SS12 Schottky Diode 20V 1A DO-214AC Equivalent & Substitute Parts

Part Overview

The onsemi SS12 is a Schottky rectifier diode rated for 20 V DC reverse voltage and 1 A average rectified current in a DO-214AC (SMA) surface mount package. This component is classified as "Not For New Designs," indicating it has reached end-of-life status. Identifying equivalent and substitute parts is necessary for ongoing production support, legacy system maintenance, and design flexibility when the primary part becomes unavailable.

Key Parameters

Parameter	Value	Unit
Voltage - DC Reverse (Vr) (Max)	20	V
Current - Average Rectified (Io)	1	A
Voltage - Forward (Vf) (Max) @ If	500 mV @ 1 A	mV
Speed	Fast Recovery ≤ 500ns, > 200mA (Io)	ns
Current - Reverse Leakage @ Vr	200	µA @ 20 V
Mounting Type	Surface Mount	—
Package / Case	DO-214AC, SMA	—
Operating Temperature - Junction	-65 to 125	°C
Technology	Schottky	—
RoHS Status	ROHS3 Compliant	—

Substitute Part Grouping Explanation

Substitution of the SS12 Schottky diode is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

Voltage - DC Reverse (Vr) (Max): Must equal or exceed 20 V
Current - Average Rectified (Io): Must equal or exceed 1 A
Technology: Schottky rectifier diode
Mounting Type: Surface Mount
Package / Case: DO-214AC (SMA) or compatible surface mount package

Secondary Compatibility Factors:

Voltage - Forward (Vf) (Max) @ If: Acceptable range 450 mV to 550 mV @ rated current
Speed: Fast Recovery ≤ 500ns, > 200mA (Io)
Operating Temperature - Junction: Minimum -55°C to maximum 150°C
RoHS Status: ROHS3 Compliant

Parts are grouped into three categories:

Direct Equivalents: Identical electrical ratings (20 V, 1 A) with matching forward voltage and reverse leakage characteristics in DO-214AC package.

Pin-Compatible Substitutes: Identical electrical ratings (20 V, 1 A) in DO-214AC or SMA package with acceptable parameter variations.

Higher Current Alternatives: Rated for 20 V with current ratings of 2 A or 3 A, suitable for applications with current margin requirements.

Parts with different package types (SOD-123W) or significantly different voltage ratings (40 V) are listed for reference but require circuit board layout modifications or application re-evaluation.

Parameter Comparison

Manufacturer Part Number	Manufacturer	Vr (Max) [V]	Io [A]	Vf (Max) @ If [mV]	Reverse Leakage @ Vr [µA]	Package	Temp Range [°C]	Product Status
SS12	onsemi	20	1	500 @ 1A	200 @ 20V	DO-214AC (SMA)	-65 to 125	Not For New Designs
MBRA120ET3G	onsemi	20	1	530 @ 1A	10 @ 20V	DO-214AC (SMA)	-55 to 150	Active
SS12-E3/61T	Vishay General Semiconductor - Diodes Division	20	1	500 @ 1A	200 @ 20V	DO-214AC (SMA)	-65 to 125	Active
B120-13-F	Diodes Incorporated	20	1	500 @ 1A	500 @ 20V	DO-214AC (SMA)	-65 to 150	Active
B120Q-13-F	Diodes Incorporated	20	1	500 @ 1A	500 @ 20V	DO-214AC (SMA)	-65 to 150	Active
B220A-13-F	Diodes Incorporated	20	2	500 @ 2A	500 @ 20V	DO-214AC (SMA)	-65 to 150	Active
B220AQ-13-F	Diodes Incorporated	20	2	500 @ 2A	500 @ 20V	DO-214AC (SMA)	-65 to 150	Active
B320A-13-F	Diodes Incorporated	20	3	500 @ 3A	500 @ 20V	DO-214AC (SMA)	-55 to 150	Active
PMEG2010BER,115	Nexperia USA Inc.	20	1	450 @ 1A	50 @ 20V	SOD-123W	—	Active
STPS140A	STMicroelectronics	40	1	550 @ 1A	12 @ 40V	DO-214AC (SMA)	—	Active

Engineering Selection Recommendations

Direct Equivalent (Recommended for Legacy Support):

SS12-E3/61T (Vishay General Semiconductor - Diodes Division) is the primary direct equivalent. It maintains identical electrical specifications (20 V, 1 A, 500 mV forward voltage, 200 µA reverse leakage) and operates across the same temperature range (-65°C to 125°C). This part is in Active product status and is available in Tape & Reel packaging. Selection of this part eliminates the need for circuit re-evaluation or board layout modifications.

Primary Active Substitute (Same Electrical Class):

MBRA120ET3G (onsemi) provides equivalent voltage and current ratings with improved reverse leakage characteristics (10 µA versus 200 µA). Forward voltage is slightly elevated at 530 mV. Operating temperature range extends to 150°C. This part is in Active status and represents a direct pin-compatible replacement suitable for new production runs of legacy designs.

Pin-Compatible Alternatives (Same Package, 1 A Rating):

B120-13-F and B120Q-13-F (Diodes Incorporated) both meet the 20 V, 1 A electrical requirements with identical forward voltage (500 mV). B120Q-13-F includes AEC-Q101 automotive qualification. Both parts operate to 150°C and are in Active status. Higher reverse leakage (500 µA) is acceptable in most applications. B120Q-13-F is suitable for automotive and mission-critical applications.

Higher Current Alternatives (Same Voltage, Increased Current Margin):

B220A-13-F and B220AQ-13-F (Diodes Incorporated) are rated for 20 V, 2 A, providing 2× current capacity. B220AQ-13-F includes AEC-Q101 qualification. These parts are suitable for applications requiring additional thermal or current margin without voltage re-rating.

B320A-13-F (Diodes Incorporated) is rated for 20 V, 3 A, providing 3× current capacity with AEC-Q101 automotive qualification. Operating temperature range is -55°C to 150°C.

Alternative Package Consideration:

PMEG2010BER,115 (Nexperia USA Inc.) provides 20 V, 1 A in SOD-123W package with superior forward voltage (450 mV) and reverse leakage (50 µA). This part requires board layout modification due to different package geometry and is suitable only when PCB redesign is feasible.

Higher Voltage Alternative (Not Recommended for Direct Substitution):

STPS140A (STMicroelectronics) is rated for 40 V, 1 A in DO-214AC package. This part is suitable only for applications where higher voltage margin is required and forward voltage elevation (550 mV) is acceptable. Direct substitution in 20 V circuits is not recommended without circuit analysis.

Frequently Asked Questions (FAQ)

Q: Can I use MBRA120ET3G as a direct replacement for SS12?

A: Yes. MBRA120ET3G meets all electrical requirements (20 V, 1 A) with identical forward voltage (500 mV at 1 A) and is pin-compatible in the DO-214AC package. The lower reverse leakage (10 µA versus 200 µA) is an improvement. Operating temperature range extends to 150°C. This is the recommended active substitute.

Q: What is the difference between B120-13-F and B120Q-13-F?

A: Both parts are electrically identical (20 V, 1 A, 500 mV forward voltage). B120Q-13-F includes AEC-Q101 automotive qualification and is supplied in Tape & Reel packaging. B120-13-F is supplied in Cut Tape & Digi-Reel packaging. Select B120Q-13-F for automotive or mission-critical applications.

Q: Can I use B220A-13-F (2 A) instead of SS12 (1 A)?

A: Yes. B220A-13-F is rated for 20 V, 2 A and is pin-compatible in the DO-214AC package. The higher current rating provides additional thermal margin and is suitable for applications where the original 1 A rating is marginal. Forward voltage remains at 500 mV. No circuit modifications are required.

Q: Why is STPS140A listed if it has a different voltage rating?

A: STPS140A is rated for 40 V, 1 A and is included for reference only. It is not a direct substitute for the 20 V SS12. Use STPS140A only in applications where higher reverse voltage is required. Direct substitution in 20 V circuits requires circuit analysis due to forward voltage elevation (550 mV).

Q: Can I use PMEG2010BER,115 as a replacement?

A: PMEG2010BER,115 meets the 20 V, 1 A electrical requirements with superior forward voltage (450 mV) and reverse leakage (50 µA). However, it is packaged in SOD-123W, which has different pin spacing and footprint than the DO-214AC package. This part requires PCB layout modification and is suitable only when board redesign is feasible.

Q: What does "Not For New Designs" mean for the SS12?

A: "Not For New Designs" indicates the SS12 has reached end-of-life status. onsemi no longer recommends this part for new circuit designs. For ongoing production of legacy systems, use active substitutes such as SS12-E3/61T (Vishay) or MBRA120ET3G (onsemi). For new designs, select from the active alternatives listed in this document.

Q: Are all listed substitutes RoHS3 compliant?

A: Yes. All substitute parts listed in this document are RoHS3 compliant and REACH unaffected, matching the compliance status of the original SS12.

Q: What is the difference between Cut Tape and Tape & Reel packaging?

A: Cut Tape (CT) & Digi-Reel packaging is supplied in smaller quantities on cut tape. Tape & Reel (TR) packaging is supplied in continuous reel format for high-volume automated assembly. Both formats contain the same component. Select based on production volume and assembly equipment compatibility.

Q: Can I mix different manufacturers' parts in the same production run?

A: Yes, provided all parts meet the specified electrical parameters (20 V, 1 A, 500 mV forward voltage, fast recovery speed) and are in the same package (DO-214AC). However, for consistency and traceability, it is recommended to standardize on a single manufacturer part number per production batch.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message