Diodes Incorporated FZT951TC

Overview

FZT951TC from Diodes Incorporated is a PNP silicon planar high-current bipolar junction transistor in SOT-223 package, rated for −5 A continuous collector current, −60 V V_CEO, and 3 W power dissipation at T_amb = 25°C; it delivers V_CE(sat) = −155 mV at −2 A / −200 mA drive and h_FE ≥ 75 up to −5 A, enabling robust switching in DC-DC converter output stages and industrial motor control H-bridge legs.

For engineers reviewing the FZT951TC datasheet, FZT951TC pinout, FZT951TC application, or FZT951TC equivalent, key selection criteria include verified PNP polarity, SOT-223 thermal performance with ≥4 in² copper, low R_CE(sat) (55 mΩ at −4 A), gain stability across −10 mA to −10 A, and complementary pairing with FZT851 for push-pull topologies.

Technical Context

This device operates as a medium-power PNP switch with fully specified gain (h_FE = 75–300) and saturation voltage (V_CE(sat) ≤ −210 mV at −5 A) across −55°C to +150°C junction temperature. Its f_T = 120 MHz and C_obo = 74 pF support fast switching in PWM-driven loads up to 100 kHz.

The SOT-223 package provides enhanced thermal resistance (R_θJA ≈ 42°C/W on 4 in² copper) versus standard SOT-23, enabling sustained −5 A conduction without forced air; safe operating area (SOA) curves confirm single-pulse capability to −15 A with 0.1 ms pulse width.

Key Specifications

Pinout & Package

SOT-223 package with exposed collector tab (pin 3) for thermal and electrical connection; molded plastic body with gull-wing leads; JEDEC TO-261AA outline; footprint compatible with automated reflow soldering.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP high-current switching applications.

Compared with ZXT951MATA and MJD2955T4G, FZT951TC uniquely balances −5 A current, −60 V rating, SOT-223 mountability, and sub-200 mV saturation in a single package-making it optimal for thermally dense, medium-voltage industrial SMPS where both efficiency and size matter.

Availability

FZT951TC is available at Aetrix Electronics and suitable for industrial DC-DC converters, motor control H-bridges, and LED constant-current drivers requiring stable component supply and long-term production continuity.

Supply support for FZT951TC 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 centers across Asia and manufacturing in China, Taiwan, and the U.S.

FZT951TC belongs to Diodes' high-performance bipolar transistor product line, engineered specifically for high-current, high-reliability industrial power switching where thermal efficiency and SOA robustness are critical.

FAQ

What is the maximum allowable junction temperature for FZT951TC?

The absolute maximum junction temperature is +150°C, and the storage temperature range is identical. Operation at this limit requires strict adherence to the SOA curves and thermal design guidelines-specifically, ≥4 in² of 2-oz copper on the collector pad and no ambient temperature exceeding +70°C for continuous −5 A operation.

Is FZT951TC pin-compatible with FZT953TC?

No-FZT951TC and FZT953TC share the same SOT-223 package and pinout (E-B-C-Tab), but they differ electrically: FZT953TC has −100 V V_CEO and −10 A I_CM, while FZT951TC is rated −60 V / −15 A. Substitution requires verification of voltage headroom and SOA compliance in the target circuit.

Does FZT951TC require a base resistor when driven by a microcontroller GPIO?

Yes-driving directly from a 3.3 V or 5 V GPIO requires a series base resistor to limit IB to ≤ −500 mA. For −5 A collector current, minimum h_FE = 75 implies ≥ −67 mA base current; typical design uses 100 Ω (for ~−45 mA at 5 V) with additional margin for temperature drift and gain variation.

Can FZT951TC be used in linear regulator applications?

Yes-its 3 W P_tot rating, SOA validation down to DC, and stable h_FE across current support linear pass-element use. However, thermal design must account for worst-case power dissipation: at −3 A and 5 V dropout, P_D = 15 W exceeds rating, so operation is limited to ≤1 A at 3 V dropout or active heatsinking.