IRLR7843PBF N-Channel MOSFET 30V 161A Equivalent & Substitute Parts

Part Overview

The IRLR7843PBF is an N-Channel MOSFET manufactured by Infineon Technologies, designed for high-current switching applications in the 30V class. This device features a continuous drain current rating of 161A at 25°C and is housed in a Surface Mount TO-252AA (DPAK) package. The part is classified as Discontinued at DiGi Electronics, making identification of functionally equivalent alternatives essential for ongoing design support and procurement planning. The HEXFET® series positioning indicates this device was engineered for demanding power conversion and motor control applications requiring low on-resistance and high current handling capability.

Substiute Parts

IRLR7843PBF

Infineon TechnologiesIn Stock: 1524IRLR7843PBF Datasheet

Current PartRFQ

STD100N3LF3

STMicroelectronicsIn Stock: 15489STD100N3LF3 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the IRLR7843PBF is determined by strict alignment of the following electrical and mechanical parameters:

Primary Substitution Criteria:

• Drain to Source Voltage (Vdss): Must equal 30V
• FET Type: Must be N-Channel
• Technology: Must be MOSFET (Metal Oxide)
• Package Type: Must be TO-252-3 DPAK or equivalent Surface Mount DPAK
• Operating Temperature Range: Must support -55°C to 175°C minimum
• RoHS Compliance: Must maintain ROHS3 Compliant status

Secondary Compatibility Parameters:

• Continuous Drain Current (Id): Substitute must meet or exceed 161A at 25°C for direct replacement
• Rds On (Max): Lower or equal values indicate improved performance
• Power Dissipation: Must support minimum 140W at Tc
• Gate Charge and Input Capacitance: Affect switching speed and drive circuit requirements

The STD100N3LF3 from STMicroelectronics meets the primary electrical voltage class (30V N-Channel MOSFET) and package requirements (DPAK Surface Mount). However, the continuous drain current rating of 80A is below the 161A specification of the IRLR7843PBF, classifying this as a downrated substitute suitable only for applications where current requirements do not exceed 80A.

Parameter Comparison

Engineering Selection Recommendations

Direct Replacement Availability: The IRLR7843PBF is listed as Discontinued at DiGi Electronics. The STD100N3LF3 is classified as Obsolete, indicating both devices have reached end-of-life status. Neither part is recommended for new design implementations.

Substitution Constraints: The STD100N3LF3 exhibits a 50% reduction in continuous drain current (80A versus 161A). This substitution is valid only for applications where:

• Maximum continuous drain current requirement does not exceed 80A
• Thermal management can accommodate the higher Rds On value (5.5mOhm versus 3.3mOhm)
• Power dissipation budget does not exceed 110W

Compliance Alignment: Both devices maintain ROHS3 Compliant status and identical operating temperature ranges (-55°C to 175°C). Package compatibility is confirmed for both TO-252-3 DPAK configurations, enabling mechanical interchangeability in PCB layouts.

Procurement Status: The STD100N3LF3 shows significantly higher inventory availability (15,465 Pcs) compared to the IRLR7843PBF (1,431 Pcs), though both are classified as discontinued or obsolete. For applications requiring the full 161A current rating, alternative 30V N-Channel MOSFETs from current product lines must be evaluated.

Frequently Asked Questions (FAQ)

Q: Can the STD100N3LF3 directly replace the IRLR7843PBF in all applications?

A: No. The STD100N3LF3 has a continuous drain current rating of 80A, which is 50% lower than the IRLR7843PBF's 161A rating. Direct replacement is limited to applications where maximum continuous drain current does not exceed 80A. For applications requiring the full 161A capability, alternative parts must be selected.

Q: What are the key electrical differences between these two devices?

A: The primary differences are continuous drain current (161A versus 80A), Rds On at rated conditions (3.3mOhm versus 5.5mOhm), power dissipation capability (140W versus 110W), and gate charge (50nC versus 27nC). The STD100N3LF3 exhibits lower input capacitance (2060pF versus 4380pF), which may result in faster switching characteristics in certain drive circuits.

Q: Are both devices available for new procurement?

A: Both the IRLR7843PBF and STD100N3LF3 are classified as discontinued or obsolete. The STD100N3LF3 shows higher current inventory levels (15,465 Pcs), but neither device is recommended for new design implementations. Current-generation 30V N-Channel MOSFETs should be evaluated for new projects.

Q: Do these devices share the same package footprint?

A: Yes. Both devices use the TO-252-3 DPAK (2 Leads + Tab) package configuration, also designated as SC-63. PCB layouts designed for the IRLR7843PBF are mechanically compatible with the STD100N3LF3 without modification.

Q: What compliance certifications apply to both devices?

A: Both devices are ROHS3 Compliant, REACH Unaffected, and classified under ECCN EAR99. Moisture Sensitivity Level (MSL) is rated as 1 (Unlimited) for both parts, indicating no moisture sensitivity restrictions during storage or handling.

Q: How do the gate charge specifications affect circuit design?

A: The IRLR7843PBF requires 50nC gate charge at 4.5V, while the STD100N3LF3 requires 27nC at 5V. Lower gate charge in the substitute part reduces drive circuit power dissipation and enables faster switching transitions. However, the higher input capacitance of the IRLR7843PBF (4380pF) may require different gate drive impedance matching compared to the STD100N3LF3 (2060pF).

Q: What thermal considerations apply when substituting these devices?

A: The IRLR7843PBF supports 140W maximum power dissipation, while the STD100N3LF3 is rated for 110W. The higher Rds On of the substitute (5.5mOhm versus 3.3mOhm) generates additional heat at equivalent current levels. Thermal management design must account for this 67% increase in on-resistance and reduced power dissipation headroom.