Diodes Incorporated DXT5551-13

Overview

DXT5551-13 from Diodes Incorporated is a 160V NPN high-voltage transistor in SOT89 package, rated for 600mA collector current and 0.75W power dissipation at 25°C ambient on minimum pad layout. It features BV_CEO = 160V, V_CE(sat) ≤ 0.20V at I_C = 50mA/I_B = 5mA, and f_T up to 300MHz - enabling use in medium-power switching and linear amplification stages of industrial power supplies and LED drivers.

For engineers reviewing the DXT5551-13 datasheet, DXT5551-13 pinout, DXT5551-13 application, or DXT5551-13 equivalent, key selection criteria include its 160V V_CEO rating, SOT89 thermal performance (R_θJA = 166°C/W), complementary pairing with DXT5401, and suitability for non-automotive industrial switching where lead-free, halogen-free compliance is required.

Technical Context

The DXT5551-13 is a silicon NPN bipolar junction transistor optimized for medium-power linear and switching operation. Its high BV_CEO (160V) and robust SOA support stable operation under inductive load switching, while its h_FE range (80–250 at I_C = 10mA) enables predictable DC biasing in amplifier configurations.

Thermal design leverages the SOT89 exposed collector pad: R_θJA improves from 166°C/W (min pad) to 104°C/W (25mm × 25mm copper), and ESD ratings meet JEDEC Class 3A HBM (4kV), supporting reliable handling in production environments without special static control beyond standard practices.

Key Specifications

Pinout & Package

Package: SOT89 - surface-mount plastic package with exposed collector pad for thermal enhancement; dimensions per Diodes outline SOT89 (D = 4.50 mm, E = 2.50 mm, H = 4.10 mm); RoHS-compliant, halogen-free molding compound (UL 94V-0).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJD127G and ZTX653, the DXT5551-13 uniquely balances 160V rating, SOT89 thermal efficiency, and full RoHS 3/halogen-free compliance - making it optimal for space-constrained, environmentally regulated industrial power interfaces where voltage margin and regulatory alignment are both critical.

Availability

DXT5551-13 is available at Aetrix Electronics and suitable for industrial power supplies, LED drivers, and relay interface circuits requiring stable component supply, long-term manufacturability, and full environmental compliance.

Supply support for DXT5551-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The DXT5551 belongs to Diodes' high-voltage bipolar transistor product line, engineered specifically for industrial and commercial power management applications demanding reliability, thermal efficiency, and regulatory compliance without automotive qualification overhead.

FAQ

Is DXT5551-13 qualified to AEC-Q101 for automotive use?

No. The DXT5551-13 is not AEC-Q101 qualified. Diodes explicitly states that automotive-grade versions require specific change control, PPAP capability, and IATF 16949 manufacturing - none of which apply to this part. It is intended for industrial, commercial, and consumer applications only.

What is the maximum continuous power dissipation at 70°C ambient?

Using the derating curve (Figure 2), max power drops linearly from 0.75W at 25°C to 0W at 125°C. At 70°C ambient, allowable power is 0.75W × (1 − (70−25)/(125−25)) = 0.3375W. This assumes mounting on minimum recommended pad layout per datasheet Note 5.

Can DXT5551-13 replace BC817-40 in a 5V logic interface?

No - BC817-40 is a general-purpose 45V/500mA transistor optimized for low-voltage digital switching. DXT5551-13's higher V_CEO, higher V_CE(sat), and different h_FE profile make it over-specified and less efficient in 5V logic-level applications; its design intent is medium-voltage power switching, not signal-level amplification.

Does the SOT89 package require solder paste stencil adjustments for the exposed collector pad?

Yes. Diodes recommends a solder paste stencil aperture covering 50–70% of the exposed collector pad area to prevent voiding and tombstoning. The datasheet references "minimum recommended pad layout" - detailed in Diodes' SOT89 packaging guide - which specifies thermal pad dimensions and solder mask clearance to ensure mechanical stability and thermal performance.