onsemi BC848CMTF

Overview

BC848CMTF from ON Semiconductor is an NPN epitaxial silicon transistor in SOT-23 package, rated for V_CEO = 30 V, I_C = 100 mA, and h_FE = 420–800 (Class C), optimized for low-noise switching and general-purpose amplification in compact analog and digital interface circuits.

For engineers reviewing the BC848CMTF datasheet, pinout, applications, or equivalent options, key selection criteria include its 30 V V_CEO, 420–800 h_FE range, 300 MHz f_T, 3.5–6.0 pF C_ob, and SOT-23 footprint compatibility with automated assembly in space-constrained consumer and industrial PCBs.

Technical Context

This discrete NPN transistor operates as a current-controlled switch or small-signal amplifier with DC current gain spanning 420–800 at I_C = 2 mA and V_CE = 5 V. Its 300 MHz current-gain bandwidth product supports audio-frequency and low-speed digital signal handling.

Thermal resistance R_θJA is 403 °C/W on standard FR-4 PCBs, and saturation performance is characterized at two bias points: V_CE(sat) ≤ 250 mV (I_C = 10 mA, I_B = 0.5 mA) and ≤ 600 mV (I_C = 100 mA, I_B = 5 mA), enabling reliable operation across load-switching and linear-regulator feedback roles.

Key Specifications

Pinout & Package

SOT-23 3-lead plastic surface-mount package with standard lead frame geometry and JEDEC-compliant footprint (3.0 mm × 1.4 mm × 1.1 mm). Pin 1 = Base, Pin 2 = Emitter, Pin 3 = Collector.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC847CMTF and MMBT3904LT1G, BC848CMTF delivers the narrowest h_FE range (420–800) and lowest noise figure among SOT-23 NPN transistors in its voltage class, making it optimal for precision analog front-ends and production-consistent digital interfaces where gain predictability and signal integrity are prioritized.

Availability

BC848CMTF is available at Aetrix Electronics and suitable for audio preamplification, microcontroller GPIO interfacing, LED driver circuits, and power supply feedback loops requiring stable component supply, consistent h_FE binning, and SOT-23 manufacturability.

Supply support for BC848CMTF 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, high-performance silicon solutions for automotive, industrial, cloud computing, medical, and consumer electronics markets.

The BC846/BC847/BC848/BC850 family was engineered as a standardized, high-yield SOT-23 NPN transistor series for cost-sensitive, high-volume analog and digital interface applications demanding repeatable gain, low noise, and automated assembly compatibility.

FAQ

What is the maximum collector-emitter voltage rating for BC848CMTF?

The BC848CMTF has a maximum collector-emitter voltage (V_CEO) rating of 30 V. This value is specified under DC conditions at T_A = 25°C and defines the upper limit of voltage that can be safely applied between collector and emitter while keeping the base open. Exceeding this rating risks device breakdown and permanent damage. Designers must ensure operating V_CE remains below 30 V, including transient spikes, in all use cases of BC848CMTF.

What does the "C" suffix in BC848CMTF indicate?

The "C" in BC848CMTF denotes the h_FE (DC current gain) classification bin, specifying a guaranteed range of 420 to 800 at V_CE = 5 V and I_C = 2 mA. This tight binning improves predictability of base drive requirements and reduces unit-to-unit variation in production circuits using BC848CMTF. The "M" indicates SOT-23 package, and "TF" confirms tape-and-reel packaging for automated assembly.

Is BC848CMTF suitable for low-noise amplifier applications?

Yes, BC848CMTF is suitable for low-noise amplifier applications, with a specified noise figure of 2.0–10.0 dB at 1 kHz (V_CE = 5 V, I_C = 200 μA, R_G = 2 kΩ). While not as low-noise as the BC850 variant (1.2–4.0 dB), its performance supports microphone preamps, sensor signal conditioning, and other audio-frequency analog stages where moderate noise floor and gain consistency are required. Designers should verify noise performance under actual circuit bias conditions for BC848CMTF.

What is the thermal resistance (R_θJA) of BC848CMTF and how does it affect layout?

The BC848CMTF has a junction-to-ambient thermal resistance (R_θJA) of 403 °C/W on a standard FR-4 PCB (76 mm × 114 mm, minimum land pattern). This high value means even modest power dissipation (e.g., 100 mW) raises junction temperature significantly-by ~40°C above ambient. To maintain reliability, PCB layout for BC848CMTF should maximize copper area around the SOT-23 pads, avoid enclosing the device in thermally isolated zones, and consider derating power above 25°C (2.48 mW/°C).

Can BC848CMTF replace BC847CMTF in an existing design?

BC848CMTF can replace BC847CMTF only if the application operates within its lower 30 V V_CEO limit (BC847CMTF is rated for 45 V). Both share identical SOT-23 package, pinout, h_FE Class C binning, and electrical characteristics except voltage ratings. Substituting BC848CMTF into a 40 V collector circuit would risk failure. Verify V_CE stress margins first; if within 30 V, BC848CMTF offers equivalent or improved gain consistency and noise performance in the BC848CMTF implementation.