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Entry  Wed Dec 23 15:38:14 2015, mony orbach, Dtap stops toggling after 40msec 
    Reply  Wed Dec 23 15:48:42 2015, Stefan Ritt, Dtap stops toggling after 40msec 
       Reply  Thu Dec 24 10:51:31 2015, mony orbach, Dtap stops toggling after 40msec 
          Reply  Thu Dec 24 12:45:41 2015, Stefan Ritt, Dtap stops toggling after 40msec 
             Reply  Sun Dec 27 15:41:32 2015, mony orbach, Dtap stops toggling after 40msec Dtap-Denable.gifdtap-Danable2.gifDtap-refck.gifDtap-Dspeed.gif
                Reply  Mon Dec 28 11:05:15 2015, Stefan Ritt, Dtap stops toggling after 40msec 
                   Reply  Mon Dec 28 11:21:54 2015, mony orbach, Dtap stops toggling after 40msec 
                      Reply  Wed Dec 30 16:25:35 2015, mony orbach, Dtap stops toggling after 40msec 
                         Reply  Wed Dec 30 17:00:00 2015, Stefan Ritt, Dtap stops toggling after 40msec 
                            Reply  Thu Jan 14 14:00:26 2016, mony orbach, Dtap stops toggling after 40msec 
                               Reply  Thu Jan 14 14:11:06 2016, Stefan Ritt, Dtap stops toggling after 40msec 
Message ID: 465     Entry time: Wed Dec 30 16:25:35 2015     In reply to: 464     Reply to this: 466
Author: mony orbach 
Subject: Dtap stops toggling after 40msec 

Hi

We have resolve the problem, the Dtap is now working correctly.

There were two problems:

  1. After configuration we put the all address bits to one (standby mode)

We are now setting the address bits to all zero. Failure

to do so result in Dtap  stop toggling after several hundred milliseconds.

  1. The DMODE bit in contradiction to the data sheet should be set to 0

And not to 1.

 

Is this a known bug in the chip?

Only bay setting DMODE to zero we got the Dtap to work correctly.

The PLL locks after 1 milisec.

If we set it to one we get Dtap that stop toggling after several hundred milliseconds.

We have test it on two boards, they both worked in the same.

Never did we get a One shot  Dtap.

 

Did you published a errata page to the drs4?

 

 

Thanks, Mony

 

mony orbach wrote:

Hi Stefan

Thanks for your input.

We are in the process of assemble another PCB board.

so soon we can compere between two boards.

As for the PLLEN bit, we set it.

We checked several times the soldering of the DRS4 using a microscope.

Everything looks ok.

In what method do you recommend to solder the DRS4?

 

Thanks for the invitation to meet.

120Km is not so far J

 

mony

Stefan Ritt wrote:

Thanks for posting the plots. It really looks like the PLL is not working. I see two possible reasons: 1) The PLLEN bit in the configuration register is not set and 2) The REFCLK signal does not reach the chip. We had cases whrere people had a hard time to solder the DRS4 correctly due to the small pins. So if the REFCLK+ and REFCLK- signals have a poor connection, then the PLL of course won't work. Putting some more tin at the pins manually usually helps. Or remove the chip completely and try with another chip. In theory there is the possibility that the internal bond wire of the REFCLK signal has a bad connection, but we tested all chips we send out so we should have seen that. But trying with another chip cannot hurt in general. Next month I'm coming to the Weizman Institute for the ISOTDAQ shool. If you want we can meet there if you don't mind the 120 km drive from Haifa.

Stefan

mony orbach wrote:

Hi

We have some measures to show (attached)

  1. Dtap and Denable
  2. Dtap+Denable in zoom
  3. Dtap + Refck+
  4. Dtap + Dspeed

From the screen shots it can be seen that refck+ is not synchronized with Dtap (PLL not working correctly)

And Dspeed is going done to zero after some time.

In our system Dspeed is shorted to pllout.

So it looks like pllout do not pump the RC filter capacitors.

We tested various value of R and C's.

Also we checked that pllout is sorted to Dspeed.

 

Thanks, mony

 

 

 

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