onsemi MMBT6515

Overview

MMBT6515 from Fairchild Semiconductor is an NPN general-purpose bipolar junction transistor (BJT) designed for amplification and switching in low-power analog and digital circuits, with V_CEO = 25 V, I_C = 200 mA continuous, h_FE = 250–500 at 2 mA, and f_T = 100 MHz - used in signal conditioning stages of portable audio preamps and logic-level interface drivers.

For engineers reviewing the MMBT6515 datasheet, pinout, applications, or equivalent options, key selection considerations include its SOT-23 package footprint, guaranteed h_FE range at 2 mA and 100 mA, V_CE(sat) ≤ 0.5 V at I_C/I_B = 50 mA/5 mA, thermal resistance R_θJA = 357°C/W, and ESD rating per JEDEC JS-001 Class 1B.

Technical Context

The MMBT6515 operates as a discrete NPN BJT with base-emitter forward bias enabling current-controlled collector current flow. Its DC current gain (h_FE) is specified across two operating points: 250–500 at I_C = 2.0 mA and 150–500 at I_C = 100 mA, confirming usable gain over three decades of collector current.

It supports small-signal amplification up to 100 MHz (f_T) and switching operation up to 100 mA, with V_CE(sat) = 0.5 V max under forced β = 10 conditions. Thermal performance is defined for SOT-23 mounting on FR-4 PCB (1.6″ × 0.06″), yielding R_θJA = 357°C/W and P_D = 350 mW at T_A = 25°C.

Key Specifications

Pinout & Package

SOT-23 plastic surface-mount package with gull-wing leads; marked "3J"; 1.3 mm × 2.9 mm footprint; rated for reflow soldering per J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC847B and MMBT3904, the MMBT6515 offers tighter h_FE consistency at low collector currents and verified 100 MHz f_T, making it preferable for precision biasing and mid-band RF amplification where gain predictability and bandwidth are prioritized over maximum voltage rating.

Availability

MMBT6515 is available at Aetrix Electronics and suitable for portable audio preamplifiers, microcontroller GPIO interface circuits, and low-power sensor signal conditioning requiring stable component supply and consistent h_FE performance across production lots.

Supply support for MMBT6515 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 devices before its acquisition by ON Semiconductor in 2016.

The MMBT6515 belongs to Fairchild's legacy general-purpose BJT family, engineered for cost-effective, reliable amplification and switching in consumer, industrial, and computing applications where moderate speed and gain consistency are essential.

FAQ

What is the maximum continuous collector current rating for the MMBT6515?

The MMBT6515 has a maximum continuous collector current (I_C) rating of 200 mA at T_A = 25°C. This value is derated linearly above 25°C at 2.8 mW/°C, corresponding to its 350 mW total power dissipation limit in the SOT-23 package. Exceeding this current risks thermal runaway or permanent degradation of the MMBT6515.

Does the MMBT6515 have a documented transition frequency (f_T) specification?

Yes, the MMBT6515 datasheet specifies a transition frequency (f_T) of 100 MHz. This parameter is measured under small-signal conditions and confirms the device's suitability for amplification tasks up to VHF frequencies, including audio and low-speed RF applications where the MMBT6515 is commonly deployed.

What is the pin configuration of the MMBT6515 in its SOT-23 package?

The MMBT6515 in SOT-23 uses a standardized pinout: Pin 1 is Base, Pin 2 is Emitter, and Pin 3 is Collector - marked "3J" on the package top. This matches JEDEC TO-236AB and is identical to industry-standard NPN SOT-23 transistors, ensuring compatibility with existing layout footprints for the MMBT6515.

Is the MMBT6515 suitable for switching applications, and what is its saturation voltage?

Yes, the MMBT6515 is explicitly rated for switching use, with V_CE(sat) ≤ 0.5 V specified at I_C = 50 mA and I_B = 5 mA (forced β = 10). This low saturation voltage ensures minimal power loss and heat generation when the MMBT6515 is used as a saturated switch in digital logic interfaces or LED drivers.

What is the guaranteed minimum DC current gain (h_FE) for the MMBT6515 at low collector current?

The MMBT6515 guarantees h_FE ≥ 250 at I_C = 2.0 mA and V_CE = 10 V. This tight low-current gain specification supports stable biasing in high-input-impedance amplifier stages and ensures predictable turn-on behavior in microcontroller-driven switching circuits using the MMBT6515.