NXP Semiconductors BUK7908-40AIE127

Overview

BUK7908-40AIE from Nexperia is a standard-level N-channel TrenchPLUS MOSFET with integrated current sensing and ESD protection diodes, designed for automotive-critical systems. It features 40 V drain-source voltage rating, 6 mΩ typical R_DS(on) at 10 V_GS, 500:1 drain-to-sense current ratio, and AEC-Q101 qualification - enabling precise high-current monitoring in electric power steering (EPAS) actuators.

For engineers reviewing the BUK7908-40AIE datasheet, BUK7908-40AIE pinout, BUK7908-40AIE application, or BUK7908-40AIE equivalent, this device supports standard gate drive compatibility, Kelvin source sensing for low-noise current feedback, and TO-220 thermal performance up to 221 W at T_mb = 25 °C - critical for automotive motor control reliability validation.

Technical Context

This MOSFET uses TrenchMOS technology with dedicated ISENSE and Kelvin source (KS) terminals to isolate sense path inductance and enable accurate real-time current measurement. Its gate threshold voltage (2–4 V at 25 °C) and low 78 nC total gate charge support fast switching with standard 10 V logic-level drivers.

The device integrates ESD protection diodes and meets AEC-Q101 requirements for automotive use, with avalanche energy rating of 0.63 J (unclamped) and junction temperature range from –55 °C to +175 °C - ensuring robustness under transient overloads and extreme thermal cycling.

Key Specifications

Pinout & Package

Package: TO-220 (SOT263B), plastic single-ended package with heatsink-mounted mounting base and 5 leads.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel automotive MOSFET applications.

Compared with STL220N4F7AG and IPP040N04L, the BUK7908-40AIE uniquely combines AEC-Q101 qualification, integrated current sensing with Kelvin source, and 6 mΩ on-resistance in a single TO-220 footprint - delivering functional safety-ready motor control with minimal BOM overhead.

Availability

BUK7908-40AIE is available at Aetrix Electronics and suitable for electrical power assisted steering (EPAS), variable valve timing (VVT), brake-by-wire actuation, electric turbocharger control, and automotive body control modules requiring stable component supply and long-term automotive lifecycle support.

Supply support for BUK7908-40AIE includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Nexperia is a global semiconductor expert specializing in high-volume, high-reliability discrete and logic devices, with leadership in automotive-grade MOSFETs and ESD-protected components.

The BUK7908-40AIE belongs to Nexperia's TrenchPLUS automotive MOSFET family, engineered specifically for high-current, safety-critical motor control applications where integrated sensing, thermal robustness, and AEC-Q101 compliance are mandatory.

FAQ

What is the maximum continuous drain current rating for BUK7908-40AIE at 100 °C mounting base temperature?

The BUK7908-40AIE supports 75 A continuous drain current at T_mb = 100 °C, limited by package thermal constraints rather than silicon capability. This value is confirmed in Table 4 (Limiting values) of the official Nexperia datasheet Rev. 03. At lower temperatures, the rating increases to 117 A at T_mb = 25 °C. The BUK7908-40AIE must be mounted to an adequately sized heatsink to sustain rated current without exceeding 175 °C junction temperature.

Does BUK7908-40AIE require a negative gate voltage for reliable turn-off in automotive applications?

No, the BUK7908-40AIE does not require negative gate drive. Its gate-source voltage range is specified from –20 V to +20 V, but it achieves full enhancement at V_GS = 10 V and maintains stable off-state with V_GS = 0 V. The BUK7908-40AIE gate threshold voltage is 2–4 V at 25 °C, making it compatible with standard 12 V automotive supply rails and eliminating need for gate driver charge pumps or negative bias circuits.

How is the current sense ratio (ID/Isense) of BUK7908-40AIE affected by temperature?

The ID/Isense ratio of the BUK7908-40AIE remains tightly controlled across temperature, with a guaranteed range of 450–550 over T_j = –55 °C to +175 °C. Figure 15 in the datasheet shows minimal drift versus V_GS, and Table 6 confirms the ratio is specified under all operating junction temperatures - ensuring consistent current feedback accuracy without software compensation in the BUK7908-40AIE-based design.

Can BUK7908-40AIE be used in parallel configurations for higher current handling?

Yes, the BUK7908-40AIE supports paralleling due to its positive temperature coefficient of R_DS(on), which promotes current sharing. However, individual gate resistors and matched PCB trace lengths are required to ensure balanced dynamic switching. The BUK7908-40AIE's low 78 nC gate charge and 34 nC gate-drain charge simplify gate driver design for multi-device configurations in high-power EPAS inverters.

What is the thermal resistance from junction to mounting base (Rth(j-mb)) for BUK7908-40AIE?

The maximum thermal resistance from junction to mounting base (R_th(j-mb)) for the BUK7908-40AIE is 0.68 K/W, as specified in Table 5 of the Nexperia datasheet. This value assumes proper mechanical mounting with thermal interface material and adequate heatsink mass. The BUK7908-40AIE's low R_th(j-mb) enables efficient heat transfer directly from the die to the chassis, supporting high-power density designs in space-constrained automotive modules.