Nexperia USA Inc. PMBT3904M,315

Overview

PMBT3904M from Nexperia is an AEC-Q101-qualified NPN general-purpose switching transistor in a leadless DFN1006-3 (SOT883) package, rated for 40 V V_CEO, 200 mA I_C, and DC current gain (h_FE) of 100–300 at I_C = 10 mA. It delivers fast switching performance with t_on ≤ 70 ns and t_off ≤ 250 ns, and is widely used in automotive body electronics for discrete load switching.

For engineers reviewing the PMBT3904M datasheet, PMBT3904M pinout, PMBT3904M application, or PMBT3904M equivalent, key selection criteria include its ultra-small 1.0 mm × 0.6 mm footprint, AEC-Q101 qualification, guaranteed h_FE range, V_CE(sat) ≤ 300 mV at I_C/I_B = 10, and thermal resistance R_th(j-a) = 212 K/W on FR4 with 1 cm² collector pad.

Technical Context

This NPN bipolar junction transistor operates as a single-stage switch or small-signal amplifier with open-base V_CEO = 40 V and V_CB0 = 60 V, supporting reliable operation across −55 °C to +150 °C ambient. Its h_FE remains stable over temperature (−55 °C to +150 °C), and V_BE(sat) is specified at 850–950 mV under I_C = 50 mA / I_B = 5 mA conditions.

The device uses reflow soldering only and is mounted on FR4 PCBs with defined thermal pad layouts. Its transient thermal impedance Z_th(j-a) drops to ~212 K/W at steady state when using a 1 cm² collector mounting pad, enabling sustained 200 mA operation within thermal limits.

Key Specifications

Pinout & Package

DFN1006-3 (SOT883) is a 3-terminal, leadless, ultra-small surface-mount plastic package measuring 1.02 mm × 0.62 mm × 0.48 mm with 0.35 mm pitch. It features a transparent top view and requires reflow soldering only.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN switching transistor applications.

Compared with BC846BW,115, PMBT3904M offers automotive qualification and 60% smaller footprint but lower V_CEO; compared with PMBT3904,315, it retains identical functionality while reducing PCB area by 85%, at the cost of tighter thermal management requirements.

Availability

PMBT3904M is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, USB-C power path control, and compact LED driver circuits requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for PMBT3904M 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 focused on essential semiconductors, delivering high-performance, reliable components for automotive, industrial, and consumer markets.

The PMBT3904M belongs to Nexperia's AEC-Q101-qualified discrete transistor portfolio, engineered specifically for space-constrained, thermally demanding automotive subsystems requiring robust switching performance and long-term reliability.

FAQ

Is PMBT3904M suitable for linear amplification applications?

Yes - its h_FE stability across temperature and low noise figure (NF = 5 dB at 100 µA) support small-signal amplification in sensor front-ends. However, it is optimized for switching: V_CE(sat) and t_off are fully characterized, while linearity parameters like distortion or bandwidth beyond f_T = 300 MHz are not specified.

What is the recommended PCB layout for thermal performance?

Use a minimum 1 cm² copper pour connected to Pin 3 (collector) on the top layer, with ≥4 thermal vias (0.3 mm diameter) to inner ground planes. Maintain standard SOT883 reflow footprint per Figure 10 - including 0.4 mm solder lands and 0.7 mm overall pad length - to ensure mechanical reliability and thermal transfer.

Can PMBT3904M replace BC817-40 in existing designs?

No - BC817-40 uses SOT23 packaging and has different pinout (E-B-C vs. B-E-C), higher I_C = 500 mA, and no AEC-Q101 rating. Direct replacement would require PCB redesign, revised base drive calculations due to differing h_FE distribution, and revalidation for automotive use cases.

Does PMBT3904M support bidirectional current flow?

No - it is a unidirectional NPN bipolar transistor. Collector and emitter are not interchangeable: reverse biasing V_EC exceeds VEBO = 6 V and risks junction breakdown. For bidirectional switching, a complementary pair (e.g., PMBT3904M + PMBT3906M) or dedicated analog switch IC is required.