This page describes a project to develop an inexpensive programmable high-voltage supply system for PMTs.  This is currently generic R&D but may develop into a system used for i.e. Super-Kamiokande or the propose Long Baseline Neutrino Experiment (LBNE) at Homestake.

== Target Specifications ==

(from LBNE requirements document... take with a grain of salt!)

||Voltage Setting || 1500-2500V || 1V steps || Groups of 16 within 300V range ||
||Ripple || <100mV at PMT base || || ||
||Voltage Readback || || || ||
||Current Readback || || || ||
 
The proposed PMT for LBNE requires no more than 1800V, so a range of 1500V-1800V is surely adequate.
Current requirement is under discussion but likely ~ 100uA per channel.

A modularity of 16 channels with individually adjustable outputs is forseen.

== First Prototype ==

* [[PMT_HV_Test_Log]]
* [[PMT_HV_Test_Software]]
* [http://ohm.bu.edu/~hazen/LBNE/HV_Supply/ PCB Design]
 * [http://ohm.bu.edu/~hazen/LBNE/HV_Supply/Pico_Tester_ECO_sch.pdf Pico_Tester_ECO_sch.pdf]

This is a test board to characterize the Pico 12VV2 DC/DC converter.  It consists of a two-stage op-amp driver circuit to provide the necessary 0-12V @ 1A maximum input to the Pico, with a choice of feedback options.  Voltage may be set by a pot or external signal.  An SHV connector for the PMT cable and signal coupling capacitor are provided in case we want to connect an actual PMT.

== Candidate Components ==

* Pico Electronics [http://www.picoelectronics.com/dcdclow/pe66_67.htm VV series]
* Supertex [http://www.supertex.com/pdf/datasheets/LR8.pdf LR8]
* ST micro VB408 (discontinued).  See [http://www.changpuak.ch/electronics/VB408.html this circuit]
  This is a nice idea, but draws way too much standing current for use as-is.