Diodes Incorporated FZT853TA

Overview

FZT853TA from Diodes Incorporated is a 100V NPN medium-power transistor in SOT223 package, designed for high-current switching and linear regulation. It delivers 6A continuous collector current, 10A peak pulse current, and low saturation voltage (14–150mV @ 100mA–2A), with guaranteed hFE ≥50 at 4A and ≥20 at 10A. It is AEC-Q101 qualified and used in automotive power supplies and industrial DC-DC converters.

For engineers reviewing the FZT853TA datasheet, FZT853TA pinout, FZT853TA application, or FZT853TA equivalent, key selection criteria include V_CEO = 100V, R_CE(SAT) = 50 mΩ, thermal resistance R_θJA = 42 °C/W (on 52 mm × 52 mm 2 oz Cu), ESD HBM rating of 8 kV, and complementary PNP pairing with FZT953TA.

Technical Context

This NPN bipolar junction transistor operates in both linear and saturated switching modes, with BV_CEO = 100 V and BV_CBO = 200 V enabling use in 48V–72V bus systems. Its hFE remains ≥20 up to I_C = 10 A, supporting high-gain hold-up under heavy load transients.

The device features low V_CE(SAT) (14 mV typ. @ 100 mA) and R_CE(SAT) = 50 mΩ, minimizing conduction loss in high-efficiency power stages. Thermal performance is defined for two PCB mounting conditions: R_θJA = 42 °C/W (52 mm × 52 mm 2 oz Cu) and 78 °C/W (25 mm × 25 mm 1 oz Cu).

Key Specifications

Pinout & Package

Package: SOT223 - surface-mount, 4-pin (3 active + tab), thermally enhanced plastic case with exposed collector lead (pin 3) acting as heatsink interface. Weight: 0.112 g. Moisture sensitivity level: MSL 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTN25050DFH and MJD127G, FZT853TA uniquely balances 6 A current, 100 V rating, AEC-Q101 compliance, and SOT223 thermal performance-making it optimal for space-limited automotive and industrial switching where reliability and surface-mount compatibility are mandatory.

Availability

FZT853TA is available at Aetrix Electronics and suitable for automotive LED drivers, 48V DC-DC converters, telecom power shelf redundancy, and EV precharge circuits requiring stable component supply and long-term lifecycle assurance.

Supply support for FZT853TA 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 power management, signal integrity, and protection solutions for automotive, industrial, and computing markets.

FZT853TA belongs to Diodes' AEC-Q101-qualified medium-power transistor family, engineered for robust high-current switching in harsh-environment applications where thermal stability, voltage margin, and process consistency are critical.

FAQ

What is the maximum allowable junction temperature for FZT853TA?

The absolute maximum junction temperature is +150°C, and the device is rated for continuous operation across -55°C to +150°C ambient. Derating begins above +25°C ambient per the published R_θJA curves-e.g., at +85°C ambient, max continuous power drops to ~1.8 W on 52 mm × 52 mm 2 oz Cu PCB.

Can FZT853TA replace a MOSFET in high-frequency switching applications?

No-it is a bipolar transistor with inherent minority-carrier storage delay; t_OFF = 1650 ns limits practical use to ≤200 kHz switching. For >500 kHz, a logic-level MOSFET with low Q_g and R_DS(on) is preferred. FZT853TA excels in lower-frequency, high-current linear or saturated switching where gain and ruggedness matter more than speed.

Is the exposed tab electrically isolated from other pins?

No-the SOT223 tab is internally connected to the collector (Pin 3). Pin 4 is a second collector lead. Both must be tied to the same collector potential. The tab must be soldered to a dedicated collector net and thermal pad; isolation from ground or emitter is mandatory to prevent short circuits.

Does FZT853TA require a base resistor in all applications?

Yes-base current must be actively limited to avoid damage. With hFE ≈ 25 at 5 A, ~200 mA base drive is needed; using a 5 Ω resistor with 1.2 V V_BE(SAT) yields ~240 mA, ensuring saturation. Undriven or open-base operation risks thermal runaway due to secondary breakdown susceptibility at high V_CE.