onsemi BC182_D74Z

Overview

BC182_D74Z from Fairchild Semiconductor is an NPN general-purpose bipolar junction transistor (BJT) designed for low-power amplification and switching up to 100 mA collector current. It features V_CEO = 50 V, V_CBO = 60 V, h_FE = 40–500 (at IC = 10 µA to 100 mA), f_T = 150 MHz, and TO-92 package - used in audio preamplifiers, signal buffering, and discrete logic interfaces.

For engineers reviewing the BC182_D74Z datasheet, pinout, applications, or equivalent options, key selection considerations include its DC current gain range across operating currents, saturation voltage at 100 mA, thermal dissipation limit of 350 mW at 25°C, and compatibility with through-hole PCB assembly using standard TO-92 footprints.

Technical Context

The BC182_D74Z operates as a silicon NPN BJT with planar epitaxial construction, optimized for linear amplification and medium-speed switching. Its h_FE varies significantly with collector current (40 at 10 µA, 120 at 2 mA, 80 at 100 mA), indicating intentional biasing flexibility for analog gain staging or digital on/off control.

Thermal performance is defined by R_θJA = 357°C/W and PD = 350 mW at TA = 25°C, with derating of 2.8 mW/°C above ambient - requiring attention to board copper area and airflow in sustained 100 mA operation. Cob = 5 pF and f_T = 150 MHz support RF-coupled amplifier stages up to low-VHF.

Key Specifications

Pinout & Package

BC182_D74Z is housed in a standard TO-92 plastic package with 3 leads: Collector (lead 1), Base (lead 2), Emitter (lead 3), viewed from flat side with leads down and tab up.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN general-purpose amplifier applications.

Compared with BC547B and 2N3904, BC182_D74Z offers superior V_CEO/V_CBO ratings (50 V/60 V) and broader h_FE range - making it preferable in 48 V telecom interfaces or legacy 50 V supply designs where voltage margin and gain adaptability matter more than ultra-low noise or high-speed response.

Availability

BC182_D74Z is available at Aetrix Electronics and suitable for audio preamplifiers, discrete logic level shifters, and LED/relay drivers requiring stable component supply across industrial control, instrumentation, and legacy equipment repair programs.

Supply support for BC182_D74Z 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 components before its acquisition by ON Semiconductor in 2016.

The BC182_D74Z belongs to Fairchild's legacy general-purpose BJT family, engineered for cost-sensitive, through-hole-based analog and switching functions in consumer, industrial, and educational electronics.

FAQ

What is the maximum collector-emitter voltage rating for BC182_D74Z?

The BC182_D74Z has a guaranteed V_CEO rating of 50 V at T_C = 25°C. This is the absolute maximum voltage that can be applied between collector and emitter with base open before breakdown occurs. Exceeding this value risks permanent device failure. Derating is required at elevated temperatures per the datasheet thermal curves.

Does BC182_D74Z have a specified noise figure, and under what conditions?

Yes, BC182_D74Z specifies a noise figure (NF) of 10 dB, measured at V_CE = 5 V, I_C = 0.2 mA, R_S = 2 kΩ, and f = 1 kHz. This value reflects its suitability for low-noise small-signal amplification, particularly in audio front-end stages where signal integrity at sub-mV levels is critical.

What is the pin configuration of BC182_D74Z in the TO-92 package?

When viewing the BC182_D74Z TO-92 package with the flat side facing you and leads pointing downward, the pin order from left to right is: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter. This configuration is standardized across Fairchild's BC182 series and matches JEDEC TO-92 outline drawings.

Can BC182_D74Z be used as a direct replacement for BC547 in existing designs?

BC182_D74Z is not a direct replacement for BC547 due to differences in h_FE range (BC182_D74Z: 40–500; BC547: 110–800) and V_CEO (50 V vs. 45 V). While both are TO-92 NPN transistors, circuit performance may vary - especially in bias-sensitive amplifier stages. Verify operating point stability and saturation margins before substitution.

What is the thermal dissipation limit of BC182_D74Z at room temperature?

The BC182_D74Z has a total device dissipation (P_D) limit of 350 mW at ambient temperature (T_A) = 25°C. Above 25°C, power must be linearly derated by 2.8 mW/°C. This limit assumes free-air convection; PCB copper area and airflow significantly affect real-world thermal performance.