Question 1

What are the key features of STMicroelectronics BC857B?

EZKEY · Accepted Answer

This product belongs to the Bipolar Transistors - BJT category and ships in standard packaging. It features high reliability, stable performance and low power consumption. Key parameters include wide operating range, low loss, and over-temperature protection, suitable for industrial applications. Manufactured by STMicroelectronics with full traceability.

Question 2

What are the main application scenarios for BC857B?

EZKEY · Accepted Answer

Typical applications include power management, industrial control. Additionally, it is widely used in automotive electronics, telecom infrastructure, medical devices, and consumer electronics as a critical circuit component, improving system integration and energy efficiency.

Question 3

How does BC857B work?

EZKEY · Accepted Answer

This device follows established Bipolar Transistors - BJT design principles. Core functional stages include input handling, signal and power processing, and protection logic, ensuring stable operation under varying conditions. Refer to the datasheet for the detailed characteristics and application guidance.

Question 4

What is the technical performance of BC857B?

EZKEY · Accepted Answer

Performance highlights: stable characteristics across the operating temperature range, low loss, and long service life. Reliable contact and shock resistance, with protection against over-current and over-voltage where applicable. Meets industrial and automotive reliability standards where the series qualifies.

Question 5

What is the current market demand for BC857B?

EZKEY · Accepted Answer

The global Bipolar Transistors - BJT market is growing at ~6-8% CAGR, with particularly strong demand in power management. STMicroelectronics BC857B is a mainstream model with stable stock and a typical lead time of 2-4 weeks. Driven by new energy and smart electronics trends, inquiries for this model are steadily increasing, indicating a positive long-term outlook.

Question 6

What are the technical characteristics of BC857B?

EZKEY · Accepted Answer

Three main technical features: 1) High reliability – stable performance over the rated life; 2) Low-loss design – reduced energy loss in operation; 3) Wide adaptability – compatible with various operating conditions. Additionally, STMicroelectronics provides full technical support and reference designs.

Collector Current	100 mA
Collector Emitter Saturation Voltage	0.2 V max
Configuration	Single
Emitter Base Voltage	5 V
Hfe	hFE 200-450
Mounting Style	Surface Mount
Noise Figure	5 dB typical
Package Type	SOT-23
Polarity	PNP
Power Dissipation	350 mW
Temperature Range	-65 to +150 C
Transistor Type	BJT
Transition Frequency	300 MHz
Vceo	45 V

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BC857B | STMicroelectronics TRANSISTOR PNP -45V -100MA SOT23

Product Details

PDF Datasheet

Technical Docs

Technical Parameters

BC857B Application and Selection Guide

BC857B Model and Manufacturer Information

BC857B Product Parameters and Description

BC857B Application and Selection Reference

Recommended Part Numbers for BC857B