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Overview of What Was Done Last Week…. Worked with Alex M. to measure ALCT turn-on curves See next slides… Obtained values of currents for all on-chamber electronics components at point 5 See later slides…
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Overview of What Was Done Last Week… • Worked with Alex M. to measure ALCT turn-on curves • See next slides… • Obtained values of currents for all on-chamber electronics components at point 5 • See later slides… • Would like to finalize values to send to Valeri to implement “out of range” alarms in DCS… G. Rakness (UCLA)
Overview (cont.)… • Upgraded online software to make the flagging of configuration errors depend on the “problem_mask.” • If (configuration error != configuration error expected) then output is red • (Used to be: if (configuration error) thenoutput is red…) • Turned on full set of CSC’s underground today… • One OPFC+Maraton not working, to be addressed by Petr tomorrow… • Checked firmware on entire system… After Misha’s work, much firmware will need to be loaded… • Daily CSC commissioning phone meeting started (again) • +1-510-665-5437… Meeting ID = 2175 • 17h30 CERN time • There is also a DCS phone meeting at 17h00, ID = 5566… • Any interest in a public google calendar for CSC events? • I already have one, it is just a matter of making it public… G. Rakness (UCLA)
ALCT turn-on curves • Executive summary: • Features in scope traces understood • No “smoking gun” seen in traces to be a likely cause of blowing fuses on the ALCT • At the commissioning phone meeting Monday 26 January 2009, it was decided to power up the system as soon as we could… More scope traces and explanations can be found at… http://www.phys.ufl.edu/~madorsky/alctv/curves-explained.doc G. Rakness (UCLA)
1 3 5 2 4 1.8V current on ALCT as ALCT is powered on… • Blue = 1.8V current • Several features seen as the ALCT powers up… • Large current spike • 600msec of small current draw • 200msec of 500mA (full) current draw • ~30msec of small current draw • Full current draw • Features similar on 3.3V line… • To be explained on subsequent slides... G. Rakness (UCLA)
Powering-On the Peripheral Crate Recall: there is a specific sequence to the voltages which are enabled when we turn ON the peripheral crate… • Enable power to 1.5V… pause 150ms • For (TMB/DMB pair 1 to 9) • Enable pair… pause 150ms • N.B. When DMB powers on, it enables the power to the ALCT… • Additional pause 150ms • Enable Crate Controller… pause 100ms • Enable MPC/CCB • Clock on G. Rakness (UCLA)
Feature 1) Current spike during voltage ramp Powering on the DMB enables voltage to the ALCT. This charges up the bypass capacitors on ALCT (and capacitance of floating scope…?) ME+1/2/15 Yellow: 1.8V voltage (inverted) Blue: 1.8V current (50mV/div = 5A/div)… peak at ~30A Time scale = 200sec/div From this trace, I2T = 0.18 A2-sec at ALCT power-on… Rating of ALCT fuse (A. Madorsky) = 1.6 A2-sec The inrush of current at ALCT power-up is probably not causing fuses to blow… (similar for 3.3V line) G. Rakness (UCLA)
Features 2) and 3) Time between spike and large current Feature 2) The FPGA is idle until the CCB is powered on. Feature 3) When the clock is powered on, the FPGA programs… ME+1/3/28 Yellow: 3.3V voltage Blue: clock at ALCT The time between ALCT power-on and the clock depends on where the DMB is located within the crate… (The noise on 3.3V voltage curve [coinciding with clock] is due to the ungrounded scope.) G. Rakness (UCLA)
Feature 2) (detail) Hard resets seen as each TMB/DMB pair is powered on… • FPGA hard-resets are seen as each TMB+DMB pair is powered on… ME+1/2/15 Yellow – 3.3V power Blue – hard reset Magenta – INIT Green – DONE Note: all resets come when there is no clock, so they have no effect… G. Rakness (UCLA)
Features 4) and 5): after FPGA programmed, ~30msec current dip followed by full current • Dip in ALCT core current from ALCT FPGA reprogramming due to hard reset sent from CCB after its FPGA is programmed ME+1/2/15 Yellow – 3.3V power Blue – hard reset Magenta – INIT Green – DONE Note: This is an intentional feature of the CCB firmware… G. Rakness (UCLA)
All hard reset and clock features go away if DMB fully controls power-on… ME+1/3/28 Blue: 3.3V current Note: regular FPGA power up and configuration. The first ~30 ms of low power consumption is configuration time, then normal operation. No strange artifacts as seen with CRB turn on. Is it worth the effort to rework the power-on sequence to achieve this? Probably not… G. Rakness (UCLA)
Distributions of Current for On-Chamber Components Goal: to determine values beyond which the Detector Control System (slow controls) should raise an alarm G. Rakness (UCLA)
On-chamber Currents ALCT Data from LVDB read through DMB using XMAS monitoring (J. Liu) Values consistent with values in DCS database (X. Yang) ALCT288 ALCT384 Red lines indicate (update to) proposed high/low alarm set points for DCS… (1.8V current has been lowered from 0.4A 0.3A) G. Rakness (UCLA)
On-chamber Currents ALCT and CFEB ALCT672 CFEB … if current limits for ALCT are OK, I will send to V. Sytnik to implement after this meeting… G. Rakness (UCLA)
13 Chambers Outside of ALCT Limits • 4 cases: ALCT's which have been or will be replaced • either from a blown fuse or some other problem... • 4 cases: exhibit the “smoking gun” of an EEPROM losing its program, i.e., a bit going from 1 0 • 1.8V current ~0.1A • 4 cases: looks like a "bad read" • read 0 on both 1.8V and 3.3V line • I believe we should not error on these, but read the values again... OR, we need to read the ALCT ADC as well as the LVDB currents... • 1 case: not known • Low (non-zero) values on both 3.3V and 1.8V lines • Maybe we need to read the ADC as well as the LVDB currents... Oftentimes, when it is bad on one line, it is bad on the other: • ALCT288: 5 chambers bad... 3 bad on both 3.3V and 1.8V criteria • ALCT384: 4 chambers bad... 2 bad on both 3.3V and 1.8V criteria • ALCT672: 4 chambers bad... 2 bad on both 3.3V and 1.8V criteria G. Rakness (UCLA)
To do • Continue towards getting a cosmic ray run going at point 5 • Attempt to measure time-of-flight in beam-halo or CRAFT data… • Upcoming talks: • CSC Trigger Primitives at L1 Trigger Online Software Review (Thursday 5 Feb.) • RAT results at RPC Detector Performance Group meeting (Tuesday 3 Feb.) G. Rakness (UCLA)
Backup G. Rakness (UCLA)
Probe Measurement Locations (ALCT288 schematic) Curves measured with floating scope… = voltage measurement drop points ( current)… Current curve behavior seen by measuring voltage drop across (fuse+10m resistor) at power-supply input with 20MHz bandwidth filter = voltage measurement point… Voltage curves measured at power-supply input relative to ground of chamber (full bandwidth) G. Rakness (UCLA)
3.3V current when power-on the DMB (ALCT) ME+1/3/28 3.3V current spike with CRB turn on Yellow: 3.3V voltage (inverted) Blue: 3.3V current (50mv/div = 5A/div) Similar behavior as on the 1.8V line… G. Rakness (UCLA)