8r vs 4r power
I have been searching through the data sheets and this thread to try and understand the 4r vs 8r output power relationship for the tpa3116d2 implementation. The rating is 50wpc into 4R but would this not halve to 25wpc into 8r which would make it less than the 3118 implementation?
Or will the 3118 only manage a maximum of 30w into both 4r or 8r due to current limitations and effect on chip temperature whereas the external heat sink will allow the 3116 to achieve the higher total power rating.
Many thanks in advance!
I have been searching through the data sheets and this thread to try and understand the 4r vs 8r output power relationship for the tpa3116d2 implementation. The rating is 50wpc into 4R but would this not halve to 25wpc into 8r which would make it less than the 3118 implementation?
Or will the 3118 only manage a maximum of 30w into both 4r or 8r due to current limitations and effect on chip temperature whereas the external heat sink will allow the 3116 to achieve the higher total power rating.
Many thanks in advance!
If AliExpress has already denied the claim, it sounds like the only thing left to do is see if you can dispute the transaction with your credit card issuer.
I saw a YouTube review of this board -- the guy had bought two other 2.1 boards that were both turds, but he said this one was good. I've also bought two that were defective (including one of the ones the YouTube guy bought).
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Because the loading of 8R is less than 4R, the amplifier is able to drive the 8R with more voltage swing,
Therefore slightly more than half of the output power rating at the same distortion level.
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i need some advice:
i ordered this amp here: Aiyima Assembled HIFI digital power amplifier TPA3116D2 2.1 high power board 12 24V subwoofer bass board-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
but it arrived damaged:
I msged the seller, but he doesn't want to resend. I made a dispute on alie, but the denied it based on the photos
i checked the resitance of the potentiometer, on the solder points and it goes from around 15kohm to 42 kohm on the outside legs. So it seems to be working.
But when i play music i am not able to adjust the bass frequency
So, what can i do? How can i send prove to alie
Desolder and straighten it up, that is what I do, but be very careful, as the solder pads on these cheap boards evaporate very easily. Just run a lead from the pot leg to where the trace ends up if that happens.
Noted with thanks Dug!
Is there a rating of input sensitivity for these? I couldn't find it in the datasheet but I may be looking for the wrong thing.
http://www.ti.com/lit/ds/slos708/slos708.pdf
Well, to me the voltage swing is pretty much the same.
at 26V the voltage swing is about 26V*0.707 = 18.4Vrms
Rds_on in the output fets is 120mR (ideally at 500mA and 21V) x2 (high/low-side).
So Pout is for 8R:
18.4Vrms*18.4Vrms/(8R+2x0.12R) = 338.5Vrms/8.24R = 41W
Power dissipated at output fets: 2.9%(*) -> 1.2W
Pout at speaker: 41W - 2.9% = 39.8W
(*): 0.24R*41W/8.24R
4R:
18.4Vrms*18.4Vrms/(4R+2x0.12R) = 338.5Vrms/4.24R = 79.8W
Power dissipated at output fets: 5.7% -> 4.55W
Pout at speaker: 79.8W - 5.7% = 75.25W
That pretty much corresponds with the datasheet specs. (But of course) The missing 5W in the 4R plot at 26V is from the increased Rds_on due to internal power dissipation.
The limiting factor with the TPA3118 is the thermal path. Both chips can put out the same power, but due to much better thermal path with the TPA3116, the continous output power capability is much higher. (More output for a longer time, just restricted from the heatsink + cooling)
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These amps are notortious for having a sub woofer crossover frequency that does nothing other than attenuate the bass. It's not frequency shifting the crossover point if that's what you were hoping it would do. I had a Breezeaudio board a few years back and measured the frequency response at various knob positions. All it does is attenuate the sub output which goes out clear to 300Hz or so. So there may not actually be anything wrong with the board. The photo is clear evidence of a damaged board. Aliexpress dispute resolution should find in your favor. However, if they want you to send back to China forget about it. It will cost $25 to do so maybe more. It's asymmetric shipping so we can't send back. Sometimes seller will send you a new one and you keep bad one so that they preserve their good ratings.
+1. The sub pot on most of these boards is volume only.
The fixed sub XO is typically a Sallen-Key topology 2nd order LP filter - Fairly easy to reverse engineer. And the equations for the filter's Fc and Q are readily available. That makes it easy to customize the boards' XOs for a particular speaker set-up by selecting new values for the two capacitors in the filter circuit.
Hey all. This would be my first post on these forums and all I gotta say is WOW. What a wealth of knowledge! Anyway I am doing a bluetooth Boombox project. First thing i got for the project is a set of JBL control one speakers and I was going to tear these apart to use the speakers out of them but I am not totally sure yet. ANyway they measure 3.2 ohms each. And I bought a amp from amazon that I thought would be great for the project. It boast 2x50 watts and 1x100 watts for a sub channel. It says it has 2 TPA3116D2 chips for the amps and a bluetooth 4.0 reciver. When I got it it was in one of those big brown envelopes and inside it was in a static-free bag and all of the pokies were sticking out the bottom of the bag and it was torn in a few spots. I didn't think much of it. I had a 12 volt 5 amp power brick for driving leds on my 3D printer so I used that in hooked up the JBLs and paired the bluetooth with my phone and let it rip. Well that's what I thought it would do?? The led does come on and it does function. It does have some noise and I suspect it coming from the power brick. I was thinking that this thing would blow me away! Not by any means . I was thinking that maybe that it was bottlenecked by the power supply. So I have a DR meter 30 volt 5 amp power supply that I hooked it up to and ran it at 24 volts 3 amps. The amp draw never went over .20 . So I am wondering if there is any other checks I can do to nail down whats wrong? I do have a Fluke 115 and a Rigol DS1054z but I am not completely competent on scope useage. I am somewhat of a noob yet. I can hit the auto button really good! LOL. I am thinking that this is going to make it's way back to amazon and a proper board will be either will be made or purchased. If you have recommendation that would be greatly appreciated. Thanks!
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Has anybody seen these boards yet, with a integrated step-up converter onboard?
DC 12V 24V TPA3116D2 BTL 150W XBS Bass Car Digital Audio Power Amplifier Board | eBay
Looks really interesting, 12v input gets stepped up to 24v. Anybody have any experience with these boards?
cheers
DC 12V 24V TPA3116D2 BTL 150W XBS Bass Car Digital Audio Power Amplifier Board | eBay
Looks really interesting, 12v input gets stepped up to 24v. Anybody have any experience with these boards?
cheers
I think you've misread/misunderstood the listing; the power input is recommended to be between 12v and 24v. There is no step-up...
At 24 V, the TPA3116 in PTBL mode will put out 150 W rms into a 2 ohm load at 1.0% THD (direct from the ti datasheet graphs). Officially that exceeds the 100 W thermal limitation of the chip.
However, the thermal limitation is based on a continuous sine wave. Music is never as dense - maybe 1/2 to 1/3 as dense as a sine wave. And the dynamic peaks that would reach 150 W are short lived. The chip / heat sink combination has thermal inertia that can dissipate the peaks before the thermal threshold is reached. And the chip has thermal protection-auto reset for over temperature.
So if you have a 24 V PS and two 4 Ohm subs in parallel, I think the chip can handle it.
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Data sheet says it can. (at > 1%thd, 26V and 2R load)
At aprox 88% efficiency That leaves aprox 20.5W of heat.
Junction to case is 1.2 deg C / W
Thermal trip point is 150 C
I guess it depends on the heat sink.
However.
They recommend 12V / 10A or 24V / 5A This is only 120 W input power.
They recommend 4 or 8 ohm speakers So probably not 150W
So at most this amp will do what the data sheet shows.
Can't do more...no magic was mentioned.
There are lots of these amps out there. If you want to know what the board might be capable of then look up the data sheet for the IC used.
At aprox 88% efficiency That leaves aprox 20.5W of heat.
Junction to case is 1.2 deg C / W
Thermal trip point is 150 C
I guess it depends on the heat sink.
However.
They recommend 12V / 10A or 24V / 5A This is only 120 W input power.
They recommend 4 or 8 ohm speakers So probably not 150W
So at most this amp will do what the data sheet shows.
Can't do more...no magic was mentioned.
There are lots of these amps out there. If you want to know what the board might be capable of then look up the data sheet for the IC used.
