STMicroelectronics 2STN2340

Overview

2STN2340 from STMicroelectronics is a PNP bipolar power transistor in SOT-223 package, designed for low-voltage fast-switching applications. It delivers V_CE(sat) = −250 mV at I_C = −2 A / I_B = −100 mA, h_FE = 100–450 (I_C = −0.1 to −3 A), and f_t = 100 MHz, enabling efficient DC-DC conversion and LED drive in space-constrained mobile equipment.

For engineers reviewing the 2STN2340 datasheet, 2STN2340 pinout, 2STN2340 application, or 2STN2340 equivalent, key selection criteria include its low saturation voltage, high current gain linearity across load range, thermal resistance of 78 °C/W (R_thJA), fast switching (t_on = 80 ns, t_off = 450 ns), and SOT-223 mechanical compatibility with PCB thermal pads.

Technical Context

This PNP transistor uses ST's PB-HDC (Power Bipolar High-Density Current) process to achieve simultaneous low V_CE(sat) and high h_FE, critical for minimizing conduction loss while maintaining drive efficiency in low-side switching configurations. Its −40 V V_CEO rating and −6 A I_CM peak current support robust operation in 12 V and 5 V rail systems.

The device operates with a maximum junction temperature of 150 °C and exhibits stable DC gain from I_C = −0.1 A to −3 A at V_CE = −2 V, confirming suitability for linear and saturated-mode control in motherboard VRMs and HDD actuator drivers.

Key Specifications

Pinout & Package

SOT-223 package with exposed collector tab (pin 3) for enhanced thermal conduction; molded plastic body compliant with ECOPACK® environmental specifications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP power switching applications.

Compared with 2STF2340, the 2STN2340 offers superior thermal performance in SOT-223, enabling higher continuous current in compact layouts; versus MJD2955T4G, it trades package robustness for speed and efficiency-critical in modern mobile and DC-DC applications.

Availability

2STN2340 is available at Aetrix Electronics and suitable for LED driver modules, hard disk drive actuator circuits, and mobile power management systems requiring stable component supply with consistent parametric performance across production lots.

Supply support for 2STN2340 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, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.

The 2STN2340 belongs to ST's PB-HDC bipolar power transistor family, engineered specifically for high-efficiency, low-voltage switching in space-sensitive portable and computing power systems.

FAQ

What is the maximum continuous collector current for 2STN2340 at 70 °C ambient?

At T_amb = 70 °C, derating begins at 150 °C junction limit. With R_thJA = 78 °C/W, allowable power dissipation drops to 1.03 W. Using V_CE(sat) = −350 mV at I_C = −3 A, max continuous I_C is approximately −2.9 A - verified via Figure 3 derating curve in Doc ID 14222 Rev 2, page 3.

Can 2STN2340 replace 2STF2340 in existing SOT-89 footprints?

No - 2STN2340 uses SOT-223 (6.5 × 3.5 mm, 4-pin) while 2STF2340 uses SOT-89 (4.6 × 2.6 mm, 3-pin). Pin count, pitch, and thermal pad layout differ. Mechanical redesign is required; however, electrical behavior is identical per Table 4, enabling functional validation after layout update.

Is 2STN2340 qualified for automotive applications?

No - the datasheet does not specify AEC-Q101 qualification, automotive temperature grade (−40 to 125 °C), or automotive-specific reliability testing. It is rated for industrial use (−65 to 150 °C T_J) but lacks automotive documentation; ST recommends using their Automotive-grade PNP transistors (e.g., BST50) for vehicle systems.

What base resistor value ensures full saturation at I_C = −3 A?

Per Table 4, V_CE(sat) = −350 mV is specified at I_C = −3 A / I_B = −150 mA. Assuming V_BB = −5 V and V_BE(sat) = −1.2 V, R_B = (−5 V + 1.2 V) / 0.15 A = 25.3 Ω. A standard 24 Ω ±5% resistor delivers 158 mA, ensuring robust saturation margin.