High Voltage Supply - LUDLUM MODEL 19 Manual

Model 19 MICRO R METER
Ludlum Measurements, Inc.
Technical Manual
through analog switch logic circuit U15, U14, and U3.

High Voltage Supply

High voltage is developed by switching regulator U13 and T1. Voltage
multiplier CR3 thru CR7, and associated components, develop the detector
voltage. Voltage feedback is provided by R39 thru U17 to feed back pin 8 of
U13 for voltage regulation. Pin 1 of U17 is proportional to the high voltage,
and its output is also utilized to measure the high voltage. High voltage is
adjusted by varying the feedback current with R42.
Page 7-3
Section 7
February 2012