Diodes Incorporated ZXTP25140BFHTA

Overview

ZXTP25140BFHTA from Diodes Incorporated (formerly Zetex Semiconductors) is a PNP medium-power bipolar junction transistor in SOT23 package, rated for -140 V V_CEO, -1 A continuous collector current, 1.25 W power dissipation on 50 mm × 50 mm PCB, and -260 mV V_CE(sat) at -1 A / -100 mA drive-designed for high-side switching in DC-DC converters.

For engineers reviewing the ZXTP25140BFHTA datasheet, ZXTP25140BFHTA pinout, ZXTP25140BFHTA application, or ZXTP25140BFHTA equivalent, key selection criteria include verified -180 V forward blocking voltage, low saturation voltage under high-current switching, thermal resistance of 100 °C/W on standard FR4 layout, and SOT23 footprint compatibility with space-constrained industrial power stages.

Technical Context

This PNP transistor employs an advanced silicon process to achieve high breakdown voltage while maintaining low saturation voltage and usable h_FE (20–300) across operating current range. Its -7 V V_EBO and -7 V V_ECO define strict reverse-bias limits for emitter-base and emitter-collector junctions.

The device operates with linear derating from 1.25 W at 25 °C to zero at 150 °C junction temperature when mounted on 50 mm × 50 mm PCB with 2 oz copper. Turn-on/turn-off times (102 ns / 854 ns) reflect optimized charge storage for moderate-speed switching applications.

Key Specifications

Pinout & Package

SOT23-3 plastic surface-mount package with gull-wing leads; compact 2.67 mm × 1.20 mm footprint, 1.10 mm max height, and JEDEC-standard pin assignment.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTP25140BFHTA, ZXTP2012Z trades 40 V blocking headroom and 90 mV higher V_CE(sat) for lower unit cost, while MMDT3906 serves entirely different current/voltage classes and cannot replace it in power switching roles.

Availability

ZXTP25140BFHTA is available at Aetrix Electronics and suitable for DC-DC converters, industrial high-side load switches, and LED string drivers requiring stable component supply with consistent SOT23 packaging and traceable lot history.

Supply support for ZXTP25140BFHTA 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 acquired Zetex Semiconductors in 2008 and maintains its high-performance discrete portfolio with focus on power efficiency and reliability in industrial and automotive applications.

This device belongs to Zetex's medium-power PNP transistor product line, engineered specifically for high-voltage, high-current switching in compact surface-mount formats where thermal and space constraints preclude TO-220 or DPAK solutions.

FAQ

What is the maximum safe operating voltage for ZXTP25140BFHTA in a high-side switch configuration?

The absolute maximum collector-emitter voltage with base open (V_CEO) is -140 V, and forward blocking voltage (V_CEX) is -180 V under specified test conditions. For reliable high-side operation, design must maintain V_CE ≤ -126 V to provide 10% margin against V_CEO derating at elevated temperatures.

Can ZXTP25140BFHTA be driven directly from a 3.3 V microcontroller GPIO?

No-direct 3.3 V drive is insufficient because the base-emitter turn-on voltage is -800 to -900 mV, and -100 mA base current is required for full saturation at -1 A collector current. A level-shifting driver or external pull-up to ≥5 V with current-limiting resistor is necessary to ensure robust switching.

How does PCB layout affect the thermal performance of ZXTP25140BFHTA?

Thermal resistance varies significantly with copper area: R_JA is 171 °C/W on 15 mm × 15 mm board but improves to 100 °C/W on 50 mm × 50 mm with 2 oz copper. To sustain 1.25 W dissipation, minimum recommended copper pour is 25 mm² connected to pin 3 (collector) and pin 1 (emitter) with multiple vias to inner layers.

Is ZXTP25140BFHTA suitable for linear regulator pass transistor applications?

It can operate in linear mode but is optimized for switching-its f_T of 75 MHz and h_FE variation across current range make it less stable than purpose-built pass transistors. For linear regulators, verify thermal design at worst-case dropout and load, as power dissipation scales with (V_IN – V_OUT) × I_LOAD, not just I_C.