Yes, these are resistive load measurements. I stated that one must consider reactive speaker loads when I originally posted those charts.
At 24v 4ohm load, the peak current is 2.2 amps. The data sheet shows the peak current to be 3 amps at 0 volts across the output transistors, rising to over 4 amps from 5 to 20v. This is a safe margin for MOST reactive loudspeaker loads. I'm NOT saying it is safe for all conditions. You seem to want a pass or fail condition under the most stringent of conditions which is fine, but I'm saying the OP is likely to be just fine bridged with 8ohm load at 24v supply. He should build the amp, measure the output current with his speaker loads. Nine times out of ten he will be just fine.
still i don't get why would anyone bother bridging 2 lm1875 ic, when 24vdc is available, instead of using sta540 witch is just perfect with single 24 vdc supply, and has no problem with an 8 ohm speaker in bridged mode.
its space efficient, supply voltage is ideal, the load is within what it can drive, has less components, it seems to be the ideal choice .
its space efficient, supply voltage is ideal, the load is within what it can drive, has less components, it seems to be the ideal choice .
glad i was able to help.
usually i kindof better like to find a suitable chip for the job, rather than to force-employ one for a job.
surely its less genuine thisway, but heck. given this instance one can simply build the sta even without any pcb at all, and will preform quite well. i have built a few amps with this ic for a variety of tasks, and i'm quite pleased with it. it is quite rugged, and brutally simple.
usually i kindof better like to find a suitable chip for the job, rather than to force-employ one for a job.
surely its less genuine thisway, but heck. given this instance one can simply build the sta even without any pcb at all, and will preform quite well. i have built a few amps with this ic for a variety of tasks, and i'm quite pleased with it. it is quite rugged, and brutally simple.
LM1875 works off of a higher voltage than STA540. Other than that, it is limited in every way for a bridge amp.
It seems like the real worthwhile bridge amp would be a bridged 3886. I think you could get 100 watts into 8 ohms easily without pushing the limits of the chips.
You keep pushing that STA540 Artie, and after looking at the datasheets a few weeks ago, it seems quite compelling. It only needs a couple of parts to work and you could make the board extremely small. I must check it out after I get a couple more projects done.
It seems like the real worthwhile bridge amp would be a bridged 3886. I think you could get 100 watts into 8 ohms easily without pushing the limits of the chips.
You keep pushing that STA540 Artie, and after looking at the datasheets a few weeks ago, it seems quite compelling. It only needs a couple of parts to work and you could make the board extremely small. I must check it out after I get a couple more projects done.
an interesting application of sta540 is connecting it up as a bridge/paralell amp.
i done one with no ballast resisotrs or what so ever, and despite the crude implementation, its still working in a truck. the amplifiers inside the chip are verry well matched. TDA chips simular to the STA allways gave the ghost up in a ballastless bridge/paralell config.
i done one with no ballast resisotrs or what so ever, and despite the crude implementation, its still working in a truck. the amplifiers inside the chip are verry well matched. TDA chips simular to the STA allways gave the ghost up in a ballastless bridge/paralell config.
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