28 Jan 2009 G. Rakness (UCLA) 1/15

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…

28 Jan 2009 G. Rakness (UCLA) 2/15

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) then output 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…

28 Jan 2009 G. Rakness (UCLA) 3/15

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

28 Jan 2009 G. Rakness (UCLA) 4/15

1.8V current on ALCT as ALCT is powered on…

Blue = 1.8V current

Several features seen as the ALCT powers up…

1) Large current spike

2) 600msec of small current draw

3) 200msec of 500mA (full) current draw

4) ~30msec of small current draw

5) Full current draw

Features similar on 3.3V line…

To be explained on subsequent slides...

1

2

3

4

5

28 Jan 2009 G. Rakness (UCLA) 5/15

Powering-On the Peripheral CrateRecall: 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

28 Jan 2009 G. Rakness (UCLA) 6/15

Feature 1) Current spike during voltage ramp

Yellow: 1.8V voltage (inverted)Blue: 1.8V current (50mV/div =

5A/div)… peak at ~30ATime 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)

ME+1/2/15

Powering on the DMB enables voltage to the ALCT. This charges up the bypass capacitors on ALCT (and capacitance of floating scope…?)

28 Jan 2009 G. Rakness (UCLA) 7/15

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…

Yellow: 3.3V voltageBlue: 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.)

ME+1/3/28

28 Jan 2009 G. Rakness (UCLA) 8/15

Feature 2) (detail) Hard resets seen as each TMB/DMB pair is powered on…

Yellow – 3.3V powerBlue – hard resetMagenta – INITGreen – DONE

Note: all resets come when there is no clock, so they have no effect…

ME+1/2/15

• FPGA hard-resets are seen as each TMB+DMB pair is powered on…

28 Jan 2009 G. Rakness (UCLA) 9/15

Features 4) and 5): after FPGA programmed, ~30msec current dip followed by full current

ME+1/2/15

• Dip in ALCT core current from ALCT FPGA reprogramming due to hard reset sent from CCB after its FPGA is programmed

Yellow – 3.3V powerBlue – hard resetMagenta – INITGreen – DONE

Note: This is an intentional feature of the CCB

firmware…

28 Jan 2009 G. Rakness (UCLA) 10/15

All hard reset and clock features go away if DMB fully controls power-on…

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…

ME+1/3/28

28 Jan 2009 G. Rakness (UCLA) 11/15

Distributions of Current for On-Chamber Components

Goal: to determine values beyond which the Detector Control System (slow controls) should raise an alarm

28 Jan 2009 G. Rakness (UCLA) 12/15

On-chamber Currents ALCT

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)

Data from LVDB read through DMB using XMAS monitoring (J. Liu) Values consistent with values in DCS database (X. Yang)

28 Jan 2009 G. Rakness (UCLA) 13/15

On-chamber Currents ALCT and CFEBALCT672 CFEB

… if current limits for ALCT are OK, I will send to V. Sytnik to implement after this meeting…

28 Jan 2009 G. Rakness (UCLA) 14/15

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

28 Jan 2009 G. Rakness (UCLA) 15/15

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.)

28 Jan 2009 G. Rakness (UCLA) 16/15

Backup

28 Jan 2009 G. Rakness (UCLA) 17/15

Probe Measurement Locations(ALCT288 schematic)

= voltage measurement point… Voltage curves measured at power-supply input relative to ground of chamber (full bandwidth)

= 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

Curves measured with floating scope…

28 Jan 2009 G. Rakness (UCLA) 18/15

3.3V current when power-on the DMB (ALCT)

3.3V current spike with CRB turn on

Yellow: 3.3V voltage (inverted)Blue: 3.3V current (50mv/div =

5A/div)

ME+1/3/28

Similar behavior as on the 1.8V line…