onsemi MMBT5771

Overview

MMBT5771 from ON Semiconductor is a PNP bipolar junction transistor optimized for high-speed saturated switching at collector currents up to 100 mA, with V_CEO = −15 V, I_C = −200 mA continuous, and t_on/t_off ≤ 15/20 ns. It serves as a compact, low-power switching amplifier in digital logic interfaces and signal-level control circuits.

For engineers reviewing the MMBT5771 datasheet, pinout, applications, or equivalent options, key selection criteria include its SOT-23 package footprint, PNP polarity, −0.15 V V_CE(sat) at −1 mA/−0.1 mA drive, −4.5 V V_EBO, and 3.0 pF C_ob for fast edge handling in space-constrained designs.

Technical Context

The MMBT5771 is fabricated on Fairchild's Process 65, enabling high-speed saturation switching with low storage time (t_s = 20 ns) and tight V_CE(sat) consistency across temperature. Its PNP topology supports active-low level shifting and sink-type load control in discrete logic stages.

Designed for operation at T_J = −55°C to +150°C, it delivers stable h_FE ≥ 20 at −55°C and ≤ 120 at 25°C under −10 mA/−0.3 V conditions, with thermal resistance R_θJA = 556°C/W on FR-4 PCB - confirming suitability for thermally unmanaged consumer and industrial PCBs.

Key Specifications

Pinout & Package

SOT-23 (TO-236AB) 3-lead plastic surface-mount package with standard JEDEC outline; marked "3R" on top surface. Device orientation follows EIAJ ED-7320A: lead 1 = Emitter, lead 2 = Base, lead 3 = Collector.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC807-16 and PN2907A, the MMBT5771 offers superior high-speed performance (15 ns t_on) and lowest V_CE(sat) in SOT-23, making it optimal for compact, fast-switching digital interface circuits where thermal and timing margins are critical.

Availability

MMBT5771 is available at Aetrix Electronics and suitable for logic level shifting, digital output buffering, LED current switching, and power rail sequencing control requiring stable component supply and consistent SOT-23 sourcing.

Supply support for MMBT5771 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 (formerly Fairchild Semiconductor) is a global leader in energy-efficient semiconductor solutions, specializing in power management, analog, sensors, and discrete devices for automotive, industrial, and consumer markets.

The MMBT5771 belongs to ON Semiconductor's legacy high-speed PNP transistor family, designed specifically for saturated switching in compact digital interface and signal conditioning circuits where speed, low saturation voltage, and thermal reliability are essential.

FAQ

What is the maximum operating temperature for the MMBT5771?

The MMBT5771 has a specified junction and storage temperature range of −55°C to +150°C. Its thermal resistance R_θJA is 556°C/W on a standard FR-4 PCB, meaning it can sustain full 225 mW dissipation only at ambient temperatures well below 25°C. For reliable long-term operation in industrial environments, derating per the 1.8 mW/°C curve is required above 25°C ambient. The MMBT5771 remains functional and within specification across this full range when operated within absolute maximum ratings.

Is the MMBT5771 pin-compatible with other SOT-23 PNP transistors?

Yes, the MMBT5771 uses the standard SOT-23 pinout: lead 1 = Emitter, lead 2 = Base, lead 3 = Collector - matching JEDEC TO-236AB. This configuration is shared by many PNP SOT-23 transistors including BC807-16 and MBT3906. However, electrical parameters such as h_FE, V_CE(sat), and switching speed differ significantly; therefore, direct substitution requires verification of gain, saturation voltage, and timing requirements in the target circuit. The MMBT5771 is not a drop-in replacement for all SOT-23 PNP parts without design validation.

What is the typical V_CE(sat) of the MMBT5771 at 10 mA collector current?

The MMBT5771 specifies V_CE(sat) = −0.18 V maximum at I_C = −10 mA and I_B = −1.0 mA, with typical values near −0.15 V under those conditions. This low saturation voltage ensures minimal power loss and heating during on-state operation, especially important in battery-powered or thermally constrained applications. The MMBT5771 achieves this performance due to its Process 65 fabrication and optimized doping profile, distinguishing it from general-purpose PNP transistors with higher V_CE(sat).

Can the MMBT5771 be used in linear amplifier configurations?

The MMBT5771 is explicitly characterized and optimized for saturated switching - not linear amplification. While its h_FE ranges from 35 to 120, small-signal gain h_fe is only specified at 8.5 @ −10 mA/−10 V/100 MHz, and no linearity, distortion, or frequency-response data is provided. Its design prioritizes fast turn-on/turn-off and low storage time, not gain flatness or harmonic suppression. For linear amplification, dedicated NPN/PNP RF or audio transistors with full AC parameter characterization should be selected instead of the MMBT5771.

Does the MMBT5771 have built-in ESD protection?

No, the MMBT5771 does not include integrated ESD protection diodes. Its absolute maximum ratings specify V_EBO = −4.5 V and V_CEO = −15 V, but these reflect intrinsic junction breakdown limits - not rated ESD immunity. Per the datasheet, handling and PCB layout must follow standard ESD precautions: use grounded workstations, anti-static packaging, and consider external series resistors or TVS clamps on base and collector lines in high-risk environments. The MMBT5771 relies entirely on external protection; its robustness against ESD events is not guaranteed beyond human-body-model (HBM) levels typical of bare silicon.