Features / technical specifications:
- Package Type: TO-92
- Transistor Type: N Channel JFET
- Max Voltage Applied From Drain to Source: 30V
- Max Drain to Gate Voltage Should Be: 30V
- Max Reverse Gate to Source Voltage is: –30V
- Max Continues Drain Current is: 25mA
- Minimum to Maximum Gate to Source Cuttoff Voltage : -0.5 to –0
- Max Power Dissipation is: 300mW
- Max Storage & Operating temperature Should Be: -55 to 150 Centigrade
- Low Noise & High Gain
Replacement and Equivalent:
BF245 can be replaced with BF245B, BF245C, 2N5457, 2SK117, MPF102, 2N5458, BF244A, BF256A, NTE457, J113, 2N3819. Other nearest Possible replacements are 2N4416, NTE312, 2N5638, 2N5640, 2SK162, 2SK518 (Always check pin configuration of the transistor you are replacing with the BF245.)
BF245 Transistor Explained / Description:
BF245 is a well know JFET transistor available in TO-92 package. It is mainly designed to use as an amplifier in the VHF and UHF frequency bands and also as an audio frequency amplifier. The transistor possess high gain and low noise capabilities due to which it will perform well to amplify a very small and low gain signal (RF, Audio or any other signal) to high gain with unwanted noise filtration.
These devices are manufactured in four different types which are BF245, BF245A, BF245B and BF245C each type is slightly different from the other in Gate-Source voltage and Zero-Gate Voltage Drain Current.
The BF245 is discontinued by many manufacturers but it is still available online by some reputable stores and some suppliers are still having them in old stock but if you are unable to find it then you can also use its equivalent transistors mentioned above.
Where We Can Use it & How to Use:
BF245 transistor can be used in many applications such as mic preamplifiers, audio preamplifiers, high power audio amplifier stages, low noise audio amplifiers, RF transmitters and receivers, RF signal boosters, RF detectors, RF sensors, VHF and UHF video senders and receivers etc.
VHF Signal Amplifier
UHF Signal Amplifier
Audio amplification and preamplification
Verity of Low Level Signal Amplification
Sensor & Detector Circuits
How to Safely Long Run in a Circuit:
Electronics components can perform very well and long life if they are used wisely. To get good and long term performance from any component it is important to not use it on its maximum limits / ratings and always use a component atleast 20% below from its maximum ratings. The BF245 should also be use like that. The maximum drain-source voltage is 30V therefore stay under 24V. The drain-gate voltage should be under 24V and gate-source should be under -24. The maximum drain current is 25mA therefore do not drive load of more than 20mA. Moreover do not use or store the transistor in temperature below -55 degree centigrade and above 150 degree centigrade.