Problem with linear regulation is that it's harder to sink all the regulator heat away with mediocre heatsinks. isnt as easy as it seems.

SMPS however, has much higher efficiency so heat is not so much of an issue.

No dice, sigma by default is only good up to 6 Watts.

You need something that exceeds the maximum output of the T-amp by some margin.

THD = Total Harmonic Distortion
-THD is a form of distortion measurement by comparing the input frequencies and the output frequencies by using FFT (fast fourier transform, time domain to frequency domain so you can observe amplitude vs frequency)

Impedance = Is a general term to coin all sorts of "resistance". There are "reactance" (formed by inductance and capacitors, frequency dependent) and "resistance" (formed by resistors, not frequency dependent).




You cant "increase" the current.

Current is drawn based on the demand of the load. Basically, it is limited by device (heat and threshold before the silicone breaks down) and your output impedance. The Sigma might use a MOSFET with 8A capabilities, but with the stock heatsink, it's not going to work well enough.

I'm not stopping you from trying, but you should do the calculations before proceeding. The weather here is very unlike the US so you might want to give it a few +/-


You can calculate the effective wattage of Sigma11 approximately with Vi (input voltage) - Vo (output voltage) multiply with load current (just get the max current the T-amp pulls under max load). Again, in short, the more voltage you drop across your regulator, the lower the maximum wattage the regulator can supply.

stranded is somewhat better than solid core in technical aspects.

For instance, skin effect, where the frequencies only travel on the surface of the conductor. Stranded somewhat increases the surface area of conduction.

I use solid core all the time for internal wiring for electronics. Much better and cleaner work. It's really just your preference.

Do not however, use solid cores for high power cables or long external cables because they don't bend flexibly.


Protip: Mechanical considerations.

sijosae's hybrid desu

get the compact tube hybrid.

To get the absolute specs, you need to refer to the datasheets of the ADC stage of the sound card.

the resistor setup is to current limit and provide okay-ish input impedance for the load. I think all is well if you prevent too much current leaking towards the input of the Soundcard. Need to do your maths here.

Basically an ideal OSK when measuring voltage has very very high impedance (so that input current becomes moot).

I don't know what you're fixing but, something that samples at 44.1KHz isnt going to capture oscillations occuring at 1MHz and above.


EDIT: I see you're also into arduino. Any reasons for going with the Arduino route? I'm trying to design a high end attenuator + IR RX/TX control + LCD system for amplifiers but I don't know what chip to use.

My only experience is C Language + 8051 based microcontrollers, so I think I'm fine with anything that works with C.

This post has been edited by LittleGhost: Oct 23 2010, 03:05 PM

Nyquist theorem states that you can only construct an original undistorted signal at a maximum of half the sampling frequency, so for 44.1KHz, you can only get 0-22KHz at most.

315MHz is VERY VERY high, it is not possible to be measured by means of normal oscilloscope. Even my Tektronik only goes up to 60MHz.

not enough info, what are you building?

both are the same PDIP (8 pin IC) package. Get the cheaper one.

Most likely different batches.


Btw do take note that these are PDIPs, not the usual TO-92 most designers choose to use. You can modify it very easily by clipping off the unnecessary pins and bend the other three pins you want straight to simulate a TO-92.


All PDIP TLE2426 have noise reduction pin. It's probably used as a rail to ground filtration. If you're already having caps rail to ground after the TLE2426, you won't really need to use this.

This post has been edited by LittleGhost: Dec 3 2010, 01:56 PM

PGA2310

Maybe it's the inferior DS1802. You can interface your PIC ADC to track an analog pot (can be mono), and then interface it to the DS1802. Problem is that it does not perform as well as other options. Thing with the DS1802, it's also very easy to use without a PIC if you only use push buttons.

Honestly since you know how to use a PIC, go with better chips. In fact, just like what I did in the past while being amazed by the PICO amp with the digital pot, head over the big sites and run through their catalog. You'll be surprised by how many different chips that can cater to your needs if you're well versed in using the PIC.



For people like me who prefer big ass amps, small chip digital pots are not favorable when you can use a set of relays with matched resistors instead. This is of course a superior option however it takes up a lot of space. Also, most if not all digital pots are simply opamps with variable gain. I don't like my signal to go through a lowly OPA2132

SPI no problem for modern PICs

the ma huan is the most enjoyable part of the process

SPI transmission. Not very hard lar. Just read up the notes and you should be fine. The last time while I was doing 8051 I had to simulate an internal SPI using software emulation. With modern PICs, the SPI clocks are easily generated. Should be okay wan...

Just like the PS2 controllers, semua guna SPI protocol.

PS2 as in Playstation 2 controller lol.

What PIC are you using? ATMEGAs? They have a list of documents on applications.

For your use, you just need to find the articles listed together with the PIC (if you're using atmel)

Just use master to slave mode to control your chip.

EDIT:

To make it easier for you to follow, just do this:

1) Generate SPI Clock first. Fast is good but depending on the chip you're trying to communicate you might need to adjust this a little bit.
2) Next, the function C should include SPI send byte, and SPI interrupt that checks whether the transmission went well.
3) When you have these functions working, you should be able to send whatever digital streams you need to your PGA2310

This post has been edited by LittleGhost: Dec 8 2010, 10:37 PM

I posted something else, look above.

EDIT: Shitttt, this thing is poisonous. I have a big urge to build one also. I have alot of papers next week. how does i refrain? LOLLOL.

This post has been edited by LittleGhost: Dec 8 2010, 10:42 PM

just pm me for it after this week.

I have too many shit to do this week (4 tests and 1 lab :|)

Yes you will because the TLE2426 will fight with each other.

Just buffer the ground channel with a beefy opamp.

Head over to tangent's site tangentsoft.net on his article about virtual grounding. It's somewhat incorrect in small parts but is still a very good read.

f***, it's christmas and I'm slaving my ass for this boring Advance uP subject.