Diodes Incorporated FZT591TC

Overview

FZT591TC from Diodes Incorporated is a 60V PNP medium-power bipolar junction transistor in SOT223 package, rated for -1A continuous collector current, with V_CE(sat) < -600 mV at -1A/-100 mA drive, and BV_CEO = -60 V. It serves as a high-current switching element in gate-drive and power-conversion stages of industrial motor controllers and DC-DC converters.

For engineers reviewing the FZT591TC datasheet, FZT591TC pinout, FZT591TC application, or FZT591TC equivalent, key selection criteria include verified PNP saturation voltage under 1A load, thermal resistance to ambient (41.7°C/W on 50mm×50mm 2oz Cu), complementary pairing with FZT491, and AEC-Q101 readiness via Q-suffix variants.

Technical Context

This PNP transistor operates in linear or saturated switching mode with guaranteed h_FE ≥ 100 at IC = -1 mA and ≥ 80 at IC = -500 mA, supporting stable current gain across bias conditions. Its f_T = 150 MHz enables use in moderate-speed switching applications up to several hundred kHz.

Thermal design is constrained by R_θJA values ranging from 41.7°C/W (optimal layout) to 104°C/W (minimum pad), requiring explicit PCB copper planning. ESD robustness is confirmed at 8 kV HBM (JEDEC Class 3B), suitable for assembly environments without ultra-stringent handling controls.

Key Specifications

Pinout & Package

Package: SOT223 (Type DN), surface-mount, 4-terminal configuration with collector tab electrically connected to lead 1 (collector) and thermally enhanced via exposed copper pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTN25050DFH and MJD44H11T4G, FZT591TC uniquely balances 1A current capability, low 600 mV saturation, SOT223 thermal performance, and complementary pairing-making it optimal for compact, thermally managed gate-drive circuits where both current and voltage ratings must be simultaneously met.

Availability

FZT591TC is available at Aetrix Electronics and suitable for motor drive gate control, industrial DC-DC converter design, and automotive HVAC blower control requiring stable component supply and consistent parametric performance across production lots.

Supply support for FZT591TC 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 distribution operations across Asia, Europe, and the Americas.

FZT591TC belongs to Diodes' medium-power bipolar transistor product line, engineered specifically for high-reliability industrial and automotive gate-driving and power-switching applications demanding robust voltage rating and thermal efficiency.

FAQ

What is the maximum safe operating temperature for FZT591TC?

The FZT591TC has an operating junction temperature range of -55°C to +150°C. With R_θJA = 41.7°C/W on optimized PCB layout, sustained 1A operation at 25°C ambient yields ~105°C junction temperature-within safe limits. Derating is required above 100°C ambient per the datasheet's thermal curves.

Is FZT591TC pin-compatible with FZT491?

No-FZT591TC (PNP) and FZT491 (NPN) share identical SOT223 package and pinout (Emitter-Base-Collector-Collector), but opposite polarity. Their complementary pairing enables matched push-pull designs, not drop-in substitution. Both use Pin 1 as collector tab and Pin 3 as emitter/base respectively.

Does FZT591TC require a heatsink in standard applications?

A dedicated heatsink is not required if mounted on ≥25 mm × 25 mm 2 oz copper per the datasheet's thermal notes. On minimum pad layout (R_θJA = 104°C/W), 1A operation exceeds 150°C junction at 25°C ambient-so adequate PCB copper area serves as the primary thermal solution instead of external heatsinks.

Can FZT591TC be used in linear amplifier configurations?

Yes-its h_FE stability (100–300) and f_T = 150 MHz support low-distortion linear operation up to ~100 kHz. However, power dissipation must remain below 1.2–3.0 W depending on layout, and V_CE should stay within -5 V to -30 V to avoid second breakdown, per the Safe Operating Area curves in DS33142.