Diodes Incorporated ZXTN25020BFHTA

Overview

ZXTN25020BFHTA from Diodes Incorporated (formerly Zetex Semiconductors) is an NPN medium-power bipolar junction transistor in SOT23 package, rated for 20V V_CEO, 4.5A continuous collector current, and 1.25W power dissipation on a 50mm×50mm PCB. It delivers V_CE(sat) ≤ 45 mV at I_C = 1A / I_B = 100mA and supports MOSFET gate driving, DC-DC converter switching, and motor control stages.

For engineers reviewing the ZXTN25020BFHTA datasheet, ZXTN25020BFHTA pinout, ZXTN25020BFHTA application, or ZXTN25020BFHTA equivalent, key selection criteria include its low saturation voltage, 50V forward blocking capability, thermal performance on standard FR4 layouts, and compatibility with high-current pulse drive requirements in compact power stages.

Technical Context

This NPN BJT uses an advanced epitaxial process to achieve high current gain (h_FE = 75–160 at I_C = 4.5A) and fast switching (t_d = 87 ns, t_f = 61 ns) under hard-saturation conditions. Its 50V V_CEX rating enables use in circuits with transient overvoltage margins beyond nominal 20V rail operation.

The device exhibits low R_CE(sat) of 27 mΩ at I_C = 1A and maintains stable f_T = 185 MHz at I_C = 50mA/V_CE = 10V, supporting high-frequency switching while retaining robust DC conduction capability.

Key Specifications

Pinout & Package

SOT23-3 package: compact surface-mount outline with gull-wing leads, 1.2–1.4 mm body width, 2.67–3.05 mm length, and 1.9 mm height. Designed for automated placement and reflow soldering on standard PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN medium-power switching applications.

Compared with ZXTN25020BFHTA, ZXTN2010ZTA trades lower conduction loss for higher voltage resilience, while MMBT4401LT1G lacks both current and saturation performance - making ZXTN25020BFHTA uniquely balanced for 1–4.5A, 20V-class power switching where efficiency and board space are constrained.

Availability

ZXTN25020BFHTA is available at Aetrix Electronics and suitable for MOSFET gate drivers, brushed DC motor control, and DC-DC converter power stages requiring stable component supply across production volumes.

Supply support for ZXTN25020BFHTA 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 integrates its high-performance analog and discrete portfolio into broad power management and signal solutions.

ZXTN25020BFHTA belongs to Zetex's medium-power BJT family, engineered specifically for space-constrained, high-current switching in power conversion and motor drive applications.

FAQ

What is the maximum allowable continuous collector current for ZXTN25020BFHTA?

The maximum continuous collector current is 4.5 A when mounted on a 50 mm × 50 mm × 1.6 mm FR4 PCB with high-coverage 2 oz copper. This rating assumes still-air conditions and drops linearly by 9.6 mW/°C above 25°C ambient temperature. Derating must be applied for smaller PCBs or higher ambient temperatures per the datasheet's R_JA values.

Can ZXTN25020BFHTA replace a MOSFET in low-side switching applications?

ZXTN25020BFHTA functions as a saturated BJT switch-not a voltage-controlled MOSFET-and requires sufficient base current (e.g., 100 mA for 1A collector load) to maintain low V_CE(sat). It is appropriate where drive capability and PCB area outweigh gate charge and R_DS(on) advantages; however, it cannot match MOSFET efficiency at high frequencies or low voltages due to inherent V_CE(sat) and base drive losses.

What is the recommended base resistor value for driving ZXTN25020BFHTA from a 3.3V microcontroller GPIO?

For reliable saturation at I_C = 1A, a base current of ≥100 mA is required. With a 3.3V GPIO and typical V_BE(sat) ≈ 0.95 V, the base resistor should be ≤ (3.3 V − 0.95 V) / 0.1 A = 23.5 Ω. A standard 22 Ω, 0.25W resistor is appropriate, but ensure the MCU pin can source 100 mA continuously or use a buffer stage for sustained operation.

Does ZXTN25020BFHTA have built-in ESD protection?

No, ZXTN25020BFHTA does not incorporate on-chip ESD protection diodes. The absolute maximum rating for V_EBO is 7 V, and exposure to electrostatic discharge exceeding this-especially at the base terminal-can cause permanent damage. External series resistors and/or TVS diodes are recommended in handling and circuit design to protect the base-emitter junction during assembly and operation.