onsemi 2N3906RL1

Overview

2N3906RL1 from ON Semiconductor is a PNP bipolar junction transistor (BJT) designed for general-purpose amplification and switching at collector currents from 10 mA to 100 mA. It features a −40 V collector-emitter breakdown voltage, −200 mA continuous collector current rating, and DC current gain (h_FE) ranging from 60 to 300 depending on bias conditions. It is commonly used in low-power signal inversion, level shifting, and discrete logic interface circuits.

For engineers reviewing the 2N3906RL1 datasheet, pinout, applications, or equivalent options, key selection criteria include its TO-92 package thermal resistance (R_θJA = 200 °C/W), saturation voltage (V_CE(sat) = −0.25 V at I_C = −10 mA / I_B = −1.0 mA), and noise figure (4.0 dB at 10 Hz–15.7 kHz), especially in analog front-end and battery-powered control stages.

Technical Context

This PNP BJT operates in active, saturation, and cutoff regions with verified switching performance: delay time (t_d) and rise time (t_r) each 35 ns, storage time (t_s) 225 ns, and fall time (t_f) 75 ns under V_CC = −3.0 V, I_C = −10 mA, and I_B1 = I_B2 = −1.0 mA conditions. Its small-signal characteristics include f_T = 250 MHz at I_C = −10 mA and V_CE = −20 V, with input capacitance (C_ibo) of 10.0 pF and output capacitance (C_obo) of 4.5 pF.

The device supports operation across −55 °C to +150 °C junction temperature range and exhibits stable h_FE variation over temperature - typical pulsed current gain remains ≥100 at 25 °C and ≥60 at 125 °C for I_C = −10 mA. Its base-emitter on voltage (V_BE(ON)) ranges from 0.65 V to 0.95 V depending on collector current and temperature.

Key Specifications

Pinout & Package

2N3906RL1 is packaged in JEDEC TO-92, a through-hole 3-lead molded plastic case with straight leads. The package provides mechanical robustness and adequate thermal dissipation for low-to-medium power applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBT3906, 2N3906RL1 offers 78% higher power dissipation and lower thermal resistance, making it preferable for through-hole prototyping and higher-current switching. Versus BC557, it trades slightly lower guaranteed h_FE for broader industry availability and tighter noise performance.

Availability

2N3906RL1 is available at Aetrix Electronics and suitable for discrete amplifier design, analog signal conditioning, and low-speed digital interface applications requiring stable component supply and long-term manufacturability.

Supply support for 2N3906RL1 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 manufacturer specializing in energy-efficient power management, analog, sensors, and connectivity solutions for automotive, industrial, and consumer markets.

The 2N3906RL1 belongs to ON Semiconductor's legacy general-purpose bipolar transistor product line, originally developed by Fairchild and optimized for cost-sensitive, high-reliability discrete signal amplification and switching in non-critical applications.

FAQ

What is the pin configuration of the 2N3906RL1?

The 2N3906RL1 uses the standard TO-92 package with Emitter–Base–Collector (E-B-C) pinout when viewed from the flat side with leads pointing downward. Pin 1 is Emitter, Pin 2 is Base, and Pin 3 is Collector. This matches JEDEC TO-92 mechanical specification and is consistent across all 2N3906 variants including 2N3906RL1.

Does the 2N3906RL1 support operation at elevated temperatures?

Yes, the 2N3906RL1 is rated for junction temperatures from −55 °C to +150 °C. Its absolute maximum ratings and thermal resistance (R_θJA = 200 °C/W) allow reliable operation up to +125 °C ambient in properly derated designs. Derating begins above 25 °C at 5.0 mW/°C, limiting max power dissipation to ~500 mW at 125 °C ambient.

What is the typical noise figure of the 2N3906RL1 and under what conditions is it measured?

The 2N3906RL1 has a typical noise figure of 4.0 dB, measured at I_C = −100 μA, V_CE = −5.0 V, R_S = 1.0 kΩ, and frequency range 10 Hz to 15.7 kHz. This value reflects its suitability for low-noise preamplification in audio and sensor signal chains where minimal added noise is critical.

Can the 2N3906RL1 be used as a direct replacement for the original Fairchild 2N3906?

Yes, the 2N3906RL1 is a direct functional and pinout-compatible replacement for the legacy Fairchild 2N3906. Following ON Semiconductor's integration of Fairchild, the part retains identical electrical specifications, TO-92 packaging, and E-B-C pinout. No PCB or schematic changes are required for migration.

What are the key switching performance metrics for the 2N3906RL1?

The 2N3906RL1 delivers t_d = 35 ns, t_r = 35 ns, t_s = 225 ns, and t_f = 75 ns under V_CC = −3.0 V, I_C = −10 mA, and I_B1 = I_B2 = −1.0 mA test conditions. These values confirm suitability for digital logic interfacing and PWM-based dimming/control up to ~500 kHz with controlled edge rates.