FP420 Tracker and Timing detector Low and high voltage supply INFN/Univ. of Torino Cern meeting, Jan. 2009

Distances involved

HV-LV supply segmentation Damage depends on distance from the beam. Required bias voltage and current increase with radiation dose. Drawing: From Ray Thompson PT1000 Temperature sensor? Pixels:50x400um and 400x50um MCC: Module Controller Chip 1 Superlayer = 2 Hybrids/Blades 4 2D detectors 1 MCC 1 Read-out interface

Specification for LV for 1 superlayer 1 Pixel FE-I3Voltage rangeVoltage nom.Current rangeCurrent limit Analog V1.6V5-70mA100mA Digital V2.0V1% occupancy: 40-50mA 10% occupancy: 60-70mA 100mA MCC/1VoltageCurrentCurrent limit Digital V120mA-150mA170mA Ripple at 1MHz is critical. Remote on/off. Monitor current. Digital supply for Pixelchip and MCC is common as seen from supply. 4 FE-I3 Chips + 1 MCC + Read-out? Voltage range Current rangeCurrent limit Analog V20-280mA310mA Digital V1% occ 280mA-350mA 10% occ 360mA-430mA 480mA Monitor resolution<20mV<10mA

? What about the readout optoboard. Does this not need power? Up till now this was not considered!

Specification for HV supply for one superlayer 4 detectors 2 voltages VoltageCurrentCurrent limit V<1mA1mA Monitor Resolution <1V1μA Voltage is negative, but floating. Referenced to AVDD on PIXELCHIP, not GND HV connection diagram used in Atlas Pixelchip FE-I3 Source: Maurice Garcia-Sciveres

Channel count This needs update! What about the optoboard. Does this not need power?

L4913 rad hard regulator nr. count DetectorNameVoltageCurrentOne cryostat LHCNote TrackerAVDD1.6V<280mA1040 TrackerDVDD2.0V<430mA1040 TimingDV3.33.3V1A28Approxi mate TimingAV A28Approx. TOTAL96

Power requirement summary

RR13 Tunnel Sector FP420 rack in part of one 1.6m high rack From: D. SWOBODA

Location for service electronics in tunnel Space for service electronics. 5 to 10m of cable Radiation level, 700Gy/y, 20MeV 1x10 12 /cm 2 /y Shielding possibility but not really efficient Space for electronics needing close proximity to detectors FP420 detectors Space for HV LV under adjacent magnets Height available=400mm Cable length to FE is about 20m Radiation level, 10 to 100Gy/y, 20MeV 1x10 10 /cm 2 /y

Solutions considered b) Adj. Magnets MB11a,b c) RR alcoves (LV) HV in CR d) Counting room

Local linear regulator to stabilize load voltage Monitor of load current by the power supply Monitor of the load voltage by sense wires and separate adc No remote adjustment of load voltage! Is that a serious problem? GND current in L4913 is rather high and varies. This means sense wire should not be too thin (Note from Z. Hajduk)

Solutions studied Location of LV supplies a)Next to pocket (700Gy/y, h > 20 MeV = 1x10 12 cm -2 /y) b)MB11a,b, under adj. Magnets (10G/y, h > 20 MeV = 4x10 10 cm -2 /y) c)RR alcoves (0.5Gy/y, h > 20 MeV = 1x10 8 cm -2 /y) d)Counting Room (0 Gy/y) CAEN EASY3000: b), c) Wiener –Marathon: b), c) –MPOD: c) Brand X in counting room: a)+d) a)Require either only passive (Patch-panel) or fully graded rad-hard electronics b)Require radiation tolerance and good SEU resistance. c)Require radiation tolerance and some SEU resistance and linear rad hard regulators at FE d)Standard high quality floating powersupplies and linear regulators at FE

Recommendation Recommends the solution with all complex electronics in the counting room and (LV) linear regulators next to frontend. Thus having 500m supply cables for both HV and LV. Power supplies are floating output. Shield and reference gnd at detector end only. In the counting room, Transorbers (zeners) connected from screen to chassis/earth for safety. Linear rad-hard regulators available from Cern stores for 2V, 3.3V and +5V supplies Solution for +-12V for Timing detector is being investigated

All supplies in counting room: Advantages/disadvantages Best access Most reliable No radiation to sensitive electronics Uses standard non rad-tol. power modules –cheaper, spares readily available Large cable cost More difficult to test as the EMC environment is hard to predict Custom design and test of linear regulator board No remote adjustment of low-voltages

Cable bundle, one station = two pockets+Quartic/Gastof

Issues with Timing detector regulators for +-12V Radhard LHC4913/7913 from CERN stores not suitable for +-12V so we need alternative: Intersil HS-117, +12V 1.2A –Constructed with the Intersil dielectrically isolated Rad Hard Silicon Gate (RSG) process –rad-hard to 3kGy, latch-up immune –Test report: Still missing -12V candidate devices

Further actions Setup a test to validate the supply over 500m of cable. Find a suitable solution for timing detector’s +-12V supplies. But seems that this may not be needed after all! Find a suitable power supply for use in the counting room. Many options available.

Commercial: CAEN module pictures SY1527 EASY 3000 Not to scale A Maraton A3501 Commercial Wiener module pictures MPODMaraton

Radiation levels - summary 6/12/2008Forward Physics at the LHC23 LocationDistance from IP [m] Dose [Gy] h > 20 MeV [cm -2 ] 1Mev Eq. [cm -2 ] Q622013x10 8 2x10 9 RR13,17,53, x10 8 1x10 9 Q x x10 12 FP420 space x x10 13 MB11A400 about(HL)12*10 (HL)4x x10 11 MB11B400 about(HL)103x x10 11 Annual levels for nominal LHC Source: T. Wijnands, TS Department

RELEVANT REMARKS FROM THIJS WIJNANDS If CAEN power supplies are put next to the stations below magnets:  Nr. SEU/module/day ~ 0.1  Single-event upsets (SEU) start from day-one. Control system that allows automatic reset of a module without changing the output voltage is needed (like LHC power converters).  Failure due to accumulated dose Gy (typical of transistors)

Maraton system overview

SPACE IN RR ALCOVES According to Detlef SWOBODA it may be feasible finding space for our crates in alcoves at 250 m from the interaction point also used by Totem for power supplies. (RR17/13 for Atlas and RR57/53 for CMS). - dose/year: (Totem data) <1Gy, 1e9 n/cm2, 1e8 h/cm2 - neutron flux ~ 10 8 n/cm 2 /y (factor 100 less than at the detector station) If this is true probably other irradiation tests not needed