Browse Prior Art Database

High Voltage Power Supply Regulator

IP.com Disclosure Number: IPCOM000051441D
Original Publication Date: 1981-Jan-01
Included in the Prior Art Database: 2005-Feb-10
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Cato, RT: AUTHOR [+2]

Abstract

The drawing shows a digitally-controlled low-voltage circuit for controlling a high-voltage power supply, such as might be needed for a photomultiplier tube (PMT).

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 72% of the total text.

Page 1 of 2

High Voltage Power Supply Regulator

The drawing shows a digitally-controlled low-voltage circuit for controlling a high-voltage power supply, such as might be needed for a photomultiplier tube (PMT).

The circuit includes a digital-to-analog (D/A) converter 10, the effective resistance of which depends on the binary values of digital control signals applied to parallel solid-state switches in converter 10. The converter 10 serves as a variable resistor in a voltage divider consisting of converter 10 and fixed resistance 12. The voltage across converter 10 is applied at the base terminal of a transistor 14. The collector of transistor 14 is connected directly to the base terminal of a transistor 16 which, in combination with another transistor 18, forms a differential amplifier. A second input to the differential amplifier is a function of a collector voltage on transistor 20, the base terminal of which is connected in series with PMT 22.

Current flowing through the transistor 18 is applied to a light-emitting element in a first opto-isolator circuit 24. A phototransistor in circuit 24 provides a base bias voltage for a transistor 26. Transistor 26 is one element in the high-voltage supply circuit which includes fixed resistors 28 and 30, a second power transistor 32 and diodes 34 and 36. A negative high voltage source is connected to diode
36.

The control circuit also includes a second opto-isolator circuit 38 in which the light-emitting element is connected direc...