onsemi BC182A

Overview

BC182A from ON Semiconductor is an NPN silicon small-signal amplifier transistor in TO-92 package, rated for V_CEO = 50 V, I_C = 100 mA, P_D = 350 mW at T_A = 25°C, with h_FE = 120–500 (at I_C = 2.0 mA, V_CE = 5.0 V), used in audio preamplifier stages and low-power switching circuits.

For engineers reviewing the BC182A datasheet, pinout, applications, or equivalent options, key selection criteria include DC current gain spread across variants, saturation voltage performance at 100 mA, thermal resistance (R_JA = 357 °C/W), and Pb-free TO-92 compatibility for legacy board rework and industrial control signal conditioning.

Technical Context

The BC182A operates as a general-purpose NPN bipolar junction transistor optimized for linear amplification and low-speed switching. Its h_FE range (120–500) and f_T = 150 MHz (typ.) support mid-band audio and sensor interface applications where gain stability and noise figure (NF = 2.0 dB typ. at I_C = 0.2 mA) are critical.

It shares the same TO-92 package and pinout (Collector–Base–Emitter, Pin 1–2–3) with BC182 and BC182B but differs in guaranteed h_FE min/max bins: BC182A specifies h_FE ≥120 (I_C = 2.0 mA), while BC182B guarantees ≥180 and BC182 ≥40. V_CE(sat) ≤0.25 V at I_C/I_B = 100 mA/5 mA confirms suitability for saturated-switching roles.

Key Specifications

Pinout & Package

BC182A uses the industry-standard TO-92 (Case 29, Style 17) plastic package with 3 leads, designed for through-hole mounting and manual soldering. Package dimensions comply with ANSI Y14.5M and are fully compatible with legacy PCB footprints for BC182-series transistors.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN small-signal amplifier applications.

Compared with BC547B and 2N3904, the BC182A offers superior V_CEO margin (50 V) and lower noise (2.0 dB) for precision analog front-ends, while maintaining full TO-92 footprint compatibility-making it ideal for industrial upgrades of legacy BC182 designs requiring improved gain consistency.

Availability

BC182A is available at Aetrix Electronics and suitable for audio preamplifiers, sensor signal conditioners, and relay driver circuits requiring stable component supply, long-lifecycle availability, and RoHS-compliant through-hole assembly.

Supply support for BC182A 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

ON Semiconductor (now onsemi) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The BC182A belongs to the BC182 family of general-purpose NPN transistors engineered for reliability in legacy industrial controls, audio equipment, and instrumentation where proven performance and long-term availability outweigh cutting-edge specs.

FAQ

What is the maximum collector-emitter voltage rating for BC182A?

The BC182A has a maximum collector-emitter voltage (V_CEO) rating of 50 Vdc. This value is tested under specified conditions (I_C = 2.0 mA, I_B = 0) and represents the absolute maximum voltage that can be applied between collector and emitter before breakdown occurs. Exceeding this rating risks permanent device failure, and design margins should account for transient spikes and temperature derating.

Does BC182A have a guaranteed minimum h_FE at 100 mA collector current?

No-the BC182A datasheet specifies h_FE min/max only at I_C = 2.0 mA (120–500) and I_C = 100 mA (80–220) for the BC182 variant. At 100 mA, BC182A's h_FE is not binned; designers should use the BC182B variant if guaranteed h_FE ≥180 at 100 mA is required. Always consult the latest onsemi BC182/D datasheet for test conditions.

Is BC182A pin-compatible with BC182 and BC182B?

Yes-BC182A shares identical TO-92 package (Case 29, Style 17) and pinout (Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter) with BC182 and BC182B. No PCB layout changes are needed when substituting within the same family, though h_FE and V_CE(sat) performance differ across variants and must be verified per circuit requirements.

What is the thermal resistance (R_JA) of BC182A, and how does it affect PCB layout?

The BC182A has a junction-to-ambient thermal resistance (R_JA) of 357 °C/W under standard JEDEC test conditions. This high value means even modest power dissipation (e.g., 100 mW) causes >35°C junction rise above ambient. To maintain reliability, minimize copper pour isolation around the TO-92 pad, avoid enclosing the device in sealed enclosures, and consider derating power above 25°C ambient per the 2.8 mW/°C spec.

Can BC182A be used in low-noise audio applications?

Yes-the BC182A achieves a typical noise figure (NF) of 2.0 dB at I_C = 0.2 mA, V_CE = 5.0 V, R_S = 2.0 kΩ, and f = 1.0 kHz, making it suitable for low-level audio preamplifier stages. For optimal noise performance, bias the device near its 0.2 mA sweet spot, use low-noise carbon composition or metal film resistors in the base network, and shield the input node from digital noise sources.