Just bias with a battery on one output . It works . I will order a pair of this and try out in bridged single supply . Thanks for the spice models , I wonder how you could find it .
Compensation input doesn't work neither. I couldn't find bellow 40$ a pair , too expensive for me to try it out.
Compensation input doesn't work neither. I couldn't find bellow 40$ a pair , too expensive for me to try it out.
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This is an interesting IC and looks very useful. I have not used it before but looking at the data sheet it appears that the N and P connections need to have a sense resistor to tell it how much current is flowing. As you are using this in a Circlotron mode and leaving the “P” not connected, there is no current to sense and the IC probably has one of its safety features now active to prevent damage.
Try setting it up in spice per the recommended schematic to see if it models correctly. My guess is that you need a Rq. You might be able to fool it by connecting P from each across (in an X crossover) a Rq strapped across the the gate stoppers for the N channels? But most likely, you cannot use this in a Circlotron as it is designed for consumer (single function) push pull amps.
Try setting it up in spice per the recommended schematic to see if it models correctly. My guess is that you need a Rq. You might be able to fool it by connecting P from each across (in an X crossover) a Rq strapped across the the gate stoppers for the N channels? But most likely, you cannot use this in a Circlotron as it is designed for consumer (single function) push pull amps.
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xrk971,
The resistance RQ 12k, is often absent :
LME_AMP_SCHEMATIC.pdf - Google Drive
http://forum.vegalab.ru/attachment.php?attachmentid=177568&d=1361379853
http://ddata.over-blog.com/1/74/30/05/Zipy_BB/Fab/Fabrique/Tutoriel/Zippy_BB_Tuto_V4.03.pdf page 22
an other lateral mosfet without RQ
LME49830 Project/Boards...
The resistance RQ 12k, is often absent :
LME_AMP_SCHEMATIC.pdf - Google Drive
http://forum.vegalab.ru/attachment.php?attachmentid=177568&d=1361379853
http://ddata.over-blog.com/1/74/30/05/Zipy_BB/Fab/Fabrique/Tutoriel/Zippy_BB_Tuto_V4.03.pdf page 22
an other lateral mosfet without RQ
LME49830 Project/Boards...
The Osense resistor is a output offset protection I do not see any current measurement,, it drives when offset or over voltage the mute active. Th outputs are current source loaded so it can work as a slinge output amp for as far I do not miss something.
The orgininal model has the bias simulation removed, therefore I can not simulate the setup, because it is quite a simple schematic just build on test board and try.
I do not understand why a chip manufacturer does such strange things like shut off some functions in simulation, not very good for selling.
regards
Just get a $250 Owon copy of a Tektronix. i am very happy with mine - the buttons and interface and feel all are excellent. 1Gs/s, 10k points memory, 100MHz. Color LCD, Ethernet... list goes on and on. I don't much like USB scopes because they tie up a pc and just don't "feel" right. The knobs and ability to push buttons is very important to an O-scope when debugging things. It need to be a tool that works rather than a piece of software you futz with. Yes, it is 2x more expensive than a USB scope but well worth it.
For example:
OWON SDS1102 Digital Desktop Oscilloscope 100 MHz bandwidth 1 GSa/s sample rate 10K pts wavelength: Amazon.com: Industrial & Scientific
For example:
OWON SDS1102 Digital Desktop Oscilloscope 100 MHz bandwidth 1 GSa/s sample rate 10K pts wavelength: Amazon.com: Industrial & Scientific
I wonder if the THAT1646 used the way Wayne Kirkwood re-jigged it as a Class A amp driver, can be used for a circlotron? It has a BD139 used as a sense Vbe on the input, and the differential driver output is used to drive a push-pull. I have built it and it is very clever and low,low THD.
Here is the circuit as implemented by Prasi:
My build:
FFT:
Now can we use two of these to drive circlotron?
Here is the circuit as implemented by Prasi:
My build:
FFT:
Now can we use two of these to drive circlotron?
I wonder if the THAT1646 used the way Wayne Kirkwood re-jigged it as a Class A amp driver, can be used for a circlotron? It has a BD139 used as a sense Vbe on the input, and the differential driver output is used to drive a push-pull. I have built it and it is very clever and low,low THD.
Here is the circuit as implemented by Prasi:
My build:
FFT:
Now can we use two of these to drive circlotron?
Maybe this with a compound output stage? can be made as 3 x for better drive.
Updating LTspice is not always a good idea, I have now trouble with the AD opamps. like AD823 do not sim anymore, as more schemayics now do not work anymore.
National Semiconductor produced a development board for the LME49830 -- you will occasionally find them "populated" on EBay.
I have several tubes of LM4702 -- a DIYAUDIO adherent wrote an application note illustrating how to use the '4702 with MOSFETs.
http://www.ti.com/lit/an/snaa045a/snaa045a.pdf
I've used the '4702 with both Darlingtons and Renesas MOSFETs and prefer the MOSFET sound.
With respect to the compensation pin, Troy told me that it dramatically affects slew rate -- he was going to write an application note on this aspect, but National scaled back.
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With a 604 you can not drive mosfet gate capacitances, can limit frequency.
I get some idea, go try.
regards
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