Abstract: The performance of a power supply module is to be improved. The occurrence of discharge in the power supply module is to be prevented, and the size of the power supply module is to be reduced. In a power supply module, substrates are provided being stacked in a planar view. A low voltage circuit and a high voltage circuit are formed on a first substrate such that a distance is kept for preventing surface discharge, and a low voltage circuit is formed on a second substrate. A distance between a component of a high voltage alternating current circuit on the high voltage circuit and a component of the low voltage circuit is three times a shortest distance, at which space discharge does not occurs, between a component that constitutes a high voltage direct current circuit on the high voltage circuit and a component that constitutes the low voltage circuit.

Abstract: A high-voltage module HVMD includes: an error amplifier configured to output a control signal based on a reference signal Vin and a feedback signal; a high voltage output circuit configured to output a high voltage Vout for supply based on the control signal; and a feedback circuit configured to output the feedback signal based on the high voltage Vout for supply. Here, the feedback circuit includes: a first partial circuit configured to receive an input of the high voltage Vout for supply and to output an intermediate signal, the first partial circuit including a resistance element; and a second partial circuit configured to receive an input of the intermediate signal and to output the feedback signal. The high-voltage module HVMD further includes a substrate SUB including: a high voltage substrate region where the high voltage output circuit and a part of the first partial circuit are mounted.

Abstract: In a mass spectrometer, due to impurities accumulated inside a frame, a withstand voltage may decrease, and electric discharge may occur in an ion source, thereby making it impossible to perform normal measurement. Since a result of abnormality measurement due to the electric discharge cannot be distinguished from measurement abnormality caused by clogging of a tube between a pretreatment unit and a needle, there is a problem in that time is required to identify abnormal portions, and a maintenance property is lowered. As a unit for solving the problem, a return current detection unit connected in series between the frame and an ion source power supply that applies a voltage to the needle and a return current detection unit connected in series between the frame and a counter electrode power supply that applies a voltage to a counter electrode are provided.