Quote:
Originally Posted by bojan
I checked the waveforms on my "fake" SJ588, and they seem OK ( http://www.ebay.com.au/itm/USB-2-0-3...item19c8d67d39).
(BTW, it is not quite what was advertised - it has only one red LED, and on ebay photo I can see two.. but it doesn't really matter).
Reference (2.5V) is at left side of the large ceramic cap placed between audio sockets, as marked on the photo (other side is GND). |
Yes, seems identical to my "fake" (a CM-109 chipset). But the output voltage swing of mine are from 0.38V to 3.91V, centered at 2.13V
You can measure the impedance of "ref" line? If is high (>100 ohms), is not suitable for my analog circuit "for SJ588", being preferrable use the "for HY544" version (and replacing "common" to "USB ground").
Maciel