BF245 Transistor Guide: Pinout, Datasheet, and Replacements

In this article, we dig into the intricacies of the BF245 N-channel silicon field-effect transistor from ON Semiconductor, packaged in the versatile TO-92 form. Designed for signal amplification across VHF, UHF, and audio frequency applications, the BF245 series, including variants like BF245A, BF245B, and BF245C, is known for its high gain and low noise performance. This article explores the BF245's pin configuration, specifications, and substitute options, helping you understand its unique characteristics and how it stands out in signal processing. Whether you're considering substitutes, configuring pins, or examining CAD specifications, this guide offers a thorough analysis for effective use in various electronics applications.

Catalog

BF245 Overview

The BF245 is primarily utilized for amplifying signals within VHF, UHF bands, and audio frequencies. With high gain and low noise attributes, it adeptly amplifies small signals while minimizing noise interference.

The series, including BF245, BF245A, BF245B, and BF245C, shows distinct electrical characteristics, mostly in gate-source voltage and zero-gate voltage drain current. These differences cater to specific applications, offering versatility in optimizing circuit designs for diverse signal amplification needs. Efficacy in VHF and UHF bands is remarkable due to their ability to manage and amplify weaker signals, enhancing signal clarity and strength, basic for broadcasting and communication systems.

In audio frequency applications, the BF245 excels by preserving signal integrity and minimizing distortion, used in high-fidelity audio equipment. Its ability to filter out noise ensures cleaner audio output. Compared to similar transistors, the BF245's balance between high gain and low noise makes it a popular choice. You can often prefer this component for its robustness and reliability in demanding environments.

Pin Configuration

PIN	SYMBOL	DESCRIPTION
1	g	Gate
2	s	Source
3	d	Drain

BF245 CAD Specifications

Symbol

Footprint

3D Model

Features

Feature	Specification
Package Type	TO-92
Transistor Type	N Channel JFET
Drain-Source Voltage	30V (Maximum)
Drain-Gate Voltage	30V (Maximum)
Reverse Gate-Source Voltage	–30V (Maximum)
Continuous Drain Current	25mA (Maximum)
Gate-Source Cutoff Voltage	-0.5V to –0V
Power Dissipation	300mW (Maximum)
Storage & Operating Temperature	-55°C to +150°C
Noise Level & Gain	Low Noise & High Gain
Operating Frequency	Up to 700 MHz
Drain and Source Interchangeability	Yes

Technical Specification

Here is the technical specification table for the ON Semiconductor BF245B JFET.

Type	Parameter
Lifecycle Status	Obsolete
Last Shipments	Last Updated: 1 week ago
Mount	Through Hole
Package / Case	TO-226-3, TO-92-3 (TO-226AA)
Number of Pins	3
Weight	200 mg
Breakdown Voltage / V	-30 V
Number of Elements	1
Packaging	Bulk
Published	2009
JESD-609 Code	e0
Pbfree Code	No
Part Status	Obsolete
Moisture Sensitivity Level (MSL)	1 (Unlimited)
Number of Terminations	3
ECCN Code	EAR99
Terminal Finish	Tin/Lead (Sn/Pb)
Max Operating Temperature	150°C
Min Operating Temperature	-55°C
HTS Code	8541.21.00.75
Voltage - Rated DC	30 V
Current Rating (Amps)	100 mA
Max Power Dissipation	350 mW
Terminal Position	Bottom
Peak Reflow Temperature (°C)	240
Reach Compliance Code	Not Compliant
Current Rating	10 mA
Time@Peak Reflow Temp-Max (s)	30
Base Part Number	BF245
Pin Count	3
Qualification Status	Not Qualified
Element Configuration	Single
Operating Mode	Depletion Mode
Power Dissipation	350 mW
Transistor Application	Amplifier
Drain to Source Voltage (Vdss)	15 V
Transistor Type	N-Channel JFET
Continuous Drain Current (ID)	15 mA
Gate to Source Voltage (Vgs)	-30 V
Drain Current-Max (Abs) (ID)	0.1 A
Drain to Source Breakdown Voltage	30 V
FET Technology	Junction
Highest Frequency Band	Ultra High Frequency B
Height	4.58 mm
Length	4.58 mm
Width	3.86 mm
RoHS Status	Non-RoHS Compliant
Lead Free	Lead Free

Replacement of BF245

• BF245C

• 2N5457

• 2SK117

• MPF102

• 2N5458

• BF244A

• BF256A

• J113

• 2N3819

• 2N4416

• 2N5638

• 2SK162

Applications

VHF and UHF Signal Amplification

The BF245 finds extensive use in amplifying VHF (Very High Frequency) and UHF (Ultra High Frequency) signals. These frequencies play a role in radio communication, television broadcasting, and wireless devices, requiring detailed amplification to maintain signal clarity. You can explore into sophisticated configurations to enhance performance, contemplating challenges like signal distortion and noise management. This pursuit often aligns with the emotional satisfaction of achieving technical excellence.

RF Oscillators

This transistor plays a part in crafting RF oscillators, which generate stable and precise frequency signals. Its low noise feature enriches the quality of output signals, a factor cherished in telecommunications and broadcasting circles. You can invest the emotional and intellectual effort to minimize harmonic distortion while preserving frequency stability, drawing insights from hands-on experiences to adjust circuit parameters.

Audio Amplification

In the domain of audio amplification, the BF245 provides dependable support for low-power audio signals. Its role in audio circuits ensures minimal distortion, making it suitable for high-fidelity audio systems. The art of balancing power consumption with performance becomes an exact task, you can enjoy refining to enhance the listening experience, informed by practical expertise in correctly biasing the transistor.

Low-Level Signal Processing

For low-level signal processing, often seen in analytical and measurement instruments, the BF245 demonstrates its worth. Handling weak signals adeptly ensures data integrity. Working with this transistor in fields such as environmental monitoring and biomedical engineering becomes an exploration of customizing circuits to meet precise measurement needs, enjoying the intellectual engagement this entails.

Sensor Circuits

The BF245 enhances sensor circuits by amplifying weak signals from diverse sensors. Whether in temperature, pressure, or humidity sensing, this transistor provides stable amplification, facilitating accurate sensor data interpretation. You can seek to refine sensor circuits, focusing on minimizing response times and enhancing sensitivity, all while appreciating the BF245’s consistent performance across different conditions.

Package

Manufacturer

ON Semiconductor serves the semiconductor sector with a diverse array of products. The company specializes in power and signal management, logical components, and discrete and tailored devices like automotive, communications, computing, consumer, industrial, LED lighting, medical, military/aerospace, and power applications. ON Semiconductor operates an extensive network in North America, Europe, and Asia Pacific. The company is headquartered in the vibrant city of Phoenix, Arizona, a hub that fuels its innovative spirit.

Datasheet PDF

BF245A Datasheets:

BF245A,B,C.pdf

BF245A,B.pdf

BF245B Datasheets:

BF245A,B,C.pdf

BF245A,B.pdf

BF245C Datasheets:

BF245A,B,C.pdf

MPF102 Datasheets:

MPF102.pdf

MPF102.pdf

2N5458 Datasheets:

2N5457-59, MMBF5457-59.pdf

Cylindrical Battery Holders.pdf

BF244A Datasheets:

BF244A/B/C.pdf

BF256A Datasheets:

BF256A.pdf

2N3819 Datasheets:

2N3819.pdf

2N5638 Datasheets:

2N5638.pdf