Diodes Incorporated ZXTN08400BFFTA

Overview

ZXTN08400BFF from Diodes Incorporated is a 400 V NPN medium-power high-voltage transistor in SOT23F package, designed for forward-blocking applications requiring >450 V collector-base and collector-emitter breakdown voltage, 0.5 A continuous collector current, and low 175 mV saturation voltage at 500 mA. It serves as a high-voltage switching element in compact power supplies and industrial control circuits.

For engineers reviewing the ZXTN08400BFF datasheet, ZXTN08400BFF pinout, ZXTN08400BFF application, or ZXTN08400BFF equivalent, key selection criteria include its AEC-Q101 qualification, 1.5 W power dissipation capability with thermal resistance as low as 60 °C/W on 50 mm × 50 mm 2 oz copper, and complementary PNP pairing with ZXTP08400BFF.

Technical Context

This NPN bipolar junction transistor operates in linear and switching modes with verified forward-blocking capability up to 450 V (BV_CEX) and 400 V (BV_CEO). Its low V_CE(SAT) of 70–175 mV across 20–500 mA collector currents enables efficient high-voltage switching with minimal conduction loss.

The device features a thermally enhanced SOT23F package with exposed collector pad, delivering R_θJA = 60 °C/W under optimized PCB layout (50 mm × 50 mm, 2 oz Cu), and supports operation from –55 °C to +150 °C with 4 kV HBM ESD rating per JEDEC Class 3A.

Key Specifications

Pinout & Package

SOT23F is a surface-mount, low-profile variant of SOT23 with an exposed collector pad for enhanced thermal performance. It maintains pin compatibility with standard SOT23 footprints while enabling higher power dissipation in space-constrained layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTN08400BFF, ZXTN2012E6TA trades voltage capability for current and cost, while MJD127G sacrifices miniaturization and high-voltage tolerance for raw power-handling and thermal mass - neither matches the unique combination of 400 V blocking, SOT23F form factor, and AEC-Q101 compliance.

Availability

ZXTN08400BFF is available at Aetrix Electronics and suitable for industrial power supplies, automotive lighting control, and solenoid driver modules requiring stable component supply, AEC-Q101 qualification, and RoHS-compliant green packaging.

Supply support for ZXTN08400BFF 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, specializing in high-reliability, application-optimized components for automotive, industrial, and consumer markets.

ZXTN08400BFF belongs to Diodes' high-voltage bipolar transistor product line, engineered specifically for compact, high-efficiency switching in space- and thermal-constrained environments where traditional TO-92 or SOT89 devices cannot fit.

FAQ

What is the maximum safe operating voltage for ZXTN08400BFF in continuous DC blocking?

The absolute maximum collector-emitter voltage (V_CEO) is rated at 400 V, and the forward-blocking voltage (V_CEX) is guaranteed ≥450 V with base-emitter resistor ≤1 kΩ or V_BE between –1 V and +0.25 V. For reliable long-term operation, design margins should limit steady-state DC blocking to ≤360 V per datasheet leakage test conditions.

Can ZXTN08400BFF be used in avalanche mode?

No - ZXTN08400BFF is not rated or characterized for controlled avalanche operation. Its BV_CEX and BV_CEO specifications define safe non-destructive breakdown limits under pulsed test conditions, but the device lacks avalanche energy rating (E_AS) or ruggedness validation required for intentional avalanche use.

How does the SOT23F package improve thermal performance over standard SOT23?

SOT23F incorporates an exposed collector pad that provides direct thermal conduction to the PCB copper plane. When mounted on 50 mm × 50 mm, 2 oz copper, its R_θJA drops to 60 °C/W - a 33% improvement over standard SOT23 (typically ~90 °C/W) - enabling 1.5 W power dissipation without external heatsinking.

Is ZXTN08400BFF pin-compatible with standard SOT23 footprints?

Yes - SOT23F uses identical 1.9 mm × 2.4 mm body dimensions and 0.95 mm lead pitch as industry-standard SOT23, allowing drop-in replacement on existing layouts. However, the exposed collector pad requires matching copper land pattern per Diodes' recommended pad layout to achieve rated thermal performance.