Minutes of the Tracker Electronics Meeting June 12, 2000 Present: David, Robert, Hartmut, Masa, Dieter, Gunther, Vallon, Wilko, and Tsune Agenda: 1. Dave & Deiter: status of amplifier/discriminator design; SEU hard cell Dieter: He is working on an AC coupled discriminator design. The purpose is to remove all DC offsets caused by the shaper circuit. He has a design that he is happy with that uses a baseline restore circuit. He said that the simulations look good. Dieter: He has the cell design for the SEU hard cell from Ned and he says he understands how it works. He has not done any other work on this design. 2. Ned & Vallon: status of layout issues Robert reported for Ned: Ned has started working with the Tanner layout tools. He is making good progress understanding how the tools work. He is learning about scaling cells. Ned looked at what Vallon has done. He is working out how to proceed using Lambda grids so the design can be ported to different size geometry. The original chip was done on a 0.1 micron grid using lambda=0.4 micron SCMOS-SUBM design rules. Therefore, it should be possible to port it into Tanner using a 0.25-lambda grid and then define lambda to be 0.3 microns to achieve the scaling needed for SCMOS-SUBM in the new 0.5-micron process. A 0.25-lambda grid would also be commensurate with the 0.5-micron grid used in the Tanner standard-cell library. Dieter: He stated that he had used the Magic layout tools and not Tanner. 3. Wilko: BTEM testing status and status of single-chip test module. Wilko: He has set up the test board with a single front-end chip and controller chip. He now can take data very quickly. Wilko wants to spend a few days measuring the test board then go back and work on the BTEM readout noise problems. Wilko stated he would like the new controller from James by the end of this week. He plans to use a PC with a National Instruments interface. He stated that he anticipate no problems with getting the software going. Wilko also reported that it takes about 10 minutes to switch between the two systems (re-cabling). 4: Masa & Tsune: SEL test setup Masa: The new PC board is completed. He has measured gain and pulse shape. He will build a second board to test latch-up. The plan is to use a resistor in the power supply line to the chip and use a Keithley supply to monitor the current. Masa stated he will need three supplies but Robert thought that one would work fine for this initial test since the chip can run (at higher power) with a single analog supply, and there isn't much digital circuitry on the chip. The first tests will be done using the IR laser. This test will take about 1-2 weeks. Hartmut stated that we might be able to do some future tests at the LBL cyclotron. Hartmut stated that he will look into it. Action Items from June 5 Electronics meeting: 1. Masa and Tsune: set up a test chip with a resistor in series with the power and test for latch-up with a laser. This is in progress 2. Wilko: try running the PMT supply connected to the tower and do noise scans. No action 4. Dave: find specs for the BaBar SVT power supplies. Dave has the specifications from Mark Nyman. 5. Dave: talk to Roger about making more TEM boards. 6 PC boards are being fabricated. One is currently being loaded. Four more will be loaded when parts arrive. 5. Vallon and Ned: investigate whether the existing lambda=0.4um layout can be rescaled to 0.3um and imported into Tanner LEdit. They both have started the investigation. New Action Items: 1. Dave & Dieter: send the new front-end schematic to Robert and Ned. 2. Hartmut: look into the possible use of the LBL cyclotron for SEL testing.