I am planning a DIY electronics project with the goal of designing an amplifier that can drive speakers with high fidelity and power for my home audio system.
I am going to use either the BD246C or TIP42C transistor as the core of the amplifier to provide the amplification needed to drive the speakers to high volumes. These two transistors look similar, does anyone know which one is better?
I am going to use either the BD246C or TIP42C transistor as the core of the amplifier to provide the amplification needed to drive the speakers to high volumes. These two transistors look similar, does anyone know which one is better?
They are both bad in the second breakdown region. Stand just over 40v for 1A. That means you should not go over 2 x 25v power supply.
That gives maybe 25w in 8 ohms or 50 w in 4 ohm speaker.
If you consider the tip141 darlington they have about 60v for 1A So you can use them up to 2X35v PSU.
If you change to mosfets most of them have no second breakdown so with them you can use all the power they are made for.
IRF540 +9540 is good enough for 50w in 8 or 4 ohms and IRF140 +9540 100w.
They stand full effect for the full voltage so you can parallel them for higher power.
That gives maybe 25w in 8 ohms or 50 w in 4 ohm speaker.
If you consider the tip141 darlington they have about 60v for 1A So you can use them up to 2X35v PSU.
If you change to mosfets most of them have no second breakdown so with them you can use all the power they are made for.
IRF540 +9540 is good enough for 50w in 8 or 4 ohms and IRF140 +9540 100w.
They stand full effect for the full voltage so you can parallel them for higher power.
I am using 2SD2390/2SB1560's in my home amp, they are darlingstons with an embedded 70 ohm base stop resistor. I have seen them used in Pioneer and a Denon AVR. Really good performance characteristics.
Here's one you can build with cheap, easy to find components. 2N5551/2N5401, BD139/140 and IRFP(9)240. That's it. Running tests on it right now. It's still a little bit work on progress, but I've spent the entire day testing it and it performs really well!
50W, >0.008% THD, 20Hz - 900kHz, >20V/us slew rate. Should be perfect for a mid-range home audio system,
https://github.com/prydin/the-bog-standard
50W, >0.008% THD, 20Hz - 900kHz, >20V/us slew rate. Should be perfect for a mid-range home audio system,
https://github.com/prydin/the-bog-standard
Neither = slow weak general purpose pointless transistors
Go to power transistors are usually
NJW1302G
NJW3281G
Something cheaper same old
2SC5200
2SA1943
And likely many different suffix they are listed under
with different packages and power ratings
FJL4315
FJL4215
2SC5242
2SA1962
FJA4314
FJA4213
etc etc etc
NJW1302 stands for 1A and 85v or 100v and has 400 to 600 pF Cob
SJ5200 stands for 0,4A att 100v and has 200pF Cob
SJ5200 stands for 0,4A att 100v and has 200pF Cob