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In choosing a suitable switching transistor: The transistor’s maximum collector current must be greater than the load current. The transistor’s maximum current gain must be at least 5 times the load current divided by the maximum output current from the IC.
How do you select an equivalent transistor?
Step by step instructions: Choose a transistor of the same polarity: The first major selection criterion is whether the transistor is PNP or NPN. Select a replacement transistor of the same material: Most transistors are either silicon or germanium.
Does it matter what transistor i use?
For most general purpose transistor applications we need devices which are non-conducting with zero bias on the control input (base or gate). Such devices are BJTs or enhancement mode MOSFETs. But do we need a BJT or a MOSFET? In many cases it does not matter.
What are the requirements of a good transistor?
Ideally the transistor should be operated with a good margin in hand. Often the maximum voltage should only be allowed to rise to 50 or 60% of the maximum value for reliable operation. Note that for circuits using inductors in the collector circuit, the collector voltage may rise to twice the rail voltage.
What are specifications of transistors?
What are the specifications of transistors? Maximum collector dissipation (P C ) is the maximum value of power dissipated in collector of a transistor. Transistor frequency at which the common emitter forward current gain is unity and denoted by F T .
Can we replace NPN transistor with PNP?
Generally, the PNP transistor can replace NPN transistors in most electronic circuits, the only difference is the polarities of the voltages, and the directions of the current flow. PNP transistors can also be used as switching devices and an example of a PNP transistor switch is shown below.
What can I use instead of BC547 transistor?
BC547 Transistor Equivalent BC547 transistor can be used as an alternative to many transistors: BC548, BC549, BC636, BC639, 2N2222 TO-92, 2N2222 TO-18, 2N2369, 2N3055 and 2N3904 all are BC547 transistor equivalent.
What is BC547 transistor?
BC547 is a Bipolar Junction Transistor, abbreviated as BJT. It is an NPN transistor. It has three terminals named as: Emitter. Collector.
Can diode be used to replace a transistor?
Yes, so called the tunnel diode can and is used in place of Transistor. It has one part of a curve where there is a negative resistance ( increase of a voltage decrease of a current ).
Does transistor have resistance?
there is no “the resistance” of a transistor. A transistor isa three terminal device, so it has multiple places where there may be effective resistance.
How do you know if a transistor is NPN or PNP?
Connect the positive lead of the multimeter to the Base (B) of the transistor and connect the negative lead to the Emitter (E) of the transistor. If it is an NPN transistor then meter should show a voltage drop between 0.45V and 0.9V. If it is a PNP transistor, then it should display see “OL” (Over Limit).
How much current can a transistor handle?
Some transistors may only be rated for a maximum of 10-100mA of current to flow through them. If you supply a current over the maximum rating, the transistor might blow up.
How do you wire up a transistor?
Ground the emitter to the negative power rail. To function, your circuit will need to be grounded. Poke 1 end of the wire through a breadboard hole near your transistor and wrap it around the emitter wire 2-3 times. Then, stick the other end of the wire in a breadboard hole connected to the negative power rail.
How are transistor rated?
Power dissipation Just like resistors, transistors are rated for how many watts each can safely dissipate without sustaining damage. High temperature is the mortal enemy of all semiconductor devices, and bipolar transistors tend to be more susceptible to thermal damage than most.
How do you check if transistor is working using multimeter?
Hook the positive lead from the multimeter to the to the BASE (B) of the transistor. Hook the negative meter lead to the EMITTER (E) of the transistor. For an good NPN transistor, the meter should show a voltage drop between 0.45V and 0.9V. If you are testing PNP transistor, you should see “OL” (Over Limit).
Why use a MOSFET instead of a transistor?
MOSFET is used where high swithiching frequency operation are required because MOSFET gives low switching losses. MOSFET is a field-effect device which requires very little power to its controlling terminal i.e. gate to operate (switch the transistor ON or OFF).
What are PNP transistors used for?
PNP transistors are used to source current, i.e. current flows out of the collector. PNP transistors are used as switches. These are used in the amplifying circuits. PNP transistors are used when we need to turnoff something by push a button.
How PNP transistor works as a switch?
For a PNP transistor, the Emitter potential must be positive with respect to the Base. Then the transistor operates as a “single-pole single-throw” (SPST) solid state switch. With a zero signal applied to the Base of the transistor it turns “OFF” acting like an open switch and zero collector current flows.
How use BC547 transistor as a switch?
TRANSISTOR AS A SWITCH It just bypasses the signal present of the collector while having active base condition. As soon as we press the button a signal (in form of voltage and current) will be received by the base of BJT which in turn allows electric current to pass from collector to emitter.
What is the price of BC547 transistor?
Compare similar products from other sellers ₹ 0.50/ Piece ₹ 58/ Piece Maximum Power Dissipation 200 mW – Mounting Type Surface Mount – Pin Count 6 – Transistor Type NPN -.
Is BC547 same as 2N3904?
Both are NPN Transistors. Their difference is manufacturer and hFE and datasheet parameters, seriously. BC547 is European transistor while 2N3904 is American transistor. Both are common NPN bipolar junction transistors used for general-purpose low-power amplifying or switching applications.
