what are the formats that are used? how to distinguish between them? can sometimes two different names or designations mean the same thing?
I want to change the cs8412 and df1700 in my dac in favor of a wm8804 input receiver and df1704 digital filter, I found a few modules that use those two chips and claim to be able to replace the cs8412 and df1700.
after diving into the data sheets of the df1704, I noticed that it has no "MSB first two's complement" input like the df1700 it is supposed to replace, but it does say that is has sony standard, is it possible that the sony standard is the same as "MSB first two's complement"?
I want to change the cs8412 and df1700 in my dac in favor of a wm8804 input receiver and df1704 digital filter, I found a few modules that use those two chips and claim to be able to replace the cs8412 and df1700.
after diving into the data sheets of the df1704, I noticed that it has no "MSB first two's complement" input like the df1700 it is supposed to replace, but it does say that is has sony standard, is it possible that the sony standard is the same as "MSB first two's complement"?
I2S is a format, "MSB FIRST" is a description of one aspect of a format. The timing diagrams in the DF1704 datasheet show the three formats clearly - Sony (which is a right justified, MSB first), Left justified (a left-justified MSB first format), and I2S which is one-bit offset from left justified. They all clock on bit clk (BCLK) falling edge and have a left-right clock, LRCLK. So all of its modes are MSB first two's complement in fact.... See the top of page 8 of the datasheet.
If you look in the pin functions you'll see pins 3,4,5 control which format is used at what bit-depth.
If you look in the pin functions you'll see pins 3,4,5 control which format is used at what bit-depth.
And:
Is the next aspect of a format.
However, in PCM it is always "two's complement".
Alex.
thank you! so as long as it is PCM it is two's complement, that's good to know!
also, I am going with the cs8414 instead of a wm8804, the wm8804 can't drive the df1704 with its output voltage.
also, I am going with the cs8414 instead of a wm8804, the wm8804 can't drive the df1704 with its output voltage.
Why?
DF1704: VinLmax=0.8, VinHmin=2.0v
WM8804 @DVDD=3.3v have VoutLmax=0.33v, VoutHmin=2.97v.
0.33<0.8, 2.97>2.0, so this is not an issue.
Alex.
I was referring to the digital characteristics:
df1700 needs 4.75v to 5.25v and wm8804 outputs 2.7v to 3.6v.
df1700 needs 4.75v to 5.25v and wm8804 outputs 2.7v to 3.6v.
Vcc is not important, important are "0" and "1" voltages for input and output.
For "0" - max output voltage must be <= than maximum input voltage.
For "1" - min output voltage must be >= than min input voltage
and max output voltage must be <= than maximum input voltage.
All these conditions are OK in case of DF1700 and WM8804 direct connection of - see values in the previous message.
Alex.
For "0" - max output voltage must be <= than maximum input voltage.
For "1" - min output voltage must be >= than min input voltage
and max output voltage must be <= than maximum input voltage.
All these conditions are OK in case of DF1700 and WM8804 direct connection of - see values in the previous message.
Alex.