1. LHAASO Electronics developments
4th Workshop on Air Shower Detection at High Altitude
LHAASO Electronics developments
Yingtao CHEN, IPNO, France
for the LHAASO collaboration
Naples, Italy, February, 1st, 2013

2. Outline Introductions of LHAASO The PARISROC 2 ASIC
4th Workshop on Air Shower Detection at High Altitude
Outline
Introductions of LHAASO
The PARISROC 2 ASIC
The requirements of WFCTA
Results
Future plans and conclusions

3. LHAASO Large High Altitude Air Shower Observatory Detectors
4th Workshop on Air Shower Detection at High Altitude
LHAASO
Large High Altitude Air Shower Observatory
~ 4300 m a.s.l., Shangri-La, Yunnan, China
Detectors
KM2A, WCDA, WFCTA, SCDA
Main scientific goals
Survey of the gamma sky above 100 GeV
Search for CR origins among galactic gamma ray sources
Measurement of cosmic rays
Shangri-La
Airport
Possible Location
~ 20 Km

4. Challenges for electronics
4th Workshop on Air Shower Detection at High Altitude
Challenges for electronics
HV base AB DB
4x4 PMTs
Different requirements  Different electronics
High altitude  Low heat dissipation
Large number of channels  complexity of electronics
Compact design
High stability
High reliability
Easy to maintain
256 channels
We focused on WFCTA at first
The ASICs can be used to simplify the electronics for LHAASO
Prototypes in YBJ, Tibet

5. Photomultiplier ARray Integrated in SiGe ReadOut Chip
4th Workshop on Air Shower Detection at High Altitude
Technology: 0.35μm SiGe AMS
Photomultiplier ARray Integrated in SiGe ReadOut Chip
PARISROC 2 is designed by OMEGA Group
Dual-gain Preamplifiers
16 Channels (neg.)
Auto-trigger design
Charge measurement:
50 fC ~ 100 pC
Time measurement: tagging < 1 ns
10 bit ADC internal conversion
CQFP160
5 mm X 3.4 mm
15 mW / channel
278 slow control parameters
A very complex SoC designed for multiple purposes and experiments
Input range
-0.8 V to 4.1 V
S. Conforti Di Lorenzo et al., NIM A , arXiv:

6. 5 mm X 3.4 mm HV base DB AB Simplified block schematic PARISROC 2
4th Workshop on Air Shower Detection at High Altitude
Simplified block schematic
PARISROC 2
Each block is a complex structure
The decision of the slow control parameters is the crucial point and it is experiment-dependent.
5 mm X 3.4 mm
HV base AB DB
4x4 PMTs

7. Telescopes Electronics
4th Workshop on Air Shower Detection at High Altitude
Wide Field of view Cherenkov/Fluorescence Telescope Array (WFCTA)
The angular resolution: < 0.4°
The energy resolution: < 20%
The resolution of the location of shower maximum: < 40 g/cm2
The Field of View (FOV) of a single telescope: 14°X 16°
Dynamic range: 3 orders of magnitude of the energy
Movable design for different purposes
24 identical telescopes divided into 3 groups with a distance of 100 m
Telescopes
Signal polarity: Negative (Anode)
Dynamic range: 160 fC to 240 pC
Nonlinearity: < 2%
Charge resolution: < pe and pe
Time resolution: 20 ns (RMS)
Single channel event rate: 10 KHz
Signal width: 6 ns to 50 ns (Cherenkov)
Pedestal monitoring: Sky and electronics
Channels: 1024 per telescope
Power consumption: 260 W
Electronics
Prototypes in YBJ, Tibet

8. The mechanical requirements for the PMT array and the FEEs
4th Workshop on Air Shower Detection at High Altitude
The mechanical requirements for the PMT array and the FEEs
32 X 32 PMT array divided into 64 clusters
Active heat dissipation Schema
16 PMTs per cluster
Blowing Plant

9. The schema of electronics of WFCTA
4th Workshop on Air Shower Detection at High Altitude
The schema of electronics of WFCTA
Large number of channels
WFCTA: 1024 channels each
Heat dissipation at 4300m
Air density: 60%
Active heat dissipation system
Reliability & Maintainability
“SoC + FPGA” Design
FEE boards

10. The test bench of the ASIC
4th Workshop on Air Shower Detection at High Altitude
The test bench of the ASIC
PMM2 Test Bench for PARISROC 2
IPN-SEP, Orsay, France
Oscilloscope
Signal Generator
40V Power Supply
Multimeter
PMM2 Application Board
Attenuator
Signal Splitter
Black Box for PMT

11. 4th Workshop on Air Shower Detection at High Altitude
Results: signal width
Linearity < 0.3%
Linearity < 0.2%
Linearity < 0.1%
Linearity < 0.02%
Linearity: ~ 2%
Delay for signals with varied width
By choosing the slow control parameters, the width of the input signals can be increased to 50 ns.
LHAASO Technical Report, LHAASO-WFCTA-TECH-FR-IPNOLAL B,

12. Results: dynamic range of single channel with different gains
4th Workshop on Air Shower Detection at High Altitude
Results: dynamic range of single channel with different gains
1 mV ≈ 260 fC; 0.6 mV ≈ 1 pe ≈ 160 PMT Gain 106
LHAASO Technical Report, LHAASO-WFCTA-TECH-FR-IPNOLAL B,

13. Results: dynamic range of the combined channel
4th Workshop on Air Shower Detection at High Altitude
Results: dynamic range of the combined channel
1 mV ≈ 260 fC; 0.6 mV ≈ 1 pe ≈ 160 PMT Gain 106
LHAASO Technical Report, LHAASO-WFCTA-TECH-FR-IPNOLAL B,

14. Results: pedestal monitoring
4th Workshop on Air Shower Detection at High Altitude
Results: pedestal monitoring
External test input port HG LG
At least, Four points are needed to figure out two pedestals (HG & LG).
It is the easiest way to generate test signals by using FPGA.
Same width but different amplitudes
Same amplitude but different widths

15. Results: event rate The maximum event rate Performance Specification:
4th Workshop on Air Shower Detection at High Altitude
Results: event rate
The maximum event rate
Specification:
20 KHz (best case)
5 KHz (worst case)
Single channel
~ 130 KHz (TDC off)
~ 60 KHz (TDC on)
8 channels
~ 16.7 KHz
16 channels
~ 8.4 KHz (not related to the TDC)
Performance
Not related to
Width
Amplitude
related to:
FPGA
Event rate is limited by the performance of FPGA

16. Future plans I Base Design for CR303: CR303, IPNO 43 mm 25.4 mm
4th Workshop on Air Shower Detection at High Altitude
Future plans I
Continue further tests on ASIC
Event rate
Charge resolution
Sky background pedestals
PARISROC 2 + PMT tests
CR303 (Beijing Hamamatsu)
R1924 (Hamamatsu)
Base Design for CR303:
Single tube base for prototype
16 tubes base for telescope
25.4 mm
43 mm
CR303, IPNO
R1924A, IHEP

17. Future plans II Design a new FEE board TE0600-01 + TE0603-02
4th Workshop on Air Shower Detection at High Altitude
Future plans II
Design a new FEE board
2 PARISROC 2 + Spartan-6
Support sky background monitoring
Fulfill the mechanical and environmental requirements of the WFCTA
TE TE
Spartan-6 LX150: 147K
Size: 50 mm × 40 mm (half of a credit card)
10M/100M/1000M Ethernet
2 x 16-bit 256MB DDR3 SDRAM
128Mb (16 MB) SPI Flash
Robust board-to-board connectors (B2B) LSHM up to 10 GHz / 20 Gbps
Up to 52 differential I/O
Up to 109 single-ended I/O

18. 4th Workshop on Air Shower Detection at High Altitude
Conclusions
The ASICs are adapted for experiments like LHAASO at high altitude
The performances of the PARISROC 2 has been studied for WFCTA in Cherenkov mode
Signal width
dynamic range …
The PARISROC 2 fulfills most of the requirements of WFCTA in Cherenkov mode, but some tasks still need to be done in future
Current Plans:
PMT tests: Base for single tube & Base for16 tubes
New FEE: Fulfills the requirements of WFCTA with 2 PARISROC 2 + Spartan-6
This ASIC may be adapted for other detectors in LHAASO

19. Thank you for your attention!
4th Workshop on Air Shower Detection at High Altitude
Thank you
for your attention!