y1 gamma-1 DAC - Page 90

I'm trying to make a complete order for an y1 and possibly an y2 at mouser by using the BOM. Well, all parts expect the ones you can order from amb.

Most parts are in stock, though three parts are not and I could need some help ordering replacements if possible. These are the ones not in stock:

R7U; 270-560-RC

R9U; 270-110-RC

U4U; 595-SN74HCU04D replaced by 863-74HCU04DR2G

Regarding both resistors R7U and R9U, does the size and voltage matter regarding a possible replacement as all similar ones are and bigger and higher voltage.

Regarding U4U, reading through this topic and others, the above mentioned replacement should be ok right?

You do not need this or the LED but if you wish to install them you can sub with # 270-562-RC

You can sub with # 270-113-RC

Yes.

For R7U you can substitute with 270-562-RC, for R9U substitute with 71-RN50C-F-110.

Your U4U choice is fine.

EDIT: MisterX beat me to the punch. ;)

@MisterX and amb, many thanks!

Any help with my post on the previous page?

What are the numbers on the IC you have installed in the U2U position?
 

Quote:

Originally Posted by Ntropic 

Any help with my post on the previous page?

A08G, as specified.

Ntropic, make sure U1U is soldered in the correct orientation (the dot on the chip should match the dot on the board).  Also check your soldering of U1U's USB input pins, and of the USB connector itself.

The chip is in the correct orientation. I'll reflow U1U and the USB connector to be sure though.

I got a, hopefully, simple to answer question regarding U1U.

As can be seen below, somehow the copper traces of pin 7 and 8 came loose when soldering. (I take full responsibility for that!) I managed to get the trace on pin 7 to get back to it's original position, though the trace of pin 8 went missing. As the PCM2707 is used for USB interface and conversion to either S/PDIF or I²S, does it mind to keep things as they are at this moment? As according to the datasheet, pin 7 and 8 are used for volume up and down respectfully.

If not, is there any way to clean this one up? 

It's OK, those pins are not used in the Y1.

Quote:

Originally Posted by MisterX 

It's OK, those pins are not used in the Y1.

Just as I thought, thanks for for clearing it up!

so when i plug my USB in (im almost positive that everything else is a clean solder) i get usb device not recognized, and when set to USB mode the U1U chip gets rediculously hot, what does this mean? does this mean the U1U chip is dead or is it somewhere else?

i re-flowed the joints and inspected with magnifying glass and there are no bridges. also if it is any conselation both the 3.3V and 4.5V test points read 2.73, JP2D pin 3 reads 4.72, the wires underneath the board are all solder correctly and with good joints.

can you help me?

EDIT:just tested for 3.3 and 4.5 test points i was getting 2.95

Are you sure you have U1U installed the right way around?

Quote:

Originally Posted by MisterX 

Are you sure you have U1U installed the right way around?

aaaaaannnnnnndddd cue feeling like a idiot

ugh this is about to BE SO MUCH WORK, do you have any smd desoldering tips?

also would this clear up the voltage issues or would that be on like U2U/U3U?

EDIt: nvm pads came off when i tried to desolder it, i cried a little on the inside, looks like ill be getting a new board

is it possible to rejoin the 2 boards? like the DAC board is in fine shape, or maybe ill just omit the USB feature, i was planning on using a toslink anyway, plus im building a sigma-25