Hi Sir:
We use UCD9222+UCD7242 for our C6678 CVDD power supply.
But UCD7242 can not be soldered correctly on our board. That means,
everytime when we soldered ucd7242, we tested the CVDD voltage output, and CVDD
was shorted to GND.
Can you help me to explain why?
And could you please give me the Temperature curve for soldering of UCD7242?
Thank you very much.
The UCD7242 has a rather complex set of pins in the bottom. Did you check that the pins were correctly defined there? Are there proper solder masks between the pins to avoid shortcuts? Did you make X-RAY checking of soldered devices?
We have checked the solder masks and they are all ok.
We measure the output pins and the GND pins, output and GND are shorted in UCD7242.
I think UCD7242 is very easy to be damaged when soldering in high temperature, is it right?
Can you tell me what is the best temperature for soldering UCD7242?
I see on the webside that LM10010 + TPS56121 can be used for C6678 CVDD,
Can I use that for our design in the future?
Thank you very much. Needing your quick reply.
Did you measure the pins on a PCB where the device is not mounted, to see if they are not shorted?
Did you check any device before soldering it, to check if the pins are not shorted, and to make sure that (apparently) the device is damaged when soldering it?
I don't know what do you mean by "high temperature", the device is RoHs compliant, but I am not an expert on soldering profile definition, you should check on TI site for that information.
http://focus.ti.com/quality/docs/gencontent.tsp?templateId=5909&navigationId=11749&contentId=5045
Thank you.