Diodes Incorporated ZDT6758TA

Overview

ZDT6758TA from Diodes Incorporated is a complementary medium-power bipolar transistor pair (NPN+PNP) in a single SM-8 (SOT-223-8) package, rated for 400 V V_CEO, 0.5 A continuous I_C, and 2.25 W dissipation per die. It serves as a high-voltage switching or linear amplification stage in offline power supplies, relay drivers, and industrial motor control interfaces where dual-polarity gain and breakdown robustness are required.

For engineers reviewing the ZDT6758TA datasheet, ZDT6758TA pinout, ZDT6758TA application, or ZDT6758TA equivalent, key selection criteria include verified 400 V breakdown symmetry, matched h_FE (50–40 across 1–200 mA), pulsed switching times (130/3300 ns NPN; 140/2000 ns PNP), thermal resistance (55.6 °C/W single-die), and SM-8 footprint compatibility with PCB copper area constraints.

Technical Context

The ZDT6758TA integrates electrically isolated NPN and PNP silicon planar transistors on one die substrate, sharing no internal connection-enabling independent biasing and true complementary operation. Each transistor supports 400 V blocking capability, 5 V V_EBO, and exhibits identical f_T = 50 MHz under ±20 mA/±20 V conditions.

Thermal derating is defined separately for single-die (18 mW/°C) and dual-die (22 mW/°C) operation, reflecting its dual-die thermal coupling behavior on a 2-inch² PCB copper pad. Switching performance is characterized under pulsed conditions (300 µs width, ≤2% duty cycle) to avoid self-heating artifacts.

Key Specifications

Pinout & Package

Package: SM-8 (8-lead SOT-223 variant), thermally enhanced with two isolated emitter pads and separate collector tabs per transistor. Mounting requires ≥2 inch² of 2-oz copper on PCB for rated power dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar complementary high-voltage transistor applications.

Compared with ZTX653/ZTX753 and BCX69/BCX70, the ZDT6758TA uniquely delivers integrated 400 V complementary operation in a single SM-8 package with coordinated thermal derating - critical for compact, high-reliability offline power and industrial actuation.

Availability

ZDT6758TA is available at Aetrix Electronics and suitable for AC-DC adapter primary switches, industrial relay drivers, linear regulator pass elements, and half-bridge gate driver stages requiring stable component supply and long-term manufacturability.

Supply support for ZDT6758TA 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 industrial and automotive markets.

The ZDT6758TA belongs to Diodes' high-voltage complementary transistor family, engineered specifically for space-constrained, high-breakdown industrial power interfaces where thermal coupling and layout symmetry improve system efficiency and EMI performance.

FAQ

What is the maximum safe operating voltage for ZDT6758TA in continuous DC applications?

The ZDT6758TA supports continuous DC operation up to ±400 V V_CEO and ±400 V V_CBO per transistor, provided ambient temperature remains ≤70°C and PCB copper area meets the 2-inch² requirement. Derating is mandatory above 25°C ambient - 18 mW/°C for single-die use, 22 mW/°C for dual-die simultaneous operation.

Can ZDT6758TA be used in linear amplifier configurations?

Yes - its h_FE stability (50 min @ 1 mA, 40 min @ 200 mA), low V_CE(sat), and matched NPN/PNP characteristics support Class-B and Class-AB linear amplifiers up to ~100 kHz. Thermal runaway risk is mitigated by the SM-8 package's low R_θJA (55.6 °C/W), but emitter degeneration resistors are recommended for bias stability.

Does ZDT6758TA require external base resistors for microcontroller GPIO drive?

Yes - direct GPIO connection risks excessive base current due to low V_BE(sat) (0.9 V) and typical h_FE of 50. For 3.3 V or 5 V logic driving 100 mA collector current, a 1 kΩ series resistor limits base current to ~2.4 mA (3.3 V) or ~4.1 mA (5 V), ensuring saturation while protecting the MCU output stage.

How does the SM-8 package differ from standard SOT-223 in thermal performance?

The SM-8 is an 8-lead variant of SOT-223 with doubled collector and emitter terminals per transistor - enabling separate high-current paths and improved thermal spreading. Its R_θJA is 55.6 °C/W (single die) versus ~125 °C/W for standard SOT-223, achieved via larger copper contact area and internal lead-frame design optimized for 2-inch² PCB mounting.