DIY DAC in UK - success! sm5841, pcm69a

[PhilW]

I joined this forum in order to get help building a DIY DAC in the UK. (Getting required parts is not so easy)

I obtained CS8412, PCM69A (RS Components) and SM5841AP (Farnell UK).

I had got the CS8412 + PCM 69A working in x1 oversampling mode, but could not get the SM5841 to interface between them - hence my problem.

But today, I got it all working!. (I needed to re-set the CS8412 from 18bit mode, to 16 bit mode)

So this message has changed from a potential cry for help to a sharing of joy.

If anyone would like more details I would be happy to oblige

 

[hatasa]

Hi:

I also intrest to use the Sony transport direct into the SM5841, And the DAC would be PCM1702PK!

What mode should I set to SM5841? Thanks!

 

[PhilW]

sm5841

I discovered that there are different versions of the Sm5841 (the pdf files are on the nippon precision circuits web site).

In UK I could only obtain the 5841AP version. To adjust the settings on this requires clocking in a serial byte of control bits - I was unable to implement this within my project. So I had to use the default settings which exist when the chip resets (these are: stereo, 44.1KHz, demp= off, mute=off, input = normal [i.e. NOT I2s], ... oversampling = x8, o/p=18bit, noise shaper= on).

If you can obtain the 5841H version much of this can be set by external jumpers - this is easier to implement.

Which version are you thinking of? Do you know what kind of o/p comes from the transport?

 

[PhilW]

I've had a brief look at the PCM1702 data sheet.
The pplication example at the end shows the DF1700. The settings indicate: 20-bit o/p (which matches the pcm1702) and system clock = 384fs (see DF1700 datasheet page3.199).

The system clock i/p on the sm5841 is controlled by pin 1 CKSL,
but 20 bit o/p is not the default condition. You would definitely need either to configure SM5841H via jumpers, or clock in control pulses to SM5841AP.

Maybe others can help on this as well: I am not entirely clear where 384fs comes into it.

 

[hatasa]

I also just can get the 5841AP only!
Actrally I also have the DF1704, but conduse how to set the setting for the Sony transport!

Please advice!