage @ Vr	5 µA @ 50 V
Speed Classification	Fast Recovery ≤ 500 ns, > 200 mA (Io)
Mounting Type	Through Hole
Package / Case	DO-204AL, DO-41, Axial
Operating Temperature - Junction	-65°C ~ 175°C
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution of the SF11-T is determined by the following critical parameters:

Electrical Compatibility Requirements:

Voltage - DC Reverse (Vr) (Max): 50 V minimum
Current - Average Rectified (Io): 1 A minimum
Current - Reverse Leakage @ Vr: 5 µA @ 50 V maximum
Mounting Type: Through Hole
Package / Case: DO-204AL, DO-41, or Axial

Performance Considerations:

Forward voltage drop (Vf) at 1 A: Substitute parts range from 1.0 V to 1.1 V, compared to the SF11-T at 975 mV
Reverse recovery time (trr): The SF11-T operates at 35 ns (fast recovery). Substitute parts operate at 2 µs (standard recovery) or are unspecified
Operating temperature range: SF11-T operates -65°C to 175°C; most substitutes operate -55°C to 150°C

Compliance and Availability:

RoHS3 compliance required
Product status: Active or Discontinued at DiGi Electronics preferred over Obsolete
Inventory availability: All substitute parts have stock quantities ranging from 845 to 8238 pieces

The substitute parts listed below meet the minimum electrical requirements but differ in recovery speed classification and operating temperature range. Selection depends on application-specific requirements for switching speed and thermal performance.

Parameter Comparison

Part Number	Manufacturer	Vr (Max)	Io	Vf (Max) @ 1A	Speed Classification	trr	Tj (Operating)	Product Status	Inventory
SF11-T	Diodes Incorporated	50 V	1 A	975 mV	Fast Recovery ≤ 500 ns	35 ns	-65°C ~ 175°C	Obsolete	871 Pcs
1N4001G	Taiwan Semiconductor Corporation	50 V	1 A	1 V	Standard Recovery > 500 ns	Unspecified	-55°C ~ 150°C	Active	1492 Pcs
1N4001-BP	Micro Commercial Co	50 V	1 A	1 V	Standard Recovery > 500 ns	2 µs	-55°C ~ 150°C	Active	845 Pcs
1N4001-E3/54	Vishay General Semiconductor - Diodes Division	50 V	1 A	1.1 V	Standard Recovery > 500 ns	Unspecified	-55°C ~ 150°C	Active	1450 Pcs
1N4001-E3/73	Vishay General Semiconductor - Diodes Division	50 V	1 A	1.1 V	Standard Recovery > 500 ns	Unspecified	-55°C ~ 150°C	Active	1428 Pcs
1N4001-TP	Micro Commercial Co	50 V	1 A	1.1 V	Standard Recovery > 500 ns	2 µs	-55°C ~ 150°C	Not For New Designs	1672 Pcs
1N4001G A0G	Taiwan Semiconductor Corporation	50 V	1 A	1 V	Standard Recovery > 500 ns	Unspecified	-55°C ~ 150°C	Active	1125 Pcs
1N4001G R0G	Taiwan Semiconductor Corporation	50 V	1 A	1 V	Standard Recovery > 500 ns	Unspecified	-55°C ~ 150°C	Discontinued at DiGi Electronics	8238 Pcs
1N4001GP-E3/54	Vishay General Semiconductor - Diodes Division	50 V	1 A	1.1 V	Standard Recovery > 500 ns	2 µs	-65°C ~ 175°C	Active	7607 Pcs
1N4001RLG	onsemi	50 V	1 A	1.1 V	Standard Recovery > 500 ns	Unspecified	-65°C ~ 175°C	Not For New Designs	1790 Pcs

Engineering Selection Recommendations

Primary Substitutes (Active Status, Full Temperature Range):

The 1N4001GP-E3/54 manufactured by Vishay General Semiconductor - Diodes Division is the preferred substitute. It maintains the full operating temperature range of -65°C to 175°C matching the SF11-T, carries Active product status, and provides the highest inventory availability at 7607 pieces. This part is suitable for applications requiring thermal performance equivalent to the original SF11-T.

Secondary Substitutes (Active Status, Reduced Temperature Range):

The 1N4001G variants (standard and A0G) from Taiwan Semiconductor Corporation and the 1N4001-E3/54 and 1N4001-E3/73 from Vishay are Active products with substantial inventory. These parts operate within -55°C to 150°C, which is acceptable for most general-purpose applications but does not extend to the full temperature extremes of the SF11-T.

Compatibility Considerations:

All listed substitutes meet the minimum electrical requirements of 50 V reverse voltage and 1 A average rectified current. However, the SF11-T operates as a fast recovery diode (35 ns trr), while all substitutes are standard recovery devices (2 µs trr or unspecified). Applications sensitive to switching speed or high-frequency operation may experience performance differences.

Obsolescence and Compliance:

The SF11-T is classified as Obsolete. All substitute parts carry ROHS3 compliance and REACH Unaffected status, ensuring regulatory alignment for new designs and production continuity.

Not Recommended for New Designs:

The 1N4001-TP and 1N4001RLG carry "Not For New Designs" status and should be used only for legacy system maintenance or repair applications.

Frequently Asked Questions (FAQ)

Q: Can the 1N4001G directly replace the SF11-T in all applications?

A: The 1N4001G meets the core electrical specifications (50 V, 1 A, through-hole DO-41 package) and is electrically compatible. However, it operates as a standard recovery diode with unspecified reverse recovery time, compared to the SF11-T's 35 ns fast recovery. Applications requiring fast switching or operating at high frequencies may exhibit different performance. The 1N4001G also operates within -55°C to 150°C versus the SF11-T's -65°C to 175°C range.

Q: What is the difference between fast recovery and standard recovery diodes?

A: The SF11-T is specified as fast recovery with a reverse recovery time of 35 nanoseconds. Standard recovery substitutes operate at 2 microseconds or longer. Fast recovery diodes switch off more quickly, reducing switching losses in high-frequency applications. Standard recovery diodes are suitable for low-frequency rectification and general-purpose applications where switching speed is not critical.

Q: Why does the 1N4001GP-E3/54 have a higher forward voltage drop than the SF11-T?

A: The SF11-T specifies 975 mV forward voltage at 1 A, while the 1N4001GP-E3/54 specifies 1.1 V at 1 A. This 125 mV difference reflects different semiconductor materials and manufacturing processes. In most general-purpose rectification applications, this difference is negligible. Applications with tight power budget constraints should calculate the impact of the additional voltage drop.

Q: Are all substitute parts RoHS3 compliant?

A: Yes, all listed substitute parts carry ROHS3 Compliant status, ensuring compliance with lead-free and hazardous substance restrictions.

Q: What is the significance of the packaging variants (DO-41, DO-204AL, Axial)?

A: All parts listed are through-hole axial-lead diodes. DO-41 and DO-204AL refer to the same physical package with different naming conventions. The axial package designation confirms lead configuration. All substitutes are mechanically compatible with the SF11-T footprint.

Q: Can I use the 1N4001RLG as a substitute?

A: The 1N4001RLG meets electrical specifications and maintains the full -65°C to 175°C operating range. However, it carries "Not For New Designs" status, indicating onsemi has designated this part for legacy applications only. It is suitable for repair and maintenance of existing systems but should not be selected for new product designs.

Q: Which substitute offers the best inventory availability?

A: The 1N4001G R0G from Taiwan Semiconductor Corporation has the highest inventory at 8238 pieces. However, this part is listed as "Discontinued at DiGi Electronics," indicating limited future availability. The 1N4001GP-E3/54 with 7607 pieces and Active status provides the best combination of availability and long-term supply assurance.

Q: Does operating temperature range affect my selection?

A: The SF11-T operates from -65°C to 175°C. The 1N4001GP-E3/54 and 1N4001RLG maintain this full range. Other substitutes operate within -55°C to 150°C. If your application requires operation at temperatures below -55°C or above 150°C, select the 1N4001GP-E3/54 or 1N4001RLG. For standard industrial and consumer applications operating within 0°C to 70°C, the reduced temperature range substitutes are fully adequate.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message