JPS63215970A - Output voltage variation detector for high voltage generating circuit - Google Patents

Abstract

PURPOSE:To reduce the size of an instrument by connecting a plurality of voltage dividing resistors connected between the output end of a high voltage generating circuit and the ground in series and connecting a plurality of capacitors to the resistors in parallel under a prescribed condition. CONSTITUTION:An element group 9 is composed of voltage dividing resistors 9r1-9r9 and capacitors 9c1-9c10 all connected in series between the output end (a) of a high voltage generating circuit 1 and a ground side terminal. In the capacitors 9c1-9c10, when (i) takes integers 2, 3,...8, a capacitor 9ci is connected to the series connection of resistors 9ri-1 and 9ri in parallel and a capacitor 9ci+1 is connected to the series connection of resistors 9ri and 9ri+1 in parallel. The capacitors 9c1 and 9c10 are connected to the resistors 9r1 and 9r9, respectively, in parallel. Element groups 10-13 have the same structure as above. Thus, since the capacitors are alternately connected to the series connections of the two resistors in parallel, each capacitor can be arranged in the position of one side of a triangle with the other two sides arranged with the two resistors and the mounting space of elements are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a device for detecting output fluctuations of a high voltage generating circuit such as a Kotscroft circuit.

[Prior Art] In focused ion beam devices and the like, a high voltage generated by a high voltage generating circuit such as a Kotscroft circuit is applied to an electrostatic lens electrode. Therefore, if this high voltage fluctuates, the lens action of the electrostatic lens will fluctuate, causing blurring of the ion beam and deviation of the irradiation position. Therefore, in an apparatus that attempts to perform precise drawing using an ion beam, the high voltage generated by the high voltage generation circuit is detected, and this detection signal is sent to a feedback amplifier, so that the detection signal matches the reference value. The output voltage of the high voltage generating circuit is controlled to suppress its fluctuation.

Figure 3 shows such a conventional device, in which 1 is a high voltage generating circuit such as a Kotscroft circuit, 2.3.4
．． 5.6 is a group of voltage dividing elements, 7 is a feedback amplifier, and 8 is a reference signal generator. Voltage dividing element group 2 is the output terminal a of the high voltage generation circuit.
voltage dividing resistors 2r1, 2r2. ..., 2r9, and voltage dividing resistors 2r1, 2r2 . It consists of capacitors 2C1, 2G2, . . . , 2C9 connected in parallel to each of the capacitors 2C1, 2G2, .

Further, each voltage dividing resistor 2r1, 2r2,..., 2r9 has a common resistance value r, and each capacitor 2c1, 2c2,..., 2r9 has a common resistance value r.
..., 2c9 have a common 8 hanging C. Therefore,
The time constant at each voltage dividing resistor element stage is rc, and is equal at each stage. The voltage dividing element groups 3, 4, and 5°6 also have exactly the same configuration as the voltage dividing element group 2.

In such a configuration, as mentioned above, the distribution of time constants in each resistive element stage is equal, so if a high voltage is divided and extracted from between resistors 6r8 and 5r9, which is a voltage dividing point close to the ground side, , it is possible to extract a signal whose characteristics are not biased due to frequency and send it to the feedback amplifier 7.

By the way, each of the above-mentioned element groups is mounted by incorporating each resistor and capacitor into a printed circuit board.

FIG. 4 illustrates this implementation, and in FIG. 4, the same components as in FIG. 3 are given the same numbers.

[Problems to be Solved by the Invention] As can be seen from FIG. 4, in the conventional device, since a capacitor is connected in parallel to each resistor, the resistor (
For example, in order to prevent dielectric breakdown between 2r1> and the next stage resistor (2r2), the gap must be widened by the capacitor (for example 2C1) placed between them, and therefore,
One printed circuit board becomes larger. Since a large number of printed circuit boards are required to mount such a group of elements, the conventional output voltage fluctuation detection device for a high voltage generation circuit has to be large in size.

It is an object of the present invention to solve these conventional drawbacks and provide an output voltage detection device for a small high voltage generation circuit.

[Means for Solving the Problems] Therefore, the present invention provides voltage dividing resistors r1.1. r2. r
3. ..., ri-1, ri, ril.

..., rn and i are 2.3. ..., n-1, a capacitor ci connected in parallel to the series connection of the resistor ri-1 and the resistor ri, and a capacitor ci1 connected in parallel to the series connection of the resistor ri and the resistor ri1. Prepare,
It is characterized in that an output from a voltage dividing point close to the ground side is taken out in order to detect the output voltage of the high voltage generating circuit.

[Example] Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a diagram for showing one embodiment of the present invention.
In the figure, the same components as in FIG. 3 are given the same numbers. In FIG. 1, 9, 10, 11.
1'2.13 is an element group, and the element group 9 includes voltage dividing resistors 9rl, 9r2, 9r3, . .
・, 9r9 and capacitor 9G1, 9c2.9c3,
・, 9c10, i is 2.3. ..., 8, a capacitor 9ci is connected in parallel to the series connection part of the resistor 9ri-1 and the resistor 9ri, and the resistor 9ri
A capacitor 9ci1 is connected in parallel to the series connection portion of the resistor 9ril and the resistor 9ril. Also, a capacitor 9 is connected to the resistor 9rt.
C1 is connected in parallel, and a capacitor 9C10 is connected in parallel to the resistor 9r9. The resistors 9r1, 9r
2.9r3, . . . , 9r9 have a common resistance value r, and the capacitors 9c2.9c3, .
, 9c9 have a common capacitance value C/4, and capacitors 9c1, 9c10 both have a capacitance value C/2. Therefore, when considering the equivalent circuit of element group 9, the equivalent circuit is the same as the circuit configuration of element group 2. Also, 13r1
．． 13r2, 13r3. ..., 13r9 is a voltage dividing resistor,
13c1.13c2.13c3, . . . , 13clO are capacitors, and the element group 10.11.12.13 also has exactly the same configuration as the element group 9.

With this configuration, the output voltage detection function of the high voltage generation circuit is the same as that of the conventional device, but the resistors and capacitors forming the element group can be mounted as shown in FIG. In FIG. 2, the same components as in FIG. 1 are designated by the same reference numerals. That is,
As is clear from FIG. 2, since each capacitor is alternately connected in parallel with two resistors connected in series, both resistors are connected to the first . The capacitor can be placed at the third side of the triangle, which is the second side, and there is no need to increase the distance between the two resistors by the amount of the capacitor, unlike in the conventional case. Therefore, the space required for mounting each element can be reduced, and as a result, the output voltage fluctuation detection device of the high voltage generation circuit can be made smaller.

Note that the above-described embodiment is only one embodiment of the present invention, and the present invention can be modified and implemented.

For example, in the above-mentioned embodiment, the time constant of each resistor stage was made constant so that the extracted detection signal would not have any bias in characteristics due to frequency. The capacitance of the resistor or capacitor may be adjusted.

Further, the number of stages of voltage dividing resistors in the above-described embodiments can be changed depending on various cases, and the number of element groups can also be changed.

[Effects of the Invention] As is clear from the above description, according to the present invention, the space required for mounting a voltage dividing element group consisting of a resistor and a capacitor can be reduced, and thereby the output voltage fluctuation detection device of a high voltage generation circuit can be Can be made small.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram for explaining the present invention in detail, FIG. 3 is a diagram showing a conventional device, and FIG. 4 is a diagram of a conventional device. It is a figure for showing a defect. 1: High voltage generation circuit 7: Feedback amplifier 8: Reference signal generation source

Claims (1)

[Claims] Voltage dividing resistors r1, r2, r3, ..., ri- connected in series between the output end of the high voltage generation circuit and the ground.
1, ri, ri1,..., rn, and i to 2, 3,...
, n-1, a capacitor ci connected in parallel to the series connection portion of the resistor ri-1 and the resistor ri, and a resistor r
i and a capacitor ci1 connected in parallel to the series connection portion of the resistor ri1, and an output from a voltage dividing point near the ground side is taken out for detecting the output voltage of the high voltage generating circuit. Output voltage fluctuation detection device for high voltage generation circuit.