SD2931 RF MOSFET 50V Equivalent & Substitute Parts

Part Overview

The SD2931 is an N-Channel RF MOSFET manufactured by STMicroelectronics, rated for 50V operation with 150W output power at 175MHz frequency. This component is classified as obsolete, which necessitates identification of equivalent and substitute parts for ongoing design requirements and procurement needs. Active alternatives with comparable electrical and mechanical specifications are available from both STMicroelectronics and alternative manufacturers.

Substiute Parts

SD2931

STMicroelectronicsIn Stock: 890SD2931 Datasheet

Current PartRFQ

SD2931-11W

STMicroelectronicsIn Stock: 2317SD2931-11W Datasheet

DirectRFQ

MRF171A

MACOM Technology SolutionsIn Stock: 1327MRF171A Datasheet

SimilarRFQ

MRF174

MACOM Technology SolutionsIn Stock: 2239MRF174 Datasheet

SimilarRFQ

VRF150

Microchip TechnologyIn Stock: 33324VRF150 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SD2931 is determined by alignment across the following critical parameters: voltage rating (test and rated), output power capability, frequency range, current handling capacity, package type, and compliance certifications. Substitute parts are grouped into two categories based on substitution relationship type.

Direct Equivalent Category: Parts that maintain identical or near-identical electrical specifications and package configuration, enabling direct replacement without circuit modification.

Similar Specification Category: Parts that provide comparable functional performance within the RF MOSFET application space but may differ in specific electrical parameters such as frequency range, gain, or current rating. These parts require application-level verification of suitability.

The following parameters form the basis for substitution eligibility:

• Voltage - Test: 50V (primary criterion)
• Voltage - Rated: 125V or higher
• Power - Output: 150W (primary criterion)
• Frequency: 175MHz or overlapping range
• Package / Case: M244 or compatible RF package
• Configuration: N-Channel
• RoHS3 Compliance

Parameter Comparison

Engineering Selection Recommendations

SD2931-11W (Direct Equivalent - Recommended Primary Substitute)

The SD2931-11W is the preferred direct replacement for the obsolete SD2931. Both parts are manufactured by STMicroelectronics and share identical electrical specifications: 50V test voltage, 125V rated voltage, 20A current rating, 175MHz frequency, 15dB gain, and 150W output power. The SD2931-11W maintains the same M244 package configuration. The primary distinction is product status: SD2931-11W is active with unlimited MSL rating (1), compared to the obsolete SD2931 with MSL-3 rating. This part is available in high inventory (2264 units) and requires no circuit modification for implementation.

VRF150 (Similar Specification - Alternative Option)

The VRF150 from Microchip Technology provides equivalent electrical performance in critical parameters: 50V test voltage, 150W output power, and 250mA test current. Frequency specification is 150MHz, which is 25MHz lower than the SD2931. Gain is specified at 11dB compared to 15dB for the SD2931. The VRF150 uses the M174 package rather than M244, requiring PCB layout evaluation. Rated voltage is 170V, exceeding the SD2931 specification. This part is active with unlimited MSL rating and available in high inventory (33300 units).

MRF174 (Similar Specification - Lower Power Alternative)

The MRF174 from MACOM Technology Solutions operates at 28V test voltage and 65V rated voltage, representing a significant reduction from the SD2931 specifications. Output power is 125W compared to 150W. Frequency is 150MHz with 11.8dB gain. Current rating is 13A. The MRF174 uses package 211-11 and is active with unlimited MSL rating. This part is suitable only for applications where lower voltage operation is acceptable.

MRF171A (Similar Specification - Lower Power Alternative)

The MRF171A from MACOM Technology Solutions operates at 28V test voltage and 65V rated voltage. Output power is 45W, substantially lower than the SD2931. Frequency range is 30MHz to 200MHz, providing broader frequency coverage. Gain is 19.5dB. Current rating is 4.5A. The MRF171A uses package 211-07 and is active with unlimited MSL rating. This part is suitable only for lower-power applications.

All substitute parts maintain ROHS3 compliance and EAR99 export classification consistent with the original SD2931.

Frequently Asked Questions (FAQ)

Q: Can the SD2931-11W be used as a direct replacement for the SD2931?

A: Yes. The SD2931-11W is a direct equivalent with identical electrical specifications and package configuration. No circuit modification is required. The primary difference is that SD2931-11W is an active product with improved moisture sensitivity rating (MSL-1 versus MSL-3).

Q: What is the key difference between the SD2931 and VRF150?

A: Both parts operate at 50V test voltage and deliver 150W output power. The VRF150 operates at 150MHz frequency compared to 175MHz for the SD2931, and provides 11dB gain versus 15dB. The VRF150 uses M174 package instead of M244. The VRF150 is suitable for applications where the lower frequency and gain specifications are acceptable.

Q: Can MRF174 or MRF171A replace the SD2931 in all applications?

A: No. Both MRF174 and MRF171A operate at 28V test voltage, which is significantly lower than the SD2931 specification of 50V. MRF174 delivers 125W output power (versus 150W), and MRF171A delivers only 45W. These parts are suitable only for applications designed for lower voltage and power operation.

Q: What package considerations apply to substitute parts?

A: The SD2931-11W maintains the M244 package, enabling direct PCB compatibility. The VRF150 uses M174 package, requiring PCB layout evaluation. The MRF174 and MRF171A use packages 211-11 and 211-07 respectively, both requiring significant PCB redesign. Package selection depends on existing circuit board design constraints.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All substitute parts listed (SD2931-11W, VRF150, MRF174, and MRF171A) are ROHS3 compliant, maintaining environmental compliance consistency with the original SD2931.

Q: What is the inventory status of substitute parts?

A: SD2931-11W has 2264 units in stock. VRF150 has 33300 units in stock. MRF174 has 2200 units in stock. MRF171A has 1296 units in stock. All parts are available as new original components.

Q: How does moisture sensitivity rating affect part selection?

A: The SD2931 has MSL-3 rating (168-hour limit), while all substitute parts have MSL-1 rating (unlimited). MSL-1 parts provide superior moisture tolerance and longer shelf life without baking requirements, making them preferable for long-term storage and supply chain management.