1. No, it's a line level output right off the DAC'Gruso' said:1. Will the stereo audio level be controlled by the volume wheel?
2. Is a 5V supply available at the EXT port?
ashaw:'MWeston' said:2. No, it's a 2.8V supply at up to 200mA
I think not. I was referring that you seemed to suggest 2.8v for the TXB0104's A side but the line level is 1.8v.'MWeston' said:You've misunderstood the purpose of the TXB0104. It separates the two systems so that each one can connect together without burning out the other one or being too "low" to be read.
Thanks for the breakout board schematics (i had looked for them but didnt find).'MWeston' said:Here's the schematic for the breakout board: http://openpandora.ca/schematic/AV_Board_schematic.pdf
I was going to run an AVR (ATMega88) on the CTS/RTS lacking (AVR doesn't have them natively either) serial port to create a parallel port (needs 5V power) using a high serial speed of 1.8432 Mbps (which needs 14.7456Mhz for the atmel - which is above 10Mhz - which needs 4.5V-5.5V) (the OMAP3 can (from the OMAP35x tech manual) reach high serial speeds (max 3686400)) . I was also going to just add a normal ST232ACN (5V chip) serial level converter and a DE-9 (std serial) connector to the another (w flow control) serial port.'ashaw' said:Do you really need 5V because if you could use 3.3V i have a cuircuit for a boost buck all ready done up.
I don't see a big need for the files now (for me), but ofcourse i could take a look at them... Anyways i have a few points to make here:'ashaw' said:thankyou, would you like the files for my optimised voltage convertor, I am thinking about making a little board that contains a DC-DC boost convertor and a TXB0108 switchable between 3.3V and 5V the board is currently 21mm by 23mm, I think I can get this board to 2cm by 1cm if I put components on boath side of the board mabe even smaller, I will put a XMEGA A1 on this board too if it fits well.
Oh My God... That looks both a) Great! and B) truly not assemblable by me...'ashaw' said:I have finished my board, Though i fear that the assembaly is not for us mere mortals it does have the proparty that it can be soldered into a dip header socket such as this one Mill Max 150-40-316-00-001000
Please find a pdf containing layout and a schematic at
http://www.alexisshaw.com/voltageconvertor.pdf
please give me some feedback as i intend to have a few of these made up and then to pot them, they are switchable by a rotary switch on the top, and have a built in boost convertorfor 3.3/5 V
PM me for gerbers and Drill files.
I did take a second (longer) look at the pdf. Since you routed the 1.8V line out, it could be changed to handle boost&I/O from "any" single voltage by just desoldering (relatively simple thing i think when you know what you're doing...) the 1.8V regulator and then putting the single voltage to both UB and "1.8V" lines.'ashaw' said:it looks like the price for these is about 20 US at qtys of 100 pcs getting a quote for the boars now. the 1.8 V converter can easily be replaced for the equivelant 3.3V part with only a chane in 1 part.
I can see why...'ashaw' said:I will probably send it to an assembly house to have made up. this is not to be made up by mere mortals.
Truly WTF/Hard to believe. That PCB is fully SMD with 4 layers (if i read the pdf correctly - took a while to figure out why i couldn't "get it" (was trying to interpret as 2-layered)). Compare to: My first PCB was a single layered through-hole thing with very wide traces. It propably had a few 74-series chips and propably did something stupid (i don't really remember - it was a school work).'ashaw' said:I need to have this looked on by someone that knows more about PCB design as this is my 1st PCB.