1. Power pulsing of AFTER in magnetic field
D. Attié, P. Colas, E. Delagnes, M. Riallot
M. Dixit, J.-P. Martin,
S. Bhattacharya , S. Mukhopadhyay
I’m here to present a TPC review
Linear Collider
Power Distribution & Pulsing Workshop
May 10th, 2011

2. May 10, 2011 - LC Power Distribution and Pulsing Workshop
Introduction
Proposal:
Use existing electronics and adapt it for power pulsing to read out the detector pads:
Integrated T2K electronics
Having a two power states: low and nominal
Switching between state as fast as possible
In parallel, use constant current charging circuits to readout the detector mesh (see J.-P. Martin’s talk)
Using an 55Fe source to monitor the signal and gain
Operating in 5T magnet in DESY
May 10, LC Power Distribution and Pulsing Workshop

3. AFTER-based electronics
AFTER chip (72 channels/chip) from T2K experiment:
low-noise (700 e-) pre-amplifier-shaper
full wave sampling by SCA (511 time bins)
120 fC to 600 fC tunable gain
100 ns to 2 μs tunable peaking time
pulser for calibration
25 W, 5V at 5 A (0,5 W/chip)
1 FEM, 6 FECs, 24 chips :1728 ch
12-bit ADC, 6 channels multiplexed
Zero Suppression capability (FPGA)
~14-25 mW/channel
AFTER chip wire bonded
FEC
May 10, LC Power Distribution and Pulsing Workshop

4. Front-End Mezzanine (FEM)
30 pins
connector
FPGA
Xilinx V5
ADC
SRAM
Test Pulser
Xilinx
Prom
Optical
AFTER
May 10, LC Power Distribution and Pulsing Workshop

5. Design of the integrated electronics
May 10, LC Power Distribution and Pulsing Workshop

6. Electronics in DESY 1T magnet
Picture and events taken last week in DESY with electron beam
1726 pads read out by the AFTER-based electronics
Power consumption of 25W was measured and confirmed
Large prototype TPC
3 GeV electron Beam
May 10, LC Power Distribution and Pulsing Workshop

7. May 10, 2011 - LC Power Distribution and Pulsing Workshop
Project design
DESY 5T magnet has to be reinstalled
Endplate ø 32 cm
Field cage length not yet defined
1 FEM and 4 FEC to readout 1136
pads of 3,7×3,7mm² E B
May 10, LC Power Distribution and Pulsing Workshop

8. May 10, 2011 - LC Power Distribution and Pulsing Workshop
Readout Pads
16 independent HV connections read out by constant current charging system
May 10, LC Power Distribution and Pulsing Workshop

9. Low power state conditions
Specific firmware of the for the FPGA Xilink 5 will be done
Switch on and off the regulator TPS for powering 3.3 V: t<1 ms
May 10, LC Power Distribution and Pulsing Workshop

10. May 10, 2011 - LC Power Distribution and Pulsing Workshop
Summary of the plan
Try power switching on both the (segmented) mesh readout as studied by Jean-Pierre Martin (see the next talk) and the T2K electronics
For T2K electronics, power switching might be done on the mezzanine card (FEM) developed for the 7-module configuration of the Large Prototype Micromegas TPC
The test will consist in checking the properties of known X-ray lines with and without pulsing
The mechanical effects will be studied by having a large enough number of channels (1200) and a large magnetic field (5T) close to realistic conditions
May 10, LC Power Distribution and Pulsing Workshop