onsemi FMBSA06

Overview

FMBSA06 from Fairchild Semiconductor is an NPN general-purpose amplifier transistor in SuperSOT™-6 package, rated for 80 V V_CEO, 500 mA continuous I_C, and 100 MHz f_T, used in low-to-mid-power linear amplification and switching circuits such as audio preamplifiers and load drivers.

For engineers reviewing the FMBSA06 datasheet, pinout, applications, or equivalent options, key selection criteria include its 100–100 h_FE range at 10–100 mA, 0.25 V V_CE(sat) at I_C = 100 mA/I_B = 10 mA, thermal resistance of 180 °C/W, and operation across –55 to +150 °C junction temperature range.

Technical Context

The FMBSA06 is a silicon NPN bipolar junction transistor optimized for general-purpose linear amplification and switching up to 300 mA collector current. It features a minimum h_FE of 100 at both 10 mA and 100 mA test conditions, with V_CE(sat) tightly specified at 0.25 V under forced β = 10 drive.

Its 100 MHz f_T supports RF-capable small-signal gain at V_CE = 2.0 V and I_C = 10 mA, while V_(BR)CEO = 80 V and V_EBO = 4.0 V define safe operating limits for biasing and breakdown immunity in single-supply configurations.

Key Specifications

Pinout & Package

FMBSA06 is housed in the SuperSOT™-6 surface-mount package (6-pin, leadless, thermally enhanced), with pin #1 marked by a dot (.1G1). The package provides improved power dissipation over standard SOT-23 variants and supports automated placement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBT5551 and ZTX653, the FMBSA06 uniquely balances 500 mA current capability, 80 V rating, and SuperSOT™-6 thermal performance-making it optimal for space-constrained, medium-power surface-mount amplifier and switch designs requiring consistent h_FE and low V_CE(sat).

Availability

FMBSA06 is available at Aetrix Electronics and suitable for audio preamplifier stages, DC motor drivers, and LED constant-current sinks requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for FMBSA06 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 FMBSA06 belongs to Fairchild's SuperSOT™-6 NPN amplifier family, designed specifically for high-current-density, thermally efficient general-purpose amplification and switching in compact surface-mount systems.

FAQ

What is the maximum continuous collector current rating for the FMBSA06?

The FMBSA06 has a maximum continuous collector current rating of 500 mA at T_A = 25 °C, as specified in its Absolute Maximum Ratings table. This rating assumes proper PCB thermal management-specifically, mounting on a 1 in² pad of 2 oz copper. At elevated ambient temperatures or reduced copper area, derating is required per the R_θJA = 180 °C/W thermal resistance value. The FMBSA06 remains functional up to its 150 °C maximum junction temperature limit.

Does the FMBSA06 have a pin-compatible replacement in modern ON Semiconductor portfolios?

No direct pin-compatible replacement for the FMBSA06 exists in current ON Semiconductor portfolios. While ON Semiconductor absorbed Fairchild's product lines, the FMBSA06 remains a legacy part without a designated successor in SuperSOT™-6 NPN amplifier category. Engineers should verify layout compatibility and electrical parameters when considering alternatives like MMBT5551 or ZTX653, as neither matches the FMBSA06's dual-collector/dual-emitter structure or thermal pad configuration.

What is the significance of the NC pin (Pin 6) on the FMBSA06?

Pin 6 of the FMBSA06 is explicitly designated as NC (No Connection) in the official datasheet and must remain unconnected in circuit design. It has no internal bond wire or die connection and serves only as a mechanical alignment or thermal relief feature in the SuperSOT™-6 package. Soldering Pin 6 to ground, V_CC, or any other net may cause unpredictable behavior or violate absolute maximum ratings due to potential parasitic coupling or package stress.

Can the FMBSA06 be used in linear regulator pass transistor applications?

Yes, the FMBSA06 can serve as a pass transistor in low-dropout linear regulators, particularly where 500 mA output and 80 V input margin are sufficient. Its 0.25 V V_CE(sat) at 100 mA and stable h_FE support predictable current mirroring and error amplifier feedback. However, thermal design is critical: at full 500 mA load with 5 V dropout, power dissipation reaches ~2.5 W-exceeding the 700 mW rating-so operation must be limited to ≤200 mA unless augmented with external heatsinking or active cooling.

How does the dual-collector/dual-emitter construction affect FMBSA06 layout guidelines?

The dual-collector (Pins 3 & 4) and dual-emitter (Pins 1 & 5) configuration of the FMBSA06 requires both pins of each pair to be shorted externally on the PCB to realize full current and thermal benefits. Leaving either collector or emitter pin floating degrades current sharing, increases local heating, and risks parametric shift. Layout must ensure low-impedance copper traces between Pins 1–5 and Pins 3–4, and avoid routing sensitive signals beneath the thermal pad area to prevent noise coupling into the emitter path.