Question Regarding Old TDA LA4440

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I have about 10 LA 4440 IC lying here , so i am thinking to build a bi-amped system , all running in bridge mode . But my problem is that data sheet has
> two schematic , one has voltage game of 51.5 and another has 57 .
> Second is that does this IC provides 19watts rms ? or peak ! :confused:
> third it does not provide anything about it's sensitivity ? How will I know at what input voltage it provides 19watt max output ?
here is link to .. look at it and tell me what to do !!
LA4440 Datasheet pdf - 6W 2-Channel, Bridge 19W typ Power Amplifier - SANYO
 
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Gain is set by Rnf. Datatsheet has a chart showing gain for different values of Rnf.

19 watts is peak value with 10% THD. you can probably get 10 to 12 watts into a 4 ohm load below 1% distortion, but it's a very bad sounding chip.

Sensitivity is also clearly shown in the datasheet, with output power as a function of input voltage for all three sample schematics.

Good Luck.
 
Gain is set by Rnf. Datatsheet has a chart showing gain for different values of Rnf.

19 watts is peak value with 10% THD. you can probably get 10 to 12 watts into a 4 ohm load below 1% distortion, but it's a very bad sounding chip.

Sensitivity is also clearly shown in the datasheet, with output power as a function of input voltage for all three sample schematics.

Good Luck.
Well Sangram bro , I know that this is not the best IC but yet . I can power 20Watt RMS Speaker well enough and it sound good , i should say this sound better than those tiny Creative speaker . And has much better sensitivity , the only problem is distortion . Like all tda ic , which all distort about 10% at full . I will run these speaker at 10watt rms , those data sheet are not clear , by any mean , worst kind of sheet .
Any by the way why will sound be clipped ? I am not over driving speaker . :eek: . Everything should sound perfect . Still two problem is not answered , exact voltage and it's output . is it a rms or peak
 
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I don't remember saying anything about clipping. It's low bandwidth and extremely high IMD makes it unusable for any application with reasonable quality. It's a low cost car radio chip from the 1990s, and that's pretty much all Sanyo ever designed it for, with high ambient noise you don't notice much quality anyway in the cars back in the day.

The datasheet has everything you need. The power outputs are RMS and not peak. For input sensitivity (I assume this is what you mean by voltage), you have to calculate the output voltage (P=V^@/R) and divide by the v/V gain figure to find out how much input voltage is needed. At ~56dB, it is around 6.5mV, but for the three schematics, there is a graph provided by the manufacturer, plotting output power against input voltage. If you do not use the schematics, manufacturer has also provided a graph of dB gain vs RnF value. I don't understand which of your questions are not answered by the datasheet. It was made 20 years ago on a typesetting machine and then scanned as an image so it will not have the quality of the newer sheets, but neither does the chip :) If your benchmark is a small Creative PC speaker, then yes it is possible that it will sound better than that though. But as a few other Indian DIYers here will tell you, to get reasonable sound you have to look past the offerings in the local market. No offense meant.

Good luck with your project!
 
I don't remember saying anything about clipping. It's low bandwidth and extremely high IMD makes it unusable for any application with reasonable quality. It's a low cost car radio chip from the 1990s, and that's pretty much all Sanyo ever designed it for, with high ambient noise you don't notice much quality anyway in the cars back in the day.

The datasheet has everything you need. The power outputs are RMS and not peak. For input sensitivity (I assume this is what you mean by voltage), you have to calculate the output voltage (P=V^@/R) and divide by the v/V gain figure to find out how much input voltage is needed. At ~56dB, it is around 6.5mV, but for the three schematics, there is a graph provided by the manufacturer, plotting output power against input voltage. If you do not use the schematics, manufacturer has also provided a graph of dB gain vs RnF value. I don't understand which of your questions are not answered by the datasheet. It was made 20 years ago on a typesetting machine and then scanned as an image so it will not have the quality of the newer sheets, but neither does the chip :) If your benchmark is a small Creative PC speaker, then yes it is possible that it will sound better than that though. But as a few other Indian DIYers here will tell you, to get reasonable sound you have to look past the offerings in the local market. No offense meant.

Good luck with your project!

Thanks for reply bro , well frankly speaking I did not know formula to calculate , gain and sensitivity > Yes "How much input voltage is required to output full 19watts" and thanks for your answer your gave me what I need . And no offense taken . But bro you know People still love valve amps , they still too old , old is not always bad . Well I am not talking about Creative Mini 500Rs Speaker . I was talking about 2.1 Inspire . They Uses TDA8510J > Which also Has 10% THD @ Full Load . Only thing special about this driver is that it's 3 way output . Anyway thanks for your help again
 
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