A comparison of Mosfet and Bipolar Transistor amplifiers
Ever wondered which makes the best – when it comes to build and amplifier ? A Mosfet or a Bipolar transistor ? Lets go through this article which compares both pros and cons of this dilemma. Most people in general never care about this as long as they get a satisfactory output performance.
Lets first go through some Mosfet amplifiers – thats a list of mosfet amplifier circuits for many output variations, say 10 watts, 18 watts and 50 watts. Okay! Now lets go through another list of Transistor amplifiers - which lists many amplifier circuits built using bipolar transistors. Now that should give you a rough idea and freshen up the concepts.
Lets come to the point then, we are talking about a comparison between Mosfet and Bipolar designs in amplifiers. Well as per many experiments and articles debating this issue over the web, A mosfet design is more musical than a bipolar one. Many of those articles claim, Mosfet designs perform better in mid to Hi frequencies while bipolar amplifiers are identical or more better than Mosfet for low frequencies. Well this is still a debated issue. An authentic article that discusses comparison between Mosfet and Bipolar is written by Jeff Kuells. Its an unbiased and clear cut comparison of both devices, combined with a history of amplifier designs.
An interesting discussion is going on CrazyEngineers Forums on the same topic. Have a go through both; the article by Jeff Kuells and Crazy engineers forum. Though a little time consuming, you will get a wide variety of perceptions from people across the world on this topic.
The interesting difference you will notice on both, will be about the Driver stage. A bipolar design requires a heavy driver stage (take into account there ability to drive large amounts of current to the load); where as a driver stage design for a mosfet amplifier design does not demand such a load requirement. More over bipolar designs require heat sinks (some times really large depending on the output power) which makes the whole design and amplifier device as a whole large. Mosfets are more convenient when we take this account.
If you have felt any comparable differences while designing with Mosfet and Bipolar or experienced any commendable observations,please share it with us using our comments section.