Diodes Incorporated ZX5T869GTA

Overview

ZX5T869GTA from Zetex (now Diodes Incorporated) is a 25V NPN low-saturation transistor in SOT223 package, designed as a high-current switching element with V_CE(SAT) = 40 mV at I_C = 6.5A, R_SAT = 27 mΩ, and continuous I_C = 7 A. It serves as a power switch or MOSFET gate driver in DC-DC converters and motor control circuits.

For engineers reviewing the ZX5T869GTA datasheet, ZX5T869GTA pinout, ZX5T869GTA application, or ZX5T869GTA equivalent, key selection criteria include verified V_CE(SAT) at 6.5A, h_FE ≥ 300 at 1A, thermal resistance R_JA = 42°C/W on 52mm × 52mm 2oz copper, and SOT223 pin-compatible layout for board-level replacement.

Technical Context

This device uses a 5th-generation epitaxial planar NPN structure optimized for low saturation voltage and high current gain across wide operating ranges. Its BVCER = 60 V (with R_B = 1 kΩ) and BV_CEO = 25 V support robust switching in regulated power rails up to 24 V.

It delivers h_FE = 400 at I_C = 10 mA and maintains h_FE = 90 at I_C = 20 A, enabling stable current amplification in both linear and saturated switching modes. Switching times are t_ON = 33 ns and t_OFF = 464 ns under defined 1A/100mA drive conditions.

Key Specifications

Pinout & Package

Package: SOT223 - surface-mount, 4-pin outline with exposed collector tab (pin 3) for thermal enhancement and electrical connection. Standard JEDEC MO-178 variant with 3.3–3.7 mm E1 width and 6.3–6.7 mm D length.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTN25050DFH, ZX5T869GTA delivers 64% lower V_CE(SAT) at rated current and superior thermal performance; versus DMT3020LPSQ, it avoids gate-drive complexity but trades off slightly higher conduction loss than MOSFET's R_DS(on).

Availability

ZX5T869GTA is available at Aetrix Electronics and suitable for DC-DC converters, motor control systems, and battery charging circuits requiring stable component supply, long-term manufacturability, and consistent parametric performance across production lots.

Supply support for ZX5T869GTA 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

Zetex Semiconductors (acquired by Diodes Incorporated in 2008) specialized in high-performance discrete transistors and analog ICs, with engineering centers in UK, Germany, and US.

This part belongs to Zetex's "ZXT" low-saturation bipolar transistor family, developed specifically for high-efficiency power conversion and gate driving where MOSFET gate charge and drive complexity are limiting factors.

FAQ

What is the maximum safe operating current for ZX5T869GTA in continuous DC mode?

The absolute maximum continuous collector current is 7 A at T_A = 25°C with proper PCB copper area. Derating applies per the 24 W power limit and 24 mW/°C linear slope - at 70°C ambient, max I_C drops to ~5.2 A assuming R_JA = 42°C/W. Exceeding this risks thermal runaway due to positive temperature coefficient of V_CE(SAT).

Can ZX5T869GTA replace a MOSFET in a synchronous buck converter?

Yes - as a low-side synchronous rectifier, provided gate drive is replaced with appropriate base current limiting (e.g., 150 mA via 10 Ω resistor from 1.8V logic). Its 40 mV V_CE(SAT) at 6.5A yields lower conduction loss than many 30V MOSFETs with R_DS(on) > 6 mΩ, though switching loss may be higher above 500 kHz due to minority-carrier storage.

Is the exposed tab electrically isolated from other pins?

No - the metal tab is internally connected to pin 3 (collector) and pin 4 (collector), forming a single low-impedance collector node. It must be soldered to a PCB copper pour tied to the collector net. Insulating the tab creates thermal bottleneck and violates JEDEC SOT223 mechanical specification.

Does ZX5T869GTA support parallel operation for higher current?

Not recommended without external emitter ballasting resistors. h_FE variation (±20%) and positive V_CE(SAT) temperature coefficient cause current imbalance - one device may carry >60% of total load at elevated temperature. For >7 A, use a single higher-rated device or implement active current sharing.