onsemi BD37916STU

Overview

BD37916STU from Fairchild Semiconductor is an NPN epitaxial silicon transistor designed for medium-power linear and switching applications, with V_CEO = 80 V, I_C = 2 A (DC), P_C = 25 W at T_C = 25°C, h_FE = 100–250 at I_C = 0.15 A, and V_CE(sat) = 1 V at I_C = 1 A / I_B = 0.1 A - used in audio output stages and relay drivers.

For engineers reviewing the BD37916STU datasheet, pinout, applications, or equivalent options, key selection factors include its TO-126 package, 80 V V_CEO, 2 A continuous collector current, safe operating area (SOA) compliance, and h_FE classification band "16" (100–250).

Technical Context

This NPN bipolar junction transistor operates in active, saturation, and cutoff regions with defined DC gain linearity across I_C = 0.15 A to 1 A. Its V_CEO(sus) = 80 V and BVCBO = 100 V support robust voltage blocking in inductive load switching.

The device features low V_CE(sat) = 1 V and V_BE(on) = 1.5 V at rated current, enabling efficient power stage operation. Thermal derating begins at T_C > 25°C, with T_J(max) = 150°C and T_STG = –55 to 150°C.

Key Specifications

Pinout & Package

BD37916STU is housed in a TO-126 plastic package with integral metal tab for heatsinking. Pin 1 = Emitter, Pin 2 = Collector (tab-connected), Pin 3 = Base - leads are straight-lead, through-hole mountable.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN medium-power switching and linear applications.

Compared with MJD31C and BD379G, BD37916STU offers tighter h_FE control (100–250) and legacy compatibility in TO-126 footprint, making it optimal for cost-sensitive, volume-manufactured audio and relay driver designs requiring predictable gain and proven reliability.

Availability

BD37916STU is available at Aetrix Electronics and suitable for audio power amplifiers, industrial relay drivers, DC motor controllers, and linear regulator pass applications requiring stable component supply and long-lifecycle support.

Supply support for BD37916STU 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

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete devices before its acquisition by ON Semiconductor in 2016.

BD37916STU belongs to the BD375/377/379 family of medium-power NPN transistors engineered for reliable linear amplification and robust switching in industrial, audio, and control systems.

FAQ

What is the hFE classification of BD37916STU and how does it affect circuit design?

The BD37916STU is classified as h_FE "16", meaning its DC current gain ranges from 100 to 250 when measured at V_CE = 2 V and I_C = 0.15 A. This tight binning allows designers to size base resistors with confidence, reducing gain-related variability in amplifier bias points and switch saturation margins. The BD37916STU's predictable h_FE simplifies production calibration and improves batch-to-batch consistency in audio and relay driver circuits.

Is BD37916STU pin-compatible with other devices in the BD375/377/379 series?

Yes, BD37916STU shares the same TO-126 package and identical pinout (Emitter–Collector–Base) with BD375 and BD377. However, absolute maximum ratings differ: BD37916STU has V_CEO = 80 V and V_CBO = 100 V, versus 45 V / 50 V for BD375. Direct substitution is only safe if the circuit operates within BD37916STU's higher voltage limits - never assume backward compatibility without verifying stress margins.

What thermal derating applies to BD37916STU above 25°C case temperature?

BD37916STU's collector dissipation decreases linearly above T_C = 25°C, with a thermal resistance of approximately 1.0°C/W (junction-to-case). At T_C = 75°C, its usable P_C drops to ~12.5 W. Derating follows the curve in Figure 5 of the datasheet, and operation beyond the Safe Operating Area (SOA) boundary - especially at high V_CE and I_C - risks secondary breakdown. Always verify thermal design using BD37916STU's published SOA graph.

Can BD37916STU be used in PWM motor control applications?

Yes, BD37916STU supports PWM motor control with t_ON = 50 ns and t_OFF = 500 ns under standard test conditions (V_CC = 30 V, R_L = 60 Ω). It is suitable for PWM frequencies up to ~200 kHz in low-duty-cycle, low-inductance loads. For 20 kHz+ operation with 1 A average current, ensure gate/base drive provides ≥0.1 A peak current to achieve full saturation, and verify SOA compliance during turn-on/turn-off transitions using BD37916STU's published SOA plot.

Does BD37916STU have built-in protection features such as thermal shutdown or overcurrent limiting?

No, BD37916STU is a discrete NPN bipolar transistor without integrated protection circuitry. It relies entirely on external design safeguards - including base current limiting, heatsinking, snubber networks for inductive loads, and current-sense feedback - to prevent thermal runaway, secondary breakdown, or overvoltage failure. System-level protection must be implemented externally; BD37916STU itself provides only the fundamental switching and amplification functions defined in its absolute maximum and electrical characteristics tables.