SS12FP Schottky Diode Equivalent & Substitute Parts

Part Overview

The SS12FP is a surface mount Schottky rectifier diode manufactured by onsemi, rated for 20 V DC reverse voltage and 1 A average rectified current. The device is packaged in SOD-123HE and features fast recovery characteristics with a maximum forward voltage of 450 mV at 1 A. The SS12FP holds automotive grade qualification under AEC-Q101 and is RoHS3 compliant.

The SS12FP is designated as "Not For New Designs," indicating that onsemi has discontinued active development for this part number. This status necessitates identification of functionally equivalent alternatives that maintain electrical performance and compliance requirements for existing applications or new designs requiring similar specifications.

Substiute Parts

SS12FP

onsemiIn Stock: 155356SS12FP Datasheet

Current PartRFQ

SS1P3LHM3/84A

Vishay General Semiconductor - Diodes DivisionIn Stock: 1322SS1P3LHM3/84A Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SS12FP is determined by electrical and mechanical compatibility within the following parameters:

Primary Substitution Criteria:

• Technology: Schottky diode
• Current Rating: 1 A average rectified current (Io)
• Voltage Rating: Minimum 20 V DC reverse voltage (Vr)
• Forward Voltage: Maximum 450 mV @ 1 A
• Speed: Fast recovery ≤ 500ns, > 200mA (Io)
• Grade: Automotive qualification (AEC-Q101)
• Compliance: RoHS3 compliant
• Temperature Range: -55°C to 150°C junction operating temperature

The SS1P3LHM3/84A manufactured by Vishay General Semiconductor - Diodes Division qualifies as a substitute part. This device exceeds the minimum voltage requirement (30 V vs. 20 V), maintains identical current rating (1 A), forward voltage specification (450 mV @ 1 A), and recovery speed characteristics. The substitute maintains automotive grade status with AEC-Q101 qualification and RoHS3 compliance. Package differences exist (DO-220AA vs. SOD-123H), requiring mechanical verification for board layout compatibility.

Parameter Comparison

Engineering Selection Recommendations

The SS1P3LHM3/84A is electrically compatible with the SS12FP for applications requiring 20 V or lower reverse voltage operation. The substitute part provides higher voltage rating (30 V), which does not degrade performance in circuits designed for 20 V operation. Both devices maintain identical forward voltage characteristics (450 mV @ 1 A) and recovery speed specifications, ensuring functional equivalence in rectification and switching applications.

Both parts hold automotive grade qualification under AEC-Q101 and maintain RoHS3 compliance, satisfying regulatory and quality requirements for automotive and industrial applications. The SS1P3LHM3/84A carries "Active" product status, ensuring long-term availability and continued manufacturer support, whereas the SS12FP is designated "Not For New Designs."

Package differences between SOD-123H (SS12FP) and DO-220AA (SS1P3LHM3/84A) require mechanical verification. Board layout, thermal management, and PCB footprint compatibility must be evaluated before implementation. The DO-220AA package may provide improved thermal performance due to larger lead geometry, which can be advantageous in high-current or high-temperature applications.

Frequently Asked Questions (FAQ)

Q: Can the SS1P3LHM3/84A directly replace the SS12FP without circuit modification?

A: Electrical substitution is valid. The SS1P3LHM3/84A maintains identical forward voltage (450 mV @ 1 A) and recovery speed characteristics. However, package differences (DO-220AA vs. SOD-123H) require PCB footprint redesign. No circuit topology changes are necessary if mechanical compatibility is addressed.

Q: What is the significance of the higher voltage rating (30 V vs. 20 V) on the substitute part?

A: The higher voltage rating on the SS1P3LHM3/84A does not affect performance in 20 V applications. Schottky diodes operate within their rated voltage envelope; exceeding the minimum requirement provides design margin and does not introduce functional degradation.

Q: Are both parts suitable for automotive applications?

A: Yes. Both the SS12FP and SS1P3LHM3/84A hold automotive grade qualification under AEC-Q101 and are RoHS3 compliant. Both maintain operating temperature ranges of -55°C to 150°C junction temperature, meeting automotive environmental and reliability standards.

Q: Why is the SS12FP marked "Not For New Designs"?

A: This designation indicates that onsemi has discontinued active development and support for the SS12FP. New designs should utilize active alternatives such as the SS1P3LHM3/84A to ensure long-term availability, manufacturer support, and continued compliance with evolving standards.

Q: What are the package considerations when switching from SOD-123H to DO-220AA?

A: SOD-123H is a small outline surface mount package, while DO-220AA (SMP) is a larger surface mount package. The DO-220AA provides larger lead geometry and improved thermal dissipation. PCB footprint, trace routing, and thermal management design must be re-evaluated. Component placement density may be affected due to increased package size.

Q: Are there differences in reverse leakage current between the two parts?

A: The SS1P3LHM3/84A exhibits lower reverse leakage (200 µA @ 30 V) compared to the SS12FP (400 µA @ 20 V). Lower leakage current can improve circuit efficiency and reduce power dissipation in applications sensitive to standby current consumption.

Q: Do both parts have identical moisture sensitivity requirements?

A: Yes. Both the SS12FP and SS1P3LHM3/84A are rated MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. Standard handling and storage procedures apply without special desiccant or humidity control requirements.