Not being an electronics guy, I’m looking for a little help.
I’m using a TIP120 darlington transistor (TO220) as a single component audio amplifier directly connected to Arduino Pro Mini for the audio input. The application is in small RC airplanes so I’m using the available 5 volts from the ESC to power the Mini and the 11 volts from the LiPo battery to power the audio circuit. Beyond that, are no voltage regulators, resistors, or capacitors involved at all. I’m using a 5watt exciter-type speaker, (where the speaker front is attached directly to the fuselage, and the fuselage acts as a sounding board for the speaker to increase volume).
Wiring is straightforward: Speaker to collector and, +11volts. TIP120 base to Arduino audio out pin, emitter to common ground, collector to speaker. This arrangement seems to work well in terms of audio quality and sound volume. Sound-on cycle time not continuous, but is only in short bursts of a few seconds, and both the TIP120 and the speaker get “warm”, but not “hot”.
Is there a better way to achieve this minimalist approach, (single component audio amp), and keep, or increase, to sound volume, using a something other than the TIP120? I’ve seen a lot of other comments about using a mosfet instead of a darlington, but is that not an appropriate application for my purposes?
Thank you all.