1. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 1 Thermal Testing of TOB/TEC Hybrids at UCSB

2. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 2 The CMS detector will run at –20 C in order to lessen radiation damage to the silicon Why Thermal Test?

3. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 3 Why Thermal Test Hybrids? Some Hybrids fail at –20 C –APVs do not output –Hybrid fails to initialize –Noise increases in cold (peltier current?) APV: Analog Pipeline Voltage Mode Chip

4. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 4 Set-up in Clean Room

5. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 5 Cooling Down How long should/does it take to get to –20? Cold chamber Peltier + Plate Chiller Air Air Flow (0.05 L/min) Water Flow (14 L/min)

6. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 6 Simplifying things S= surface area of enclosure (m ) k=thermal conductivity of walls (W/m C) h=convection factor (W/m C) x=thickness of walls (m)

7. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 7 Calculating time to -20 First order linear differential equation: Solution: (T(t=0)=295K)

8. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 8 Not quite… Calculation says that plate should reach –20 in ~14 minutes. Actual time: ~21 minutes Possible problems: Unaccounted heat influx through leaks or grounding strips connecting plate to outside Assumptions made are flawed Missing term in differential equation

9. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 9 Interfacing to a PC: ACDC

10. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 10 Testing Software: ARCS APV Readout Control Software Communicates With ACDC via TCP/UDP

11. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 11 What are we testing for? Shorted channels: On each clock, charge injected into every 8 th channel. Shorted channels share, ADC amplitude is diminished. 128 Channels per APV -6 APV hybrids: 768 -4 APV hybrids: 512

12. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 12 What are we testing for? Open Channels: Inject charge through Capacitive coupling of pitch adapter to antenna carrying TTL Pulse Antenna Pitch Adapter

13. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 13 With Pulser Operational…. Opens are also detectable in Pedestal & Noise Test Plucked Bonds

14. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 14 Thermal Cycle Test “One Button” test Three Sets of Tests: Pedestal & Noise Pulser Short Detection

15. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 15 Automated Test Results Final Report After Thermal Cycle Test: Lists -Shorts -Opens -Noisy Channels

16. Thermal Testing of TEC/TOB Hybrids at UCSB 1/20/04 Slide 16 Testing & Replicating UCSB Cold Box ready for full scale testing: ~28 hybrids per day Fermilab Cold Box near completion Mexico City Cold Box next on the list