SK34B-TP Equivalent & Substitute Parts

Part Overview

The SK34B-TP is a Schottky rectifier diode manufactured by Micro Commercial Co, rated for 40 V DC reverse voltage and 3 A average rectified current in a DO-214AA (SMB) surface mount package. This part is classified as obsolete, which necessitates identification of active equivalent and substitute components for ongoing design and procurement requirements. The SK34B-TP serves as a fast recovery Schottky diode suitable for applications requiring low forward voltage drop and rapid switching characteristics in surface mount configurations.

Key Parameters

Parameter	Value	Unit
Voltage - DC Reverse (Vr) (Max)	40	V
Current - Average Rectified (Io)	3	A
Voltage - Forward (Vf) (Max) @ If	500 mV @ 3 A	mV
Speed	Fast Recovery ≤ 500ns, > 200mA (Io)	ns
Current - Reverse Leakage @ Vr	500 µA @ 40 V	µA
Package / Case	DO-214AA, SMB	—
Mounting Type	Surface Mount	—
Operating Temperature - Junction	-55°C ~ 125°C	°C
RoHS Status	ROHS3 Compliant	—
Moisture Sensitivity Level (MSL)	1 (Unlimited)	—

Substitute Part Grouping Explanation

Substitution of the SK34B-TP is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

Voltage - DC Reverse (Vr) (Max): 40 V minimum
Current - Average Rectified (Io): 3 A minimum
Technology: Schottky
Package / Case: DO-214AA (SMB) or compatible surface mount package
Mounting Type: Surface Mount
Speed: Fast Recovery ≤ 500ns, > 200mA (Io)

Secondary Compatibility Factors:

Voltage - Forward (Vf) (Max) @ If: 500 mV @ 3 A or lower
Current - Reverse Leakage @ Vr: 500 µA @ 40 V or lower
Operating Temperature - Junction: -55°C minimum to 125°C minimum
RoHS3 Compliance
MSL 1 (Unlimited)

Substitute parts are grouped into three categories:

Direct Equivalents: Identical electrical specifications and active product status (SK34B-LTP)
Parametric Equivalents: Matching core electrical parameters with enhanced specifications or automotive qualification (SK34BHE3-LTP, B340B-13-F)
Similar Alternatives: Matching voltage, current, and package with minor parameter variations (B340LB-13-F, B340LB-E3/52T, B340LB-E3/5BT, CDBB340-G, CMSH3-40M TR13 PBFREE)

Parts with voltage ratings exceeding 40 V (MBRS360BT3G at 60 V) and parts with different package types (SS34 in SMA package) are listed as similar alternatives but require design verification for application compatibility.

Parameter Comparison

Manufacturer Part Number	Manufacturer	Vr (Max) [V]	Io [A]	Vf (Max) @ If [mV]	Reverse Leakage @ Vr [µA]	Package	Product Status	Tj (Max) [°C]
SK34B-TP	Micro Commercial Co	40	3	500 @ 3A	500 @ 40V	DO-214AA, SMB	Obsolete	125
SK34B-LTP	Micro Commercial Co	40	3	500 @ 3A	500 @ 40V	DO-214AA, SMB	Active	150
SK34BHE3-LTP	Micro Commercial Co	40	3	500 @ 3A	100 @ 40V	DO-214AA, SMB	Active	125
B340LB-13-F	Diodes Incorporated	40	3	450 @ 3A	2000 @ 40V	DO-214AA, SMB	Active	125
B340B-13-F	Diodes Incorporated	40	3	500 @ 3A	500 @ 40V	DO-214AA, SMB	Active	150
B340LB-E3/52T	Vishay General Semiconductor - Diodes Division	40	3	450 @ 3A	400 @ 40V	DO-214AA, SMB	Active	150
B340LB-E3/5BT	Vishay General Semiconductor - Diodes Division	40	3	450 @ 3A	400 @ 40V	DO-214AA, SMB	Active	150
CDBB340-G	Comchip Technology	40	3	500 @ 3A	500 @ 40V	DO-214AA, SMB	Not For New Designs	125
CMSH3-40M TR13 PBFREE	Central Semiconductor Corp	40	3	550 @ 3A	500 @ 40V	DO-214AA, SMB	Active	150
MBRS360BT3G	onsemi	60	3	630 @ 3A	30 @ 60V	DO-214AA, SMB	Active	175
SS34	MDD	40	3	—	500 @ 40V	DO-214AC, SMA	Active	125

Engineering Selection Recommendations

Recommended Direct Replacement:

SK34B-LTP (Micro Commercial Co) is the primary recommended substitute for SK34B-TP. This part maintains identical electrical specifications (40 V, 3 A, 500 mV forward voltage) and is in active product status. The SK34B-LTP offers an extended maximum junction temperature of 150°C compared to the obsolete SK34B-TP (125°C), providing improved thermal margin. Both parts are ROHS3 compliant with MSL 1 rating and are available in the same DO-214AA SMB package.

Automotive-Qualified Alternative:

SK34BHE3-LTP (Micro Commercial Co) is suitable for applications requiring automotive-grade components. This part carries AEC-Q101 qualification and demonstrates superior reverse leakage characteristics (100 µA @ 40 V versus 500 µA @ 40 V in the original). The maximum junction temperature remains at 125°C, matching the SK34B-TP specification.

Cross-Manufacturer Alternatives:

B340B-13-F (Diodes Incorporated) provides equivalent electrical performance with active product status and extended temperature rating (150°C). This part is automotive-qualified (AEC-Q101) and maintains 500 mV forward voltage specification.

B340LB-E3/52T and B340LB-E3/5BT (Vishay General Semiconductor - Diodes Division) offer improved forward voltage characteristics (450 mV @ 3 A) with extended temperature range (-65°C to 150°C). These parts are available in different packaging formats (Cut Tape and Tape & Reel).

Parts Not Recommended for New Designs:

CDBB340-G (Comchip Technology) is classified as "Not For New Designs" and should not be selected for new applications despite electrical equivalence.

Voltage-Rated Alternatives:

MBRS360BT3G (onsemi) operates at 60 V reverse voltage, exceeding the 40 V requirement of SK34B-TP. This part is suitable only for applications where higher voltage rating is required or beneficial. Forward voltage (630 mV @ 3 A) and reverse leakage (30 µA @ 60 V) differ significantly from the original specification.

Package Variant:

SS34 (MDD) is a 40 V, 3 A Schottky diode in DO-214AC (SMA) package rather than SMB. This part is suitable only if the application circuit board layout accommodates SMA package geometry.

Frequently Asked Questions (FAQ)

Q: Can SK34B-LTP be used as a direct replacement for SK34B-TP without circuit modification?

A: Yes. SK34B-LTP is electrically equivalent to SK34B-TP with identical voltage (40 V), current (3 A), and forward voltage (500 mV @ 3 A) specifications. Both use the DO-214AA SMB package. The extended temperature rating of SK34B-LTP (150°C versus 125°C) provides additional thermal margin without requiring design changes.

Q: What is the difference between SK34B-LTP and SK34BHE3-LTP?

A: Both parts are 40 V, 3 A Schottky diodes in SMB packages from Micro Commercial Co. SK34BHE3-LTP includes automotive qualification (AEC-Q101) and exhibits lower reverse leakage (100 µA @ 40 V versus 500 µA @ 40 V). SK34BHE3-LTP maintains the original 125°C maximum junction temperature, while SK34B-LTP extends to 150°C. Selection depends on automotive requirements and thermal operating conditions.

Q: Why does B340LB-13-F show 2000 µA reverse leakage while SK34B-TP shows 500 µA?

A: Reverse leakage specifications vary among manufacturers due to different measurement conditions and device design. B340LB-13-F (Diodes Incorporated) exhibits higher reverse leakage at 2000 µA @ 40 V compared to SK34B-TP at 500 µA @ 40 V. This difference may impact applications sensitive to leakage current. B340LB-E3/52T from Vishay provides a middle ground at 400 µA @ 40 V.

Q: Can MBRS360BT3G replace SK34B-TP in a 40 V application?

A: MBRS360BT3G is rated for 60 V reverse voltage, which exceeds the 40 V requirement of SK34B-TP. While the higher voltage rating provides design margin, the forward voltage (630 mV @ 3 A) is significantly higher than SK34B-TP (500 mV @ 3 A), resulting in increased power dissipation. MBRS360BT3G is suitable only if the application specifically requires 60 V rating or if the higher forward voltage drop is acceptable.

Q: What is the difference between B340LB-E3/52T and B340LB-E3/5BT?

A: Both parts are electrically identical 40 V, 3 A Schottky diodes from Vishay with 450 mV forward voltage and 400 µA reverse leakage. The difference is packaging format: B340LB-E3/52T is supplied in Cut Tape (CT) & Digi-Reel format, while B340LB-E3/5BT is supplied in Tape & Reel (TR) format. Selection depends on procurement and assembly equipment compatibility.

Q: Is SS34 compatible with SK34B-TP?

A: SS34 is electrically compatible (40 V, 3 A, Schottky technology) but uses a different package: DO-214AC (SMA) instead of DO-214AA (SMB). SMA and SMB packages have different footprints and cannot be used interchangeably on the same circuit board without layout redesign. SS34 is suitable only if the application circuit board is designed for SMA package geometry.

Q: Why is CDBB340-G marked as "Not For New Designs"?

A: CDBB340-G (Comchip Technology) is classified as "Not For New Designs" by the manufacturer, indicating that the product line is being phased out or superseded. While the part may be electrically equivalent, new designs should select from active product status alternatives such as SK34B-LTP, B340B-13-F, or B340LB-E3/52T to ensure long-term availability and manufacturer support.

Q: What does AEC-Q101 qualification mean for automotive applications?

A: AEC-Q101 is an automotive industry standard qualification for discrete semiconductors. Parts carrying this qualification (such as SK34BHE3-LTP and B340B-13-F) have undergone rigorous testing for reliability, temperature cycling, and performance consistency required in automotive environments. Selection of AEC-Q101 qualified parts is mandatory for automotive applications.

Q: Can I use a substitute part with higher maximum junction temperature than SK34B-TP?

A: Yes. A substitute part with higher maximum junction temperature (such as SK34B-LTP at 150°C versus SK34B-TP at 125°C) provides additional thermal margin and is suitable for the same application. The higher temperature rating does not negatively impact performance in applications operating below the original temperature limit.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message