Abstract
The described system is developed in the framework of a deep-sea submerged Very Large Volume neutrino Telescope where photons are detected by a large number of Photo Multiplier Tubes. These PMTs are placed in optical modules (OM). A basic Cockcroft-Walton (CW) voltage multiplier circuit design is used to generate multiple voltages to drive the dynodes of the photomultiplier tube. To achieve a long lifetime and a high reliability the dissipation in the OM must be kept to the minimum. The design is also constrained by size restrictions, load current, voltage range, and the maximum allowable ripple in the output voltage. A surface mount PMT-base PCB prototype is designed and successfully tested. The system draws less than 1.5 mA of supply current at a voltage of 3.3 V with outputs up to -1400 Vdc cathode voltage, a factor 10 less than the commercially available state of the art.
Highlights
The described system is developed in the framework of a deep-sea submerged Very Large Volume neutrino Telescope where photons are detected by a large number of Photo Multiplier Tubes
A very interesting and efficient alternative is the Cockcroft Walton multiplier or the Villard cascade. In this case energy from an alternating source is transferred by pumping capacitors through rectifiers into buffer capacitors near the dynodes [4]
In single photon count mode, the electron current in the tube will be very low and the buffer capacitor holds only the charge to adjust the dividers on the right level
Summary
A very interesting and efficient alternative is the Cockcroft Walton multiplier or the Villard cascade (figure 3). In this case energy from an alternating source is transferred by pumping capacitors through rectifiers into buffer capacitors near the dynodes [4]. The PMT requires the highest current at the last dynode, next to the anode This is attached to the lowest stage of the CW chain (the lowest voltage), the point at which the chain can supply the highest current. At the higher stages of the CW chain (the highest voltage), where it is much harder for the CW multiplier to supply current, the PMT requires only a few electrons for each hit.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
