1. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20071 DES MONSOON LINEAR POWER SUPPLY SELECTION Todd Moore University of Illinois, at Urbana-Champaign

2. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20072 Vicor Power Supplies Positives –Small Packaging Will fit in same package as DHE –Efficient Efficiency is around 80% –Built-in control circuitry Output overcurrent protection Independent enable/disable for each voltage Negatives –Less understood –Larger output ripple than Linear (10 mV p-p) 2 VICOR SUPPLIES 2 DHEs

3. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20073 Additional Testing Move Vsub (+48 volts) over to Vicor, so all voltages/returns come from Vicor supply Ramp voltage down on Vsub, then clamp outputs to a clean low impedance source –P. Moore says Vsub controls the major current path between clocks & output stage of detector, thus any cap. coupled currents from clocks will influence the reference for the output amps Apply High Volts DC (100-300VDC) to input of Vicor Understand what influence each sub-component of DHE (i.e. CCD Acq. video channel, CBB clocks, etc.) plays in the system noise. UofI has started this. Any other ideas? Otherwise use Linear supplies

4. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20074 Linear Power Supplies Positives –Very low output ripple voltage –Well understood solution Negatives –Large packaging Will not fit in same package as DHE –Not very efficient Efficiency is around 65% –No Internal Monitoring/Control circuitry More design time

5. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20075 Alternative Approach Use linear supplies mounted at the opposite end of the cage from the DES Monsoon DHE

6. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20076 Determining Cable Lengths

7. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20077 Power Cable Sizes and Lengths With 12 AWG power cable for all voltages –10 feet long Heat Load from cable bundle for 6 DHEs = 50 WATTS!! Total Diameter for 1 bundle, unshielded (x16) going to 1 DHE =.6” Total Diameter for 6 bundles, unshielded (x96) going to 6 DHEs = 1.8” With 8 AWG power cable for all voltages –10 feet long Heat load from cable bundle for 6 DHEs = 18 WATTS!! Total Diameter for 1 bundle, insulated, unshielded (x16) going to 1 DHE = 1.2” Total Diameter for 6 bundles, insulated, unshielded (x96) going to 6 DHEs = 3.6” Mix different sizes of power cables to achieve smallest cable bundle diameter/run & dissipated heat load/run to DHEs Use smaller wires with short cable lengths (& less volt. drop) in the DHE to get power to backplane and transition boards

8. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20078 Acopian Power Supply Selection

9. Todd Moore for the DES CollaborationPSTalkJune 13 th, 20079 Size & Mounting Specs

10. Todd Moore for the DES CollaborationPSTalkJune 13 th, 200710 Standard Features Input Voltages of 110VAC or 220VAC, 50-400Hz, Single phase Ripple of 250uV RMS Regulation of +/-0.005% Remote Sensing Short circuit proof with automatic recovery (electronic current limiting) Outputs are floating

11. Todd Moore for the DES CollaborationPSTalkJune 13 th, 200711 Optional Features Over-voltage protection, internal SCR shorts outputs at supply with OVP condition fault Under/Over-voltage Alarm circuit with SPDT relay switch if power supply output deviates by: 1.0 volt or more: on 5 volt models 2.0 volts or more: on 6-48 volt models NO alarm for 3.3 volt models Power-Up/Down and fault sequencing is handled by: –Leverage engineering support at Acopian –Use solid state relays to control the AC input to each supply Crydon Series 1 SSR