onsemi BC487

Overview

BC487 from ON Semiconductor is an NPN silicon general-purpose high-current transistor in TO-92 package, rated for 60 V_CEO, 500 mA continuous collector current, and 625 mW power dissipation at T_A = 25°C. It delivers h_FE of 40–260 (BC487B variant), V_CE(sat) ≤ 0.5 V at I_C = 500 mA/I_B = 50 mA, and f_T = 200 MHz - used in low-voltage switching and linear amplification stages of power supplies, relay drivers, and LED ballasts.

For engineers reviewing the BC487 datasheet, pinout, applications, or equivalent options, this page provides verified electrical parameters, thermal behavior, TO-92 terminal mapping, real-world use scenarios, and validated alternative transistors for discrete BJT replacement in industrial control, automotive body electronics, and consumer appliance circuits.

Technical Context

The BC487 operates as a medium-power NPN bipolar junction transistor with fixed gain structure optimized for DC switching and Class-A/AB amplification. Its safe operating area (SOA) is defined by thermal limit (1.5 W @ T_C = 25°C), second breakdown, and current limit curves - supporting robust operation under pulsed loads up to 100 ms.

It features low base-emitter saturation voltage (V_BE(sat) ≤ 1.2 V at I_C = 1.0 A/I_B = 100 mA), 7.0 pF output capacitance (C_ob), and 50 pF input capacitance (C_ib), enabling fast turn-on/off times (t_r = 3.0 ns typical) in driver applications where gate charge minimization is not required but speed matters.

Key Specifications

Pinout & Package

BC487 is housed in TO-92 (Case 29, Style 17), a through-hole plastic package with 3 leads, bent or straight lead options, and tape-and-reel availability for BC487BRL1. Package dimensions conform to JEDEC TO-226 standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN transistor applications.

Compared with BC337-40 and 2N3904, BC487 offers superior voltage headroom (60 V vs. 45/40 V) and current capability (500 mA vs. 500/200 mA), making it the preferred choice for industrial 24–48 V DC switching where reliability under sustained load matters most.

Availability

BC487 is available at Aetrix Electronics and suitable for relay drivers, LED current sinks, DC motor controls, and audio preamplifiers requiring stable component supply across long-life industrial programs.

Supply support for BC487 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 focused on energy-efficient electronics, delivering power management, analog, sensor, and connectivity solutions.

The BC487 belongs to the BC4xx family of general-purpose NPN transistors designed for cost-sensitive, medium-current discrete switching and amplification in automotive, industrial, and consumer equipment.

FAQ

What is the maximum collector current rating for BC487?

The BC487 is rated for 500 mA continuous collector current (I_C) at T_A = 25°C. Derating applies above 25°C at 5.0 mW/°C. At elevated ambient temperatures or with limited PCB copper, actual usable current drops significantly - e.g., ~350 mA at 70°C ambient with standard FR-4 layout. Always verify thermal performance using R_JA = 200 °C/W in your specific board configuration.

Is BC487 pin-compatible with BC547?

Yes, BC487 and BC547 share identical TO-92 pinout (Collector-Base-Emitter on pins 1-2-3) and mechanical footprint. However, BC487 has higher V_CEO (60 V vs. 45 V), higher I_C (500 mA vs. 100 mA), and lower h_FE minimum (40 vs. 110), so direct substitution is safe only if voltage/current requirements exceed BC547's limits - not as a blind drop-in for gain-critical circuits.

What is the typical f_T value for BC487 and how does it affect switching performance?

The BC487 has a typical current-gain bandwidth product (f_T) of 200 MHz at I_C = 50 mA, V_CE = 2.0 V. This supports fast switching with rise/fall times around 3 ns, making it suitable for PWM frequencies up to ~500 kHz in saturated mode. However, its relatively high C_ib (50 pF) limits high-speed linear use - best applied in <10 MHz digital switching or audio-band amplification.

Does BC487 have built-in ESD or overvoltage protection?

No, BC487 has no integrated ESD protection diodes or clamp structures. Its absolute maximum V_EBO is only 5.0 V, making the base-emitter junction highly vulnerable to static discharge. External 10 kΩ base resistor and optional 5.1 V Zener from base to emitter are recommended in automated handling or field-deployed environments to prevent latent damage.

What is the difference between BC487 and BC487B variants?

The BC487B is a higher-gain version of BC487: h_FE ranges from 60–400 (vs. 40–260 for BC487) at I_C = 100 mA/V_CE = 2 V. Both share identical voltage, current, power, and thermal ratings. BC487BRL1 denotes the tape-and-reel packaging option (2000 units/reel) for automated assembly - electrically identical to bulk BC487B.