FP420 Low and high voltage supply

1. FP420Low and high voltage supply Henning E. Larsen, INFN Henning.e.larsen@gmail.com Dec. 2006. rev.2

2. Revision information • Since I made the slides, the frontend has gone from 6 to 4 detectors/superlayer. I have as far as possible tried to take this fact into account in this revised version.

3. 1 Superlayer = 2 Hybrids/Blades 4 2D detectors 1 MCC 1 Read-out interface HV-LV supply segmentation PT1000 Temperature sensor? Now only 2 det. Damage depends on distance from the beam. Required bias voltage and current increase with radiation dose. Pixels:50x400um and 400x50um MCC: Module Controller Chip Drawing: From Ray Thompson

4. Specification for LV for 1 superlayer Ripple at 1MHz is critical. Remote on/off. Monitor current. Digital supply for Pixelchip and MCC is common as seen from supply. DEC 2006:Notice change from 6 to 4 detectors per superlayer

5. Specification for HV supply DEC 2006: Notice change from 6 to 4 detectors per superlayer Voltage is negative, but floating. Referenced to AVDD on PIXELCHIP, not GND (*) -120V is also sufficient. HV connection diagram used in Atlas Source: Maurice Garcia-Sciveres

6. One of 4 stations Crate count is preliminary Counting inventory: Super layers: 2 experiments * 2 zones * 5 pockets * 5 superlayers=100 super layers LV supplies: 100 super layers * 2 voltages = 200 channels HV supplies: 100 super layers *2 voltages = 200 channels

7. Overall system geography

8. Confidential Commercial: Wiener solution A Mpod x 8 4*2 Mpods with 80ch each. Location: Counting room • 150k€ for Mpod’s • 100k€ for cables • 2x4 Mpod-like systems (8U,19” each) will be arranged to provide the requested voltages over 500 m distance, • Located in the counting rooms and will host both HV and LV modules. • 2 cable pipes with 10 cm section (or probably less) are needed. • The Mpod will require custom -150V modules. . Now only 2 HV Now only 2 HV

9. 1 Maraton 1 Maraton Confidential Commercial: Wiener solution B One per crystat One per pocket One per pocket Mpod x 2 x 5 • 2x10 Maraton-like radiation tolerant systems (3U) will provide LV and operate close to the detectors. • 2x2 Mpod-like devices will supply HV from the counting rooms. • This solution requires a customization of Maraton in order to optimize it for low currents. • The Mpod will require custom -150V modules. • Cost not yet discussed. Now only 2 HV

10. 1 Maraton 1 Maraton Confidential Commercial: Wiener solution C 2.2 crates per pocket 2.2 crates per pocket x 11 x 11 • 2x22 Maraton-like system will provide HV and LV and operate close to the detectors. • Simple cable • These systems will be optimized for the given current range. • Need customization for -150V modules • Proven radition tolerance: 722Gy, 8 1012n/cm2 • Cost not yet discussed H=3U=131mm Now only 2 HV

11. A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3009 12ch LV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV A3501 12ch HV EASY 3000 EASY 3000 EASY 3000 EASY 3000 FP420 pocket FP420 pocket FP420 pocket FP420 pocket FP420 pocket FP420 pocket FP420 pocket FP420 pocket FP420 pocket FP420 pocket Confidential Commercial: Caen CMS/Atlas counting room Atlas or CMS Slow control SY1527 A1676A Crate Ctl A3486 2x48V Power A1676A Crate Ctl A3486 2x48V Power LHC Tunnel Cryostat 1 Cryostat 2

12. Commercial: Caen, pictures SY1527 EASY 3000 A3501 A3009 Not to scale

13. Confidential Commercial: Caen Cable: 500m A3009 LV A3501 HV A3009 LV A3501 HV A3486 48V Power • Modules 220k€ • Cable ~20k€ • Delivery not possible before summer 2008 due to LHC production bottle neck. Only few samples by mid 2007. • CAN bus link has to be extended to 500m. This is not yet tested • High voltage only up to 120V

14. Confidential Commercial: EplaxGmbH • Entirely custom design based on their >20year experience with standard power supplies and our specification • No experience with radiation tolerant supplies. • Non recurring engineering cost: 25k€ • Supply for 1 superlayer: 900€ • Total cost: 115k€ (excl cables)

15. LV supply: simulation model with long lines • Simulation shows a 500m+500m cable with 20% current change for C=1µ, 5µ, 50µF • Current transients are mainly limited by capacity at the load. • Conclusion: • 500m++ of LV cables is not feasible

16. Simulation, Low voltage, 500m cable

17. LV supply using LHC4913 • If we make our own custom solution a regulator like LHC4913 is very convenient and unique. It is now being ported to a military/space qualification => higher cost, but presumably available. • Rad hard. • Extensively used at LHC detectors. • Remote sense on the positive and negative supply. This means it can compensate for resistive cable voltage drop. This means that with LHC4913, a thinner cable can be used. • Adjustable current limit. • ON/off switch input.

18. ADC’s: DCUF Detector Control Unit (CMS) • CMS central tracker for the monitoring of some embedded parameters like supply voltage and currents on the front-end read-out modules • Is available in the quantity we need

19. HV principle diagram Cable Ibias R3 Pass transistor R2 R2 Vin αIbias + Vbias - Transformer+rectifier αVbias R1 R1 ADC’s Galvanic isolation DAC • Simple linear regulator to make radiation tolerance easier to implement with COTS • Monitor, remote control, galvanic isaolated

20. Confidential “Home made” in-tunnel-solution cost estimate Modules 120k€ Cable 20k€

21. Location for service electronics Until today we thought: • If the LV electronics should stay within some 20m from the detectors, there are only two possible locations (ref Daniela Macina): • Below the new cryostat, where the radiation level is estimated at about 700 Gyper year of running at full luminosity; • Below or near the adjacent magnets, where the radiation is much lower and estimated at about 15 Gy per year, but where there are already other things. At mechanics meeting 29/9/06 we saw: • Space for service electronics. • Few meters of cable • Radiation level? • Shielding possibility? FP420 detectors Space for electronics needing close proximity to detectors

22. Issues to finalize • Location of support electronics in tunnel. Favour of putting it under the adjacent magnets. Cable length about 10m. • Radiation level to expect. There ought to be simulations done with shielded cryostat at fp420 to evaluate the dose. Current assumption is 15GY/y • Home made or commercial solution? • Cable distances from fp420 to the counting room for all 4 stations have to be estimated more precisely than the current 500m • Specification of number of channels • Specification of LV supply for superlayer readout part (Opto board). • Need for temperature monitor of FE for the cooling system. Where should it be serviced? If in the HV-LV unit, we need define a local interface with cooling as this cant go through slow control. • Are there any requirement for: • Hardware interlocks related to temperature? • Graceful power down =UPS backup?

23. Conclusions • Some interesting solutions from industry. Some almost off the shelf. • We have an outline of how to build the LV-HV our selves but chip supply is critical. • We need to make up our minds if we buy or build ourselves. • We are opting for putting the LV/HV crates under the adjacent magnets