Design summary Status of the development & production - test run with S3a and S3b prototype - performance tests To do list for production & development - ongoing production J. Schneider / / DEPFET workshop at Ringberg castle DEPFET power supply

Design summary: DEPFET power supply DEPFET Power supply for lab measurements & TB runs ! 20 individual supply channel high voltage supply module voltage and current measurement remote control via USB storage of all supply settings output card defines purpose two prototypes are available - one for the S3a system - one for the S3b system (CERN - DEPFET TB at SPS )

Channel configurations: DEPFET power supply 0 to mA source/sink 0 to mA source/sink +/ mA source/sink 0 to mA source 0 to mA sink 0 to mA sink 0 to mA source 0 to mA source channel configuration is independent of the others even on the same module channels on same card share same GND channels on different cards are insulated from each other total output current of one quad supply module is limited to 300mA / 800mA OpAmp output stage (low current) Darlington output stage (high current)

Channel configurations (principle): DEPFET power supply OpAmp output stage (low current) Darlington output stage (high current) +-+- UoutDAC +-+- Uout DAC

Noise Distribution: mean = 12,17 ;  = 0,5 Common Mode:  = 16,3 DEPFET power supply Test run with S3a-System: (Contribution from Simone Esch, Bonn)

Noise Distribution: mean = ~14,5 Common Mode:  = ~16,8 DEPFET power supply Test run with S3b-System: (Contribution from Sergey Furletov, Bonn)

Resistive load response test: Channel config: OpAmp output Channel config: Darlington output - linear behavior till the OpAmp output protection clamps the voltage -> no regulation instability DEPFET power supply [mA][A] [V] - linear behavior - slope due to the resistive component of the conducting traces, connectors and cables to the measurement equipment -> no regulation instability

Capacitive load response test: -There is a need to do this test to see if regulation is stable -> we expect several capacitive loads on the hybrids -> The test with the DEPFET hybrids showed that the regulation is stable! but we do not know so far what is the safety margin DEPFET power supply

Load transient response for darlington output (high current) : 35mA transient (positive) 35mA transient (negative) -> no regulation instability -> no regulation instability

DEPFET power supply Noise measurement for darlington output (high current) : Conditions: 50 Ohm load 50 cm coaxial cable frequency band 160Hz – 58 -3dB Result: -> max. 1,3mV RMS noise measured over hole frequency band

time scale Status of the development & production progress: DEPFET power supply Development steps and work packages: available prototype for S3a-System (CURO2/Switcher2) linearity / dynamic range / control deviation load tests (resistive, capacitive and dynamic) firmware debugging for the USB microcontroller performance tests S3a-prototype: stable operation with module adapting to the S3b-system - redesign hardware S3b-prototype: stable operation with module writing the application software S3b-prototype: final tests S3b series production finally 10 power supplies available for TB & lab measurements Sep now Summer 2009

To do list for production & development : µC firmware needs still some extensions HV module is tested but not fully debugged capacitive load test -> more details some development in the control software for TestBeam issues series production of nine further supplies is ongoing -> backplanes -> quad cards -> HV modules -> output cards -> final assembly DEPFET power supply Hardware available: (for nine further P.S.) - cases - controller cards

DEPFET power supply... Questions so far? We are in time... for TB 2009 …

many thanks … …

Block diagram of the multi channel power supply: DEPFET power supply Single channel supply module Digital isolators USB Interface & Microcontroller Relay card D-Sub connector to DEPFET module Display & switches HV module Digital control bus, 24 V supply Analog voltage lines 5 quad supply modules + 1 HV module – 21 supply voltages – each module has a floating ground Controller – non volatile storage of voltage settings – USB interface (local control optional) Relay card – controlled switching of the voltage outputs Multi channel power supply in 15” case backplane Quad channel supply module Digital isolators Quad channel supply module Digital isolators Quad channel supply module Digital isolators Quad channel supply module Digital isolators Quad channel supply module Digital isolators

Quad supply module: DEPFET power supply four independent programmable output voltages with common floating ground voltage range: -25V … +25V output current : –+/- 15 mA (OPA output) –max. 300 mA (power transistor, config. current limit & pol.) voltage & current read back EEPROM stores/restores voltage settings optional front panel for local control Front panel isolated power supply & filter Bus connector EEPROM DA C current sense DA C current sense. DA C current sense DAC programmable voltage source ADC current sense voltage sense output voltages 24 V Quad supply module card SPI