FDMS7658AS N-Channel MOSFET 30V 29A/70A Equivalent & Substitute Parts

Part Overview

The FDMS7658AS is an N-Channel MOSFET manufactured by onsemi, rated for 30V drain-to-source voltage with continuous drain current of 29A at Ta and 70A at Tc. This device is housed in an 8-PQFN (5x6) surface mount package and is part of the PowerTrench® and SyncFET™ series. The FDMS7658AS is currently classified as obsolete, making identification of equivalent and substitute parts necessary for ongoing design support, production continuity, and component sourcing.

Substiute Parts

FDMS7658AS

onsemiIn Stock: 30626FDMS7658AS Datasheet

Current PartRFQ

CSD17576Q5B

Texas InstrumentsIn Stock: 9596CSD17576Q5B Datasheet

SimilarRFQ

CSD17576Q5BT

Texas InstrumentsIn Stock: 1317CSD17576Q5BT Datasheet

SimilarRFQ

RJK0346DPA-01#J0B

Renesas Electronics CorporationIn Stock: 3413RJK0346DPA-01#J0B Datasheet

SimilarRFQ

RS1E280BNTB

Rohm SemiconductorIn Stock: 35757RS1E280BNTB Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FDMS7658AS is determined by strict alignment of the following electrical and mechanical parameters:

Critical Matching Parameters:

• Drain-to-Source Voltage (Vdss): Must equal or exceed 30V
• FET Type: N-Channel only
• Technology: MOSFET (Metal Oxide)
• Mounting Type: Surface Mount
• Operating Temperature Range: Must support -55°C to 150°C
• RoHS Compliance: ROHS3 Compliant
• MSL Rating: 1 (Unlimited)

Performance Parameters for Functional Equivalence:

• Continuous Drain Current: Substitute must meet or exceed 29A @ Ta
• RDS(on) @ 10V: Substitute performance should align with 1.9mOhm specification
• Gate Charge (Qg): Lower values indicate improved switching performance
• Input Capacitance (Ciss): Lower values reduce gate drive requirements

Package Considerations: The FDMS7658AS uses an 8-PQFN (5x6) package. Substitute parts may use alternative 8-pin surface mount packages (8-VSONP, 8-WPAK, 8-HSOP) provided the physical footprint and pin configuration support direct board-level substitution or minor PCB layout adjustment.

Parameter Comparison

Engineering Selection Recommendations

CSD17576Q5B and CSD17576Q5BT (Texas Instruments NexFET™)

Both CSD17576Q5B and CSD17576Q5BT are active-status N-Channel MOSFETs rated for 30V with 100A continuous drain current. These devices exceed the FDMS7658AS current rating and feature lower gate charge (68 nC and 32 nC respectively) and reduced input capacitance (4430 pF), resulting in improved switching performance. Both are ROHS3 compliant with MSL 1 rating. The primary difference is packaging: CSD17576Q5B is supplied in Cut Tape format, while CSD17576Q5BT is supplied in Tape & Reel format. The 8-VSONP (5x6) package differs from the original 8-PQFN but maintains equivalent footprint dimensions. These devices are suitable for applications requiring higher current capability and lower switching losses.

RJK0346DPA-01#J0B (Renesas Electronics)

The RJK0346DPA-01#J0B is an active-status N-Channel MOSFET rated for 30V with 65A continuous drain current. This device features the lowest RDS(on) specification at 1.8 mOhm @ 25A, 10V, and moderate gate charge of 49 nC @ 10V. The 8-WPAK package differs from the original 8-PQFN. This device is ROHS3 compliant with MSL 1 rating and is suitable for applications prioritizing low on-resistance and thermal performance.

RS1E280BNTB (Rohm Semiconductor)

The RS1E280BNTB is an active-status N-Channel MOSFET rated for 30V with 28A continuous drain current at Ta and 80A at Tc, closely matching the FDMS7658AS current specifications. This device features RDS(on) of 2.3 mOhm @ 28A, 10V and gate charge of 94 nC @ 10V. The 8-HSOP package differs from the original 8-PQFN. This device is ROHS3 compliant with MSL 1 rating and provides the closest electrical performance match to the original part.

All substitute parts maintain compliance with ROHS3 and REACH requirements, operate across the full -55°C to 150°C temperature range, and are currently in active production status.

Frequently Asked Questions (FAQ)

Q: Can the CSD17576Q5B or CSD17576Q5BT directly replace the FDMS7658AS without PCB modification?

A: The CSD17576Q5B and CSD17576Q5BT use the 8-VSONP (5x6) package, which differs from the original 8-PQFN (5x6) package. While both packages maintain 5x6mm footprint dimensions, pin configurations and solder pad layouts differ. PCB layout evaluation and potential footprint adjustment are required before substitution.

Q: What is the primary advantage of the CSD17576Q5BT over the CSD17576Q5B?

A: Both devices are electrically identical with 30V rating and 100A continuous drain current. The difference is packaging format: CSD17576Q5B is supplied in Cut Tape format, while CSD17576Q5BT is supplied in Tape & Reel format. Selection depends on procurement and assembly requirements.

Q: Why does the RS1E280BNTB have lower power dissipation at Tc (30W) compared to the FDMS7658AS (89W)?

A: Power dissipation specifications depend on thermal management design, package thermal resistance, and application-specific conditions. The RS1E280BNTB's lower Tc power rating reflects its specific package thermal characteristics. Actual thermal performance in a given application depends on PCB layout, thermal vias, and heat sinking implementation.

Q: Is the RJK0346DPA-01#J0B suitable for applications requiring the full 70A continuous current of the FDMS7658AS?

A: The RJK0346DPA-01#J0B is rated for 65A continuous drain current at Ta, which is below the 70A specification of the FDMS7658AS. This device is suitable for applications requiring up to 65A. For applications requiring the full 70A capability, the CSD17576Q5B or CSD17576Q5BT (100A rating) are more appropriate.

Q: Are all substitute parts RoHS3 compliant and suitable for regulated industries?

A: All substitute parts listed are ROHS3 compliant and REACH unaffected. All devices carry MSL 1 (Unlimited) moisture sensitivity rating. Compliance certifications match the original FDMS7658AS specifications.

Q: What is the impact of lower gate charge in the CSD17576Q5BT (32 nC @ 4.5V) compared to the FDMS7658AS (109 nC @ 10V)?

A: Lower gate charge reduces the energy required to switch the device and decreases gate drive circuit complexity. However, gate charge specifications are measured at different gate voltage conditions (4.5V vs. 10V), making direct comparison imprecise. Gate drive circuit design must account for the specific voltage and current requirements of each device.

Q: Can the RS1E280BNTB be used in high-frequency switching applications?

A: The RS1E280BNTB features gate charge of 94 nC @ 10V, which is comparable to the FDMS7658AS (109 nC @ 10V). Input capacitance is 5100 pF @ 15V. These parameters indicate moderate switching speed capability. Applications requiring very high switching frequencies may benefit from devices with lower gate charge, such as the CSD17576Q5BT (32 nC @ 4.5V).

Q: What packaging considerations apply when substituting the FDMS7658AS?

A: The FDMS7658AS uses 8-PQFN (5x6). Substitute parts use alternative 8-pin packages: CSD17576Q5B/CSD17576Q5BT use 8-VSONP (5x6), RJK0346DPA-01#J0B uses 8-WPAK, and RS1E280BNTB uses 8-HSOP. While footprint dimensions may be similar, pin assignments and solder pad geometries differ. PCB layout verification is required before substitution.