Nexperia USA Inc. PUMD4-QX

Overview

PUMD4-QX from Nexperia is a resistor-equipped double transistor (RET) in SOT363 package, integrating one NPN and one PNP silicon transistor with built-in 10 kΩ input bias resistors (R1) and open R2 terminals. It supports 50 V V_CEO, 100 mA output current per transistor, and operates across −65 °C to +150 °C ambient range. Used for low-current peripheral driving and IC input control in automotive body electronics.

For engineers reviewing the PUMD4-QX datasheet, PUMD4-QX pinout, PUMD4-QX application, or PUMD4-QX equivalent, this page delivers verified electrical parameters, AEC-Q101 qualification status, thermal derating curves, SOT363 footprint details, and validated automotive-grade alternatives - all aligned with Nexperia's official 2022 product data sheet.

Technical Context

The PUMD4-QX implements a dual-transistor topology with independent NPN (TR1) and PNP (TR2) elements sharing no internal connection between collectors or emitters. Each transistor includes a dedicated 10 kΩ base-input resistor (R1), while R2 is unconnected - enabling direct logic-level drive without external bias networks.

Its operation is defined by discrete DC gain (h_FE ≥ 200 at I_C = 1 mA), low V_CEsat ≤ 150 mV at I_C = 10 mA/I_B = 0.5 mA, and junction-to-ambient thermal resistance of 416 K/W (per device on FR4 PCB), supporting stable performance in space-constrained automotive modules.

Key Specifications

Pinout & Package

SOT363 (TSSOP6) plastic surface-mounted package with 0.65 mm lead pitch, 2.1 mm × 1.25 mm body, and gull-wing leads suitable for reflow and wave soldering per Figures 6–7.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar resistor-equipped transistor applications.

Compared with PUMH4 and PUMB4, the PUMD4-QX uniquely supports mixed-polarity drive within one package - enabling compact push-pull stages, bidirectional level shifting, and reduced interconnect complexity in automotive body control units.

Availability

PUMD4-QX is available at Aetrix Electronics and suitable for automotive door modules, industrial sensor interfaces, USB-C power switches, and smart home actuator control requiring stable component supply and AEC-Q101 compliance.

Supply support for PUMD4-QX 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 efficiency technologies, delivering high-performance logic, discrete, and MOSFET devices optimized for automotive, industrial, and consumer applications.

The PUMD4-QX belongs to Nexperia's Resistor-Equipped Transistor (RET) product line, engineered to replace general-purpose transistors in digital logic interfacing and low-power switching - reducing design complexity and board space in automotive ECUs and IoT edge nodes.

FAQ

What is the function of R2 in the PUMD4-QX?

R2 is open (unconnected) in the PUMD4-QX, as confirmed in Table 8 and Section 11 of the datasheet. This configuration allows direct base drive through R1 alone, eliminating the need for secondary biasing networks. No internal connection exists between R2 and any transistor terminal - it is not a floating node but a non-existent terminal in this variant.

Can PUMD4-QX replace discrete BC847/BC857 pairs?

Yes - the PUMD4-QX replaces one BC847 (NPN) and one BC857 (PNP) plus their four external 10 kΩ base resistors. Its matched h_FE ≥ 200, 50 V V_CEO, and 100 mA I_O meet or exceed BC847/BC857 specifications, while the integrated R1 resistors ensure consistent biasing without layout-dependent variations.

Is thermal performance specified per transistor or per device?

Thermal resistance is specified both ways: R_th(j-a) = 625 K/W per transistor (free air), and 416 K/W per device on FR4 PCB (single-sided copper). The lower per-device value reflects shared heat dissipation across both transistors in the SOT363 package - critical for calculating total power limits in real PCB layouts.

Does PUMD4-QX support 3.3 V MCU GPIO direct drive?

Yes - with R1 = 10 kΩ, a 3.3 V GPIO delivers ~330 µA base current to each transistor (I_B ≈ (3.3 V − 0.7 V)/10 kΩ), sufficient to saturate both TR1 and TR2 at up to 66 mA output (h_FE ≥ 200). This enables reliable switching without additional level-shifting circuitry.