BC557B – FSC

Overview

The STMicroelectronics BC557B is a general-purpose PNP bipolar junction transistor designed for amplification and switching applications. Its key operational characteristic lies in its moderate current handling capability (up to 100 mA DC collector current) and a respectable voltage rating (45 V VCEO). A critical design consideration when employing the BC557B in linear amplification stages is managing its inherent noise figure, which can become a limiting factor in low-signal front-end designs where minimizing signal degradation is paramount. This device offers a balance between performance and cost-effectiveness for numerous analog circuit implementations.

Key Features

• PNP Silicon Bipolar Junction Transistor
• Collector-Emitter Voltage (VCEO): 45 V
• Continuous Collector Current (IC): 100 mA
• DC Current Gain (hFE): 220 (minimum)
• Gain Bandwidth Product (fT): 100 MHz
• Through-Hole Mounting, TO-92-3 Package (4.95mm x 3.94mm x 4.95mm)

Applications

The component is engineered for deployment in systems requiring high reliability and performance under specific operating conditions. It provides functional stability across the stated design envelope.

• Low-frequency audio amplification stages
• General-purpose switching circuits
• Bias current generation for active filters
• Signal level shifting in discrete logic interfaces