HV-Splitter for RENO Project S. Stepanyan, 김우영 경북대학교 Y.Kim Sejong University May-2008.

PMT-base circuit A-high Potential; back terminated for large signals by 50ohm and 4.7nF cap. to ground K-photocathode should be kept at ground potential to avoid discharges which might be occur between K and outer envelope of the detector. RG303C 50 ohm cable sealed in the PMT base with SHV connector. 0.1mA divider

Eight channel HV Splitter

HV Splitter Circuit HV PS outputs should be floating, such that crate ground is independent of the return for the HV channels. 100ns single cable for readout and supply of HV which minimizes the ground loops noise. Having termination at both PMT base and the HV splitter (100 ns cable) reduces the reflections to 1%.

HV Splitter Goals Expected PMT signals ~2mV which passing first through HV-splitter Decouple the signals coming out PMT s from the HV supplies. Terminate the PMT cable transmission line to minimize pulse reflections, Distribute HV among several PMT s per HV channel. Provide filtering of the HV to reduce noise comes from HV supplies.

CAEN-A Floating PS

CAEN ch/500mkA-HV-PS

EMCO-8SHV-connectors-2kV- 0.5mA-Output/24V/2A-Input

DC-HV-splitter-prototype

HV-Splitter with decouple-circuit

Differentiating effect of the HV blocking capacitance

50mV PS Noise on Summed PMT Signals-DC

DC to DC generator microcpip

Output Voltage dependence from DAC voltage

The HV(High Voltage) system configuration from microchips of DC to DC HV generators of EMCO or CAEN Model A864 provides a programmable and monitorable output voltage ranging from 0 to 2kV when supplied 12v input voltage, size 25mmmx100mmx13mm; one ch. manufacturer CAEN A3006 6channel 4-16V/6A/90W(per ch.) LV PS from CAEN A ch DAC(12bit resolution) +4V/10mA DAC(digital analog convertor)

EMCO+ CAEN with 4 additional wires to PMT base(2 input and 2 from DAC for programming control) length of wires should be same for all PMT dividers. A) model CA20P-5. DC to DC HV generator manufacturer of EMCO B) model CM1One ch.CA series Chassis mount kit manufacturer of EMCO. C) A ch 2-8V/9A/45W(per ch) manufacturer CAEN D) A ch DAC(12bit resolution) +4V/10mA DAC manufacturer CAEN.

AS a Day Bay proposal.. By using manufacturer Analog, Inc. Microcontroller ADuC845/ADuC847/ADuC848. DC to DC HV generator manufacturer of EMCO. Also we should think about LV PS and should develop software of the microcontroller

End Thank you for Attention

Front and back panels of HV Splitter