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FZT605TA

DIOFZT605TA

Diodes Incorporated
Bipolar (BJT) Transistor NPN - Darlington 120 V 1.5 A 150MHz 2 W Surface Mount SOT-223-3
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Overview

The FZT605TA is a high-performance NPN Darlington transistor designed for applications requiring high current gain and high voltage handling. It features a collector-emitter voltage of 120 V and a continuous collector current rating of 1.5 A, packaged in a surface-mount SOT-223 for efficient thermal dissipation. This device is particularly effective for interfacing low-power logic circuits with high-power loads.

Why Choose This Part

The Darlington configuration provides extremely high current gain, allowing for minimal base drive current. With a 120 V rating and 2 W power dissipation capability in a compact SOT-223 package, it offers a robust solution for medium-power switching without the footprint of a TO-220 device.

Applications

Solenoid and Relay Driving
Utilizes high current gain to switch inductive loads directly from low-current microcontroller outputs.
Lamp and LED Driving
Manages high-voltage lighting strings and high-current indicators up to 1.5 A.
Power Linear Regulators
Acts as a pass element in linear power supplies where high input-to-output voltage differentials are present.
Actuator Control
Provides the necessary current amplification for driving small DC motors or thermal actuators in industrial environments.

Key Specifications

Power - Max 2 W
Mounting Type Surface Mount
Package / Case TO-261-4, TO-261AA
Transistor Type NPN - Darlington
Operating Temperature -55degC ~ 150degC (TJ)
Frequency - Transition 150MHz
Supplier Device Package SOT-223-3
Vce Saturation (Max) @ Ib, Ic 1.5V @ 1mA, 1A
Current - Collector (Ic) (Max) 1.5 A
Current - Collector Cutoff (Max) 10uA
DC Current Gain (hFE) (Min) @ Ic, Vce 2000 @ 1A, 5V
Voltage - Collector Emitter Breakdown (Max) 120 V

Getting Started

When designing with the FZT605TA, ensure adequate PCB copper area is connected to the collector tab to manage the 2 W power dissipation rating. Account for the higher Vce(sat) characteristic of Darlington pairs, which reaches 1.5 V at 1 A, to calculate thermal losses accurately. For switching inductive loads like relays, always include a freewheeling diode across the load to protect the transistor from back-EMF spikes.

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