Nexperia USA Inc. PMBT5550,215

Overview

PMBT5550 from Nexperia is an NPN high-voltage transistor in SOT23 package, rated for 140 V V_CEO, 300 mA I_C, and AEC-Q101 qualified for automotive use. It serves as a general-purpose switching element in low-current, high-voltage DC circuits such as LED drivers, relay drivers, and sensor interface stages.

For engineers reviewing the PMBT5550 datasheet, PMBT5550 pinout, PMBT5550 application, or PMBT5550 equivalent, key selection criteria include its 140 V collector-emitter breakdown voltage, 250 mW power dissipation at 25 °C ambient, AEC-Q101 qualification, and SOT23 footprint compatibility with space-constrained PCB layouts.

Technical Context

This discrete NPN bipolar junction transistor operates in active or saturation mode with DC current gain (h_FE) ranging from 20 to 250 depending on collector current-60 at I_C = 1 mA, 250 at I_C = 10 mA-and supports fast switching via 100–300 MHz transition frequency (f_T). Its low leakage (ICBO ≤ 50 nA at 25 °C, ≤ 50 µA at 100 °C) ensures stable biasing in temperature-variable environments.

The device adheres to IEC 60134 absolute maximum ratings, with V_CBO = 160 V, V_EBO = 6 V, and thermal resistance R_th(j-a) = 500 K/W on FR4 PCB. It is not a logic-level or RF power device but optimized for robust, cost-effective medium-voltage switching where precision linearity or RF performance is not required.

Key Specifications

Pinout & Package

SOT23 (TO-236AB) plastic surface-mount package: 3-terminal, 1.9 mm pitch, 2.9 mm × 1.3 mm × 1.0 mm body, tin-plated copper leads, FR4-compatible footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN high-voltage switching applications.

Compared with BC847B,215, PMBT5550 provides triple the voltage rating and three times the current capacity; versus MMBT5551, it trades 20 V V_CEO margin and 300 mA I_C headroom for tighter gain consistency and lower cost in moderate-duty automotive switching.

Availability

PMBT5550 is available at Aetrix Electronics and suitable for automotive interior lighting, industrial sensor interfaces, power supply enable control, and electromechanical relay driver applications requiring stable component supply and AEC-Q101 compliance.

Supply support for PMBT5550 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 high-volume, high-reliability discrete and logic devices, with roots in Philips Semiconductors and headquartered in Nijmegen, Netherlands.

The PMBT5550 belongs to Nexperia's AEC-Q101-qualified general-purpose transistor portfolio, designed specifically for cost-sensitive, medium-voltage automotive and industrial switching where robustness and manufacturability outweigh ultra-high-speed or RF requirements.

FAQ

Is PMBT5550 suitable for high-frequency switching above 1 MHz?

Yes, with design constraints: its f_T of 100–300 MHz supports switching up to ~10 MHz, but practical operation above 1 MHz requires careful layout to minimize parasitic inductance and capacitance. V_CE(sat) increases with frequency due to minority-carrier storage time, so gate/base drive strength and snubber design must be validated per application.

What is the maximum allowable base current for continuous operation?

The absolute maximum peak base current is 100 mA (single pulse, t_p ≤ 1 ms), but for continuous DC operation, I_B must be limited to maintain T_j ≤ 150 °C. At I_C = 300 mA and h_FE = 60, required I_B ≈ 5 mA; derating to ≤ 2 mA ensures long-term reliability on standard FR4 with no added copper.

Does PMBT5550 require a flyback diode when driving inductive loads?

Yes-when switching relay coils or solenoids, a reverse-biased flyback diode (e.g., 1N4148) must be placed across the load to clamp V_CE spikes. Although V_CEO is rated at 140 V, unclamped inductive kick can exceed this, causing avalanche stress and accelerated degradation even below absolute maximum limits.

Can PMBT5550 replace BC547 in existing designs?

Only with verification: while both are NPN SOT23 transistors, PMBT5550 has higher V_CEO (140 V vs. 45 V) and lower h_FE minimum (20 vs. 110), which may cause insufficient gain or unintended saturation in BC547-based bias networks. Layout and thermal validation are mandatory before substitution.