Diodes Incorporated FMMTL718TA

Overview

FMMTL718TA from Diodes Incorporated is a 20V PNP silicon low-saturation transistor in SOT-23 package, designed for high-current switching with V_CE(sat) < −320 mV at −1 A, h_FE ≥ 200 up to −1.5 A, and 500 mW power dissipation. It serves as a robust power switch in DC-DC converters, MOSFET gate drivers, and battery charging circuits.

For engineers reviewing the FMMTL718TA datasheet, FMMTL718TA pinout, FMMTL718TA application, or FMMTL718TA equivalent, key selection criteria include guaranteed −20 V V_CEO, pulsed I_CM = −2 A, thermal resistance R_θJA = 250 °C/W on FR4, AEC-Q101 qualification, and complementary pairing with FMMTL618.

Technical Context

This PNP bipolar junction transistor operates in linear and saturated switching modes, with breakdown ratings of −20 V (V_CEO, V_CBO) and −5 V (V_EBO). Its h_FE is characterized across five current levels (−10 mA to −1.5 A), ensuring predictable gain hold-up under heavy load conditions.

V_CE(sat) is specified down to −315 mV at −1 A / −50 mA base drive, enabling efficient low-loss switching. Transition frequency f_T = 265 MHz and output capacitance C_obo = 9–12 pF support fast turn-on (t_on = 108 ns) and turn-off (t_off = 121 ns) in high-frequency power control applications.

Key Specifications

Pinout & Package

Package: SOT-23 - surface-mount plastic case, UL 94V-0 rated, 0.008 g weight, matte tin-plated Alloy 42 leadframe, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP low-saturation transistor applications.

Compared with DMT3005LKQ and FMMT718, FMMTL718TA uniquely balances AEC-Q101 compliance, −320 mV saturation voltage at −1 A, and −20 V rating-making it optimal for space-constrained automotive DC-DC and gate drive stages where thermal and reliability margins are critical.

Availability

FMMTL718TA is available at Aetrix Electronics and suitable for DC-DC converters, MOSFET gate drivers, and battery charging circuits requiring stable component supply, automotive-grade reliability, and consistent SOT-23 packaging.

Supply support for FMMTL718TA 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, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

FMMTL718TA belongs to Diodes' FMMT/FMMTL series of high-reliability bipolar transistors engineered specifically for automotive power switching, gate driving, and precision current regulation in harsh environments.

FAQ

What is the maximum allowable base current for continuous operation?

The absolute maximum continuous base current is −200 mA per the datasheet's "Maximum Ratings" table. However, for reliable long-term operation at −1 A collector current, the recommended base drive is −50 mA to ensure deep saturation without excessive base power dissipation or thermal stress on the bond wires.

Is FMMTL718TA suitable for linear regulator applications?

Yes-it supports linear operation with guaranteed h_FE down to −1.5 A and V_CE(sat) as low as −315 mV. Its R_θJA = 250 °C/W requires careful thermal design: at 500 mW dissipation, junction temperature rises ~125 °C above ambient, limiting usable dropout voltage and load current in unheatsinked configurations.

How does the "L" suffix in FMMTL718TA differ from FMMT718?

The "L" denotes AEC-Q101 qualification-verified performance across −55 °C to +150 °C, including temperature cycling, mechanical shock, and humidity testing. Electrically identical to FMMT718, the "L" version adds automotive-grade traceability, lot-level reliability data, and extended test coverage per JESD47 standards.

Can FMMTL718TA replace a small-signal PNP like BC807 in gate drive circuits?

Only if the BC807's −500 mA I_C rating is insufficient. FMMTL718TA delivers −1 A continuous current and −2 A pulse capability with significantly lower V_CE(sat), but its higher base drive requirement (−50 mA vs. −5 mA) demands stronger driver circuitry. It is not a drop-in replacement without revising base resistor values and verifying driver strength.