Diodes Incorporated FZT789ATA

Overview

FZT789ATA from Diodes Incorporated is a 25V PNP medium-power transistor in SOT223 package, rated for -3A continuous collector current, with V_CE(sat) < -250mV at -1A and R_CE(sat) = 93mΩ. It delivers high DC current gain (h_FE = 300–800 at -10mA) and supports fast switching (t_on = 35ns, t_off = 400ns), enabling use in power MOSFET/IGBT gate driving circuits.

For engineers reviewing the FZT789ATA datasheet, FZT789ATA pinout, FZT789ATA application, or FZT789ATA equivalent, key selection criteria include its AEC-Q101 qualification, low saturation resistance, thermal performance on 25mm×25mm 2oz copper, complementary pairing with FZT689B, and suitability for battery-powered fast-charge converters requiring stable high-current PNP switching.

Technical Context

This PNP bipolar junction transistor operates with a maximum V_CEO of -25V and V_CBO of -30V, supporting robust blocking in medium-voltage power control stages. Its f_T = 100MHz enables reliable operation in high-speed gate drive and pulse-width modulation applications up to several MHz.

The device exhibits specified h_FE down to -6A, ensuring predictable current amplification under peak load conditions. Thermal resistance R_θJA is 62.5°C/W when mounted on 25mm×25mm 2oz FR4, directly informing heatsinking requirements for sustained 2A–3A conduction.

Key Specifications

Pinout & Package

SOT223 package: surface-mount, 4-pin thermally enhanced plastic case with exposed collector tab (pin 3); molded "Green" compound, UL 94V-0 rated, 0.112g weight.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBT789A, FZT789ATA provides 2× continuous current, 40% lower conduction loss, and automotive qualification; versus FZT689B, it offers complementary polarity for bidirectional control but shares identical thermal and switching performance in matching layouts.

Availability

FZT789ATA is available at Aetrix Electronics and suitable for power MOSFET gate driving, battery-powered circuits, and fast charge converters requiring stable component supply, AEC-Q101 compliance, and consistent SOT223 thermal performance.

Supply support for FZT789ATA 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 components for automotive, industrial, and consumer markets.

The FZT789ATA belongs to Diodes' high-performance bipolar transistor product line, engineered for demanding power switching applications where low saturation voltage, fast switching, and AEC-Q101 reliability are essential.

FAQ

What is the maximum allowable junction temperature for FZT789ATA?

The FZT789ATA has an operating junction temperature range of -55°C to +150°C. Its absolute maximum T_J is +150°C; sustained operation above this threshold risks permanent degradation. Derating curves in the datasheet specify that power dissipation must be reduced linearly beyond +25°C ambient when mounted on 25mm×25mm 2oz copper.

Is FZT789ATA pin-compatible with other SOT223 PNP transistors?

FZT789ATA uses standard SOT223 pinout (E-B-C-C), matching industry convention. However, electrical parameters-including V_CEO, h_FE, and R_CE(sat)-differ significantly across manufacturers. Direct substitution requires verification of gain linearity, saturation voltage at target I_C, and thermal resistance under identical PCB layout conditions.

Does FZT789ATA require a base resistor in gate-driving applications?

Yes. To achieve full saturation at -1A collector current, the datasheet specifies -10mA base drive. A series base resistor (e.g., 1kΩ with -10V drive) is required to limit base current and prevent damage. Omission risks excessive base-emitter dissipation and gain compression due to thermal runaway.

How does the dual-collector pin (pins 3 and 4) improve thermal performance?

Pins 3 and 4 are internally shorted to the same collector node and externally connected to a shared copper pour. This doubles the solder joint area and thermal conduction path from die to PCB, reducing R_θJA by ~20% compared to single-collector SOT223 variants and enabling 20–30% higher continuous current in identical layouts.