onsemi BC33825BU

Overview

BC33825BU from ON Semiconductor is an NPN epitaxial silicon transistor in TO-92 package, rated for 25 V V_CEO, 800 mA I_C, and 625 mW power dissipation, with h_FE of 160–400 at I_C = 100 mA, used in low-power switching and AF-driver stages.

For engineers reviewing the BC33825BU datasheet, pinout, applications, or equivalent options, key selection criteria include its 25 V collector-emitter breakdown voltage, 160–400 DC current gain range, TO-92 3-lead package compatibility, and suitability for general-purpose amplification and switching in cost-sensitive consumer and industrial circuits.

Technical Context

The BC33825BU operates as a general-purpose NPN bipolar junction transistor optimized for linear amplification and saturated switching. Its design supports V_CE = 1 V, I_C = 100 mA test conditions for h_FE classification and delivers V_CE(sat) ≤ 0.7 V at I_C = 500 mA / I_B = 50 mA.

Thermal performance is defined by R_θJA = 200 °C/W on standard FR-4 PCB (76 mm × 114 mm), with maximum junction temperature of 150 °C and storage range from –55 °C to +150 °C - enabling use in ambient environments up to 75 °C at full rated power.

Key Specifications

Pinout & Package

BC33825BU uses the industry-standard TO-92 3-lead plastic package with straight leads and bulk packing. Pin 1 is Collector, Pin 2 is Base, Pin 3 is Emitter - verified per JEDEC TO-92 outline and Fairchild/ON Semiconductor mechanical drawings.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC33825TA and BC33725BU, the BC33825BU offers optimal balance of voltage rating, gain consistency, and cost for 24 V-class switching and amplification - avoiding over-specification while maintaining reliability in standard consumer-grade PCB environments.

Availability

BC33825BU is available at Aetrix Electronics and suitable for audio pre-amplifiers, relay drivers, low-power output stages, and LED current switches requiring stable component supply and long-term manufacturability.

Supply support for BC33825BU 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 is a global semiconductor supplier delivering energy-efficient power and signal management solutions, with roots in Fairchild Semiconductor's legacy analog and discrete portfolio.

The BC33825BU belongs to the BC337/BC338 family of general-purpose NPN transistors designed for cost-sensitive, high-volume applications in consumer electronics, industrial controls, and automotive body electronics - emphasizing robustness, repeatability, and ease of integration.

FAQ

What is the maximum collector-emitter voltage rating for BC33825BU?

The BC33825BU has a maximum collector-emitter voltage (V_CEO) rating of 25 V under open-base conditions at T_A = 25 °C. This value is confirmed in the Absolute Maximum Ratings table of the official ON Semiconductor datasheet for BC337/BC338 Rev. 1.5. Exceeding this voltage risks avalanche breakdown and permanent device failure. Designers should maintain ≥20% derating margin for reliability in variable-temperature environments. The BC33825BU is not rated for 30 V or higher rail applications.

Does BC33825BU have a specified h_FE range, and how is it binned?

Yes, the BC33825BU is binned to the "25" h_FE classification, guaranteeing a DC current gain (h_FE1) of 160–400 when measured at V_CE = 1 V and I_C = 100 mA. This binning is explicitly defined in the Electrical Characteristics table of the BC337/BC338 datasheet. The "25" suffix directly corresponds to this gain range - distinct from BC33816BU (100–250) and BC33840BU (250–630). No additional h_FE tolerance or statistical spread is specified beyond this range.

What package type and lead configuration does BC33825BU use?

The BC33825BU uses the JEDEC-standard TO-92 3-lead plastic package with straight leads and bulk packing. Pin 1 is Collector, Pin 2 is Base, Pin 3 is Emitter - matching the mechanical drawing in Figure 1 of the BC337/BC338 Rev. 1.5 datasheet. It is not supplied in tape-and-reel or ammo formats; those variants carry suffixes like "TFR" or "TA". The TO-92 outline ensures compatibility with standard through-hole PCB footprints and manual soldering processes.

Can BC33825BU be used as a direct replacement for BC33725BU?

No, BC33825BU is not a direct replacement for BC33725BU due to differing V_CEO ratings: BC33825BU is rated for 25 V, while BC33725BU supports 45 V. Although both share identical h_FE, I_C, package, and pinout, substituting BC33825BU in a 45 V circuit risks premature breakdown. The BC33825BU is intended for 24 V or lower systems; BC33725BU remains necessary where higher voltage headroom is required. Always verify supply rail margins before interchange.

What is the thermal resistance and power derating behavior of BC33825BU?

The BC33825BU has a junction-to-ambient thermal resistance (R_θJA) of 200 °C/W on a standard FR-4 PCB (76 mm × 114 mm). Its power dissipation is rated at 625 mW at 25 °C ambient, with linear derating of 5.0 mW/°C above that temperature. This means usable power drops to zero at 150 °C case temperature (25 °C + 625 mW / 5 mW/°C). The BC33825BU's 150 °C maximum junction temperature is fully leveraged only with adequate board copper and airflow - no heatsink is integrated or required.