STMicroelectronics STD1802T4

Overview

STD1802T4 from STMicroelectronics is a low-voltage, fast-switching NPN power transistor in DPAK (TO-252) package, rated for 60 V V_CEO, 3 A I_C, and 15 W P_tot at T_c ≤ 25°C, with V_CE(sat) as low as 150 mV at I_C = 2 A / I_B = 100 mA, used in CCFL drivers and low-voltage switching regulators.

For engineers reviewing the STD1802T4 datasheet, STD1802T4 pinout, STD1802T4 application, or STD1802T4 equivalent, key selection criteria include saturation voltage at high current, DC current gain stability across operating range, thermal resistance (R_thj-case = 8.33 °C/W), and DPAK surface-mount compatibility for high-power density layouts.

Technical Context

This NPN planar transistor uses "Base Island" layout to achieve high h_FE (200–400 at I_C = 100 mA) while maintaining ultra-low V_CE(sat) (≤300 mV at I_C = 3 A). Its f_T of 150 MHz supports fast switching in resistive and inductive loads.

Designed for operation up to 150 °C junction temperature, it features low C_CBO (50 pF) and fast switching times: t_ON = 50 ns, t_s = 1.35 µs, t_f = 120 ns under standardized 1 A/30 V resistive load conditions.

Key Specifications

Pinout & Package

DPAK (TO-252) surface-mount package with exposed drain-connected tab (pin 3) for thermal and electrical connection; molded plastic body with gull-wing leads; JEDEC-compliant ECOPACK® lead-free finish.

Key Features

Applications

Availability

STD1802T4 is available at Aetrix Electronics and suitable for CCFL drivers, voltage regulators, relay drivers, and high-efficiency low-voltage switching applications requiring stable component supply and long-term manufacturability.

Supply support for STD1802T4 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, digital, and mixed-signal ICs, discrete devices, and MEMS sensors for industrial, automotive, and consumer markets.

The STD1802 belongs to ST's low-voltage power transistor family, engineered specifically for high-gain, low-saturation switching in space-constrained, thermally demanding applications such as display backlighting and point-of-load regulation.

FAQ

What is the maximum continuous collector current for STD1802T4 at 100°C case temperature?

At T_c = 100°C, the device's maximum continuous collector current is derated to approximately 1.8 A, based on the linear derating curve in Figure 2 of the datasheet (15 W → 0 W over 125°C range). This reflects thermal limitation-not electrical-so operation above this requires active cooling or reduced duty cycle.

Can STD1802T4 replace a MOSFET in a 5 V logic-level gate-driven circuit?

No-STD1802T4 is an NPN bipolar transistor requiring base current drive (≥100 mA for full saturation), unlike logic-level MOSFETs that accept voltage-controlled gate signals. It lacks gate threshold voltage or R_DS(on); substituting it demands redesign of drive circuitry and accounting for base power dissipation.

Is the DPAK tab electrically isolated from the collector?

No-the metal tab (pin 3) is internally connected to the collector terminal. This is confirmed by the internal schematic (Figure 1) and mechanical drawings showing tab continuity with collector leadframe. Thermal mounting must maintain electrical isolation if collector is not at system ground potential.

Does STD1802T4 meet automotive AEC-Q101 stress test requirements?

No-STD1802T4 is not qualified to AEC-Q101. The datasheet contains no automotive qualification statement, and its revision history and packaging documentation reference only industrial-grade ECOPACK® compliance. For automotive use, ST recommends AEC-Q101-qualified alternatives like the STL180N4LF5.