LME49830 Reference Design Amplifier

[jackinnj]

Too bad the chip has been discontinued. This is a first go FFT of the LME49830 driving 2SK1530/2SJ201. The output devices are closely matched, bias current set to 250mA. I was fortunate to get the original NatSemi EVM boards several years back.

 

[adason]

Has SONY been using this chip in some of their integrated amps?

 

[jackinnj]

@adason -- dunno

The above FFT is 10W/8 Ohms per the EVM manual. There is a difference from the charts in the manual in that 2nd seems dominant. I think the THD+N is 0.002%, a bit higher than the EVM manual -- but that's like counting angels on the head of a pin.

 

[ostripper]

Has SONY been using this chip in some of their integrated amps?

No , but similar TDAxxxx's. LME/TDA = Most of the amp , except the output stage. Symmetrical amps with extra thermal ,mute , auxiliary circuitry.
I think even the pre-drivers are in the IC , you end up with an EF3 , if you go BJT. can also drive FET's directly.
OS

 

[adason]

My bad, i have plenty of other chips from sony integrated amps...uPC1188H. Not that impressive.

 

[tomchr]

Yeah. The LME49810/811/830 were pretty awesome chips.

Tom

 

[jackinnj]

Here is one of the channels waiting to be fitted into the Sumo Polaris "carcase"

 

[jacques antoine]

Hi Jackinnj:
I still have some 498xx around. Any schematics/pcb drawing you would like to share?

 

[pieter t]

https://www.diyaudio.com/community/...-on-the-lme49830-with-lateral-mosfets.196932/

 

[jackinnj]

Hi Jackinnj:
I still have some 498xx around. Any schematics/pcb drawing you would like to share?

The design uses the Nat Semi EVM => evaluation module and the "Reference Design" with K1530 and J201 MOSFETs. It's still available as a PDF on the TI website. One board uses the single pole comp, the other uses the dual pole comp.

These EVM's come up for sale occasionally. I think you can make a more compact PCB by simplifying and eliminating a number of the test points on the EVM

The unloaded rails from the Polaris Sumo will deliver +/- 56VDC so with a pair of P and N MOSFETs this should be a very robust amplifier.

I am going to put the original Polaris Sumo PCB's up for sale on Ebay.

 

[jackinnj]

I would like to hear the experience of others using the two pole compensation scheme.

 

[jackinnj]

My last LME49830 is installed and working with the Toshiba MOSFETs.

 

[amplidude]

Interesting, the other day I found 10 lme49810/lme49811 bought ages ago, could he fun putting them to use

 

[jacques antoine]

Interesting, the other day I found 10 lme49810/lme49811 bought ages ago, could he fun putting them to use

I'm interested too!

 

[jackinnj]

Just to note, this series of chips in the Reference Design use the Aavid HS335 heat sink. This has a little clip which holds the chip to the sink. Thermal resistance is 6.3 C/W. I have a few of these left over, but they are also available from the usual suspects.

The easy way to determine PdMax for the thermal resistance is to multiply the absolute supply rail voltages, Vcc + |Vee|, by the quiescent current (which is constant).

 

[jacques antoine]

My last LME49830 is installed and working with the Toshiba MOSFETs.

Vertical mosfets I presume? Not sure Toshiba manufactures latfets?

 

[jackinnj]

j201/k1530 but i have Hitachi's as well. the evaluation module is designed for Toshiba's, or IRF-Vishay pinout (GDS).

 

[pieter t]

Should work well with Hitachi/Renesas 2SK1058/2SJ162 I guess?

 

[jackinnj]

You can do both. The Hitachi/Renesas do not require a temperature sensing transistor.

Heck, could also do some boards for the OnSemi Thermal Trak.

I have one amplifier which I rarely use anymore -- based upon the LM4702 (which begat the LME49810,11 and 30). I still have the PCB in Ultiboard. The Nat Semi boards give a few more ideas.

 

[jacques antoine]

I have a bunch of old Sanken SAP16N/P thermaltrack darlingtons. I wonder if I can use those with the LME49811.