Infineon Technologies BC 818K-25 E6327

Overview

BC818K-25 E6327 from Infineon Technologies is an NPN silicon general-purpose audio-frequency transistor with V_CEO = 25 V, I_C = 500 mA, h_FE = 160–250 (at I_C = 100 mA), V_CE(sat) ≤ 0.7 V (at I_C = 500 mA), and SOT-23 package. It serves as a low-voltage switching and amplification device in automotive signal conditioning, industrial sensor interface stages, and consumer power management circuits.

For engineers reviewing the BC818K-25 E6327 datasheet, BC818K-25 E6327 pinout, BC818K-25 E6327 application, or BC818K-25 E6327 equivalent, key selection criteria include guaranteed h_FE group 25 performance across temperature, AEC-Q101 qualification for automotive use, low saturation voltage under high current, and RoHS-compliant SOT-23 packaging suitable for space-constrained PCB layouts.

Technical Context

This transistor operates in linear and saturated modes for analog amplification and digital switching. Its h_FE group 25 ensures consistent DC current gain between 160 and 250 at I_C = 100 mA and V_CE = 1 V, with usable gain maintained down to –40 °C and up to 105 °C.

The device features V_CEO = 25 V and V_CBO = 30 V ratings, enabling safe operation in 12 V and 24 V automotive supply rails. Thermal resistance R_thJS ≤ 70 K/W (SOT-23) supports continuous 500 mW dissipation at T_S ≤ 115 °C, validated per AEC-Q101 stress testing.

Key Specifications

Pinout & Package

BC818K-25 E6327 is housed in a Pb-free, RoHS-compliant SOT-23 plastic surface-mount package with standard 3-pin configuration and 1.3 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC818K-25 E6327, BC817-25 offers higher voltage rating but lacks automotive qualification, while MMBT2222ALT1G provides better thermal resistance but less predictable gain-making BC818K-25 optimal for AEC-Q101–compliant designs requiring stable h_FE and low V_CE(sat).

Availability

BC818K-25 E6327 is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC I/O modules, and medical diagnostic equipment requiring stable component supply and long-term lifecycle assurance.

Supply support for BC818K-25 E6327 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive ICs, and discrete devices, with global manufacturing and quality certification to ISO/TS 16949.

The BC817K/BC818K series targets cost-sensitive, high-reliability general-purpose switching and amplification in automotive and industrial environments, emphasizing AEC-Q101 compliance and parametric consistency.

FAQ

Is BC818K-25 E6327 pin-compatible with BC817K-25?

Yes, both share identical SOT-23 pinout (1=B, 2=E, 3=C) and mechanical footprint. However, BC818K-25 has lower V_CEO (25 V vs. 45 V) and V_CBO (30 V vs. 50 V), so substitution requires verification of voltage stress margins in the target circuit.

What is the maximum allowable base current for continuous operation?

The absolute maximum rated base current is 100 mA per datasheet. For reliable continuous operation at I_C = 500 mA, I_B should be limited to 50 mA to maintain V_CE(sat) ≤ 0.7 V and avoid thermal runaway under worst-case h_FE conditions.

Does BC818K-25 E6327 support pulsed operation beyond its DC ratings?

Yes-pulse operation up to I_CM = 1000 mA is permitted with duty cycle ≤ 2% and pulse width < 300 µs. Permissible peak power scales inversely with pulse duration, governed by R_thJS ≤ 70 K/W and junction temperature limit of 150 °C.

How does h_FE variation affect base resistor selection in switching designs?

With h_FE = 160–250 (group 25), base resistors must be sized using h_FE(min) = 160 to guarantee saturation at worst-case gain. For I_C = 500 mA, minimum I_B = 3.125 mA yields 160× gain, requiring R_B ≤ (V_GPIO − V_BE(sat)) / 3.125 mA at V_GPIO = 3.3 V.