FMMTA42TA – ZETEX

Overview

The Diodes Incorporated FMMTA42TA is a high-voltage NPN bipolar junction transistor (BJT) designed for general-purpose amplification and switching applications where significant voltage standoff is paramount. Its key operational characteristic is the impressive 300V collector-emitter breakdown voltage, enabling its use in circuits that must withstand substantial transient overvoltages. A critical design consideration, however, is the relatively low maximum collector current of 200mA, which necessitates careful thermal management and current limiting to prevent premature device failure, especially when operating near its power dissipation limit of 330mW.

Key Features

• Collector-Emitter Breakdown Voltage (Vceo): 300V
• Continuous Collector Current (Ic): 200mA
• Maximum Power Dissipation: 330mW
• Transition Frequency (fT): 50MHz
• DC Current Gain (hFE) Min @ Ic, Vce: 40 @ 30mA, 10V
• Package: SOT-23-3 (TO-236-3, SC-59)

Applications

The component is engineered for deployment in systems requiring high reliability and performance under specific operating conditions. It provides functional stability across the stated design envelope.

• High-voltage switching in power supply pre-regulators
• Series pass transistor in low-current, high-voltage linear regulators
• Driving high-impedance loads in signal conditioning circuits
• Protection circuitry for sensitive downstream components from voltage spikes