1. Zhang Ying briefly summarize the status of the pixel analog design. One more week may needed to begin the layout. She suggested we should start the design of IO pads with negative biasing, and we can refer to the MIC4 design in MOST1.
2. Concerning the possibility to use the modified Tower Jazz process, now we still don't have the final answer yet. Several take away message were:
2.1 We will tapeout our first MPW chip in March~April 2019. This will follow the same schedule from IPHC. We have to catch up this train otherwise the tapeout will be greatly delayed and we will fall behind the whole project schedule.
2.2 We should further contact with both Walter and Christine for the tapeout schedule, and the possibility for using modified TJ. Wei Wei will contact Christine very soon to first claim a necessary area in the scheduled tapeout.
2.3 Although we don't have the final word for the use of modified TJ from Walter, we will keep our design on normal TJ for this first tapeout. For the reason that, first the electronic design is not sensitive to the normal/modified TJ, and can be easily switched. Second, we should first evaluate the major functionality of our circuit. Third, the modified TJ may be modified further, and we can wait till then.
3. Tianya gave some simulation results concerning the pixel array parasitic and delays. For the delay, now the worst case of TDA seems to be larger than 1 clk (25ns) but less than 2 clks(50ns). It seems still not a fatal issue because we read out every pixel with 2 clks. However, TDFOR will be in the same range as TDA(>1clk), which might cause some problem. Tianya will send Wei xiaomin of the correct value (TDFOR in the slides was not correct) of all the delays for a further evaluation.
4. Daniel and Yanyan joined the discussion and expressed the willing for collaboration. Possible area may be the sensor evaluation and radiation damage study. Daniel suggested that for the sensor TCAD simulation, we should find a contact person from the Tower Jazz foundry to get a precise value of the doping profile and so on. This will help a lot for the sensor TCAD simulation. However he thought Tower Jazz seemed not so open as other foundries like LFoundry. We will discuss further to find possible start point for the collaboration.
5. Weiguo reported some bugs currently found from global simulation.
One is the incorrect polarity of output signal from pixel analog to digital. An inverter has to be added, and this has been corrected by Tianya.
The other problem is, when the pixel analog output is valid and the "read" is continuously provided, the same pixel will be reportedly readout. Actually the pixel analog can hardly be reset by digital pulse, so we has to find a solution for this problem.