JPS6130006A - Method of trimming resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is a resistor trimming method for adjusting a resistor to a desired resistance value, and is particularly applicable to a method in which a large number of minute resistors formed by printing etc. are scattered within a substrate. This invention relates to a method for trimming such a resistor.

Conventional configuration and its problems In recent years, with the development of electronic component mounting technology, the components themselves have become smaller. One of the mounting methods is Hypto IC (hereinafter referred to as HIC). The resistor used in HIC is manufactured by forming resistor electrodes and wiring patterns on a ceramic substrate, and then printing or vapor depositing the resistor.

However, due to variations in the compounding conditions and firing conditions of resistor materials, the accuracy of the low value is within ± of the design value.
This results in an error of about 10 to 205%. Therefore, final resistance value adjustment by resistor trimming is required. There are two types of resistance value adjustment: element trimming, which trims the resistance value itself to the standard value, and functional trimming, which trims the resistor to the standard value while measuring the circuit characteristics while the circuit is operating. .

First, regarding the conventional trimming method of a resistor, electrodes (8a) and (8b) attached to the ends of the resistor (1) are trimmed by a trimming device (not shown) in order to adjust the resistance value of the resistor (1) to a desired resistance value. This is the trimming groove made in 1). (4) is N, pole (
2a) A probe pressure-welded to (2b), (5) a resistance value measuring means for measuring the resistance value of the resistor (1), and (6) a means for comparing the resistance value of the resistor (1) with a desired resistance value. This is a comparison means for determining whether the resistance value of the resistor being trimmed exceeds the desired resistance value. Figure 2 is a partial view of the resistor and electrode parts in Figure 1, where (7a) is the position where the first trimming groove (3a) is to be made, and (7b) is the position where the second trimming groove (8b) is to be made. ). Note that (7a) and (7b) may be interchanged. First, as shown in FIG. 2(b), a minute distance Δl is formed on the resistor by a trimming device. This trimming groove blocks the current flowing through the resistor, increasing the resistance value of the resistor. Next, the resistance value after forming the trimming groove is measured by the resistance value measuring means (5), and the measured resistance value is measured by the comparing means (6).
The resistance value is compared with the desired resistance value, and if the desired resistance value is exceeded, the trimming is stopped. If the resistance value is less than the desired resistance value, trimming is further performed by a minute distance Δl to form a trimming groove. At this time, the trimming groove l becomes (number of trimming repetitions l, and if 1:>1
If it is 1, the formation of the first trimming groove is stopped, and the process moves to the second trimming groove position (7b), as shown in FIG.
As shown in d), the formation of the trimming groove of Δl is controlled to start from the end of the resistor, and the steps of trimming, measuring the resistance value, and comparing it with the desired resistance value are repeated, resulting in the result shown in Figure 2. It is trimmed as shown in (d). Through the above procedure, the trimming groove forming operation for setting the resistance value of the resistor (1) to a desired resistance value is executed.

However, with this traditional trimming method,
Finally, as shown in Figure 8(a), the maximum length 11 of the first trimming groove (8a) was too short, and the length of the second trimming groove (8b) had to be made longer on the resistor. If the desired resistance value is not achieved, or as shown in Figure 8(b),
The maximum length 11 of the first trimming groove (8a) is too long, and the second trimming groove (8b) is not formed at all. Power concentration tends to occur at points, which deteriorates the reliability of the resistor after trimming.Also, by forming a minute-distance trimming groove on the resistor → measuring the resistance value → comparing the measured resistance value with the desired resistance value. At present, the resistor is trimmed by comparing the trimming groove length with the maximum trimming groove length, so there is currently a problem that trimming cannot be performed at high speed.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a method for trimming a resistor that is highly reliable and can perform trimming at high speed without power concentration at the tip of the trimming groove.

Structure of the Invention The resistor trimming method of the present invention calculates the trimming distance to be applied to the resistor from the initial resistance value of the resistor to be trimmed, the desired resistance value obtained by trimming, and the dimensional force of the resistor. This method is characterized in that the resistor body is trimmed using the calculated trimming distance.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

Figure 4 shows the resistor trimming method of the present invention.
) is an external view when applied to W4, resistor width,
L is the resistor length. As shown in Figure 4, the trimming groove (8a) is placed at a position (L/4) from the end of the electrode (2a), and the trimming groove (8b) is placed at a position (L/4) from the end of the electrode (2a).
8a) Sarani (L/2), Tsumariden @ (2a)
(7) Electric power) is formed at the position of ((8L)/4) and is %N. In such a positional relationship, the lengths of the trimming grooves (8a) and (8b) are equal, and it is defined as l, and the resistance value of the resistor (10) before forming the trimming groove is the initial resistor R. If the resistance value after forming the trimming grooves (8a) and (8b) is R, the trimming distance l can be determined by the above equation 1 (1) or equation 2.

LZ=2. J7e (x + r) ・
・・・・・・・・・ (1)R.

However, W>L/2 /=W(1-'sin 'exp ("-< (1-town) ・--(2) π 8W
R0 where w<L/2 Next, a method for trimming the resistor of this embodiment will be explained using FIG. 5. First, determine the resistor width W1 and the resistor length, and then use the first or second equation based on the initial resistance R0 and the desired resistance value R.
Calculate the trimming distance l using the formula. Next, Figure 5 (
As shown in a), connect the first trimming groove (8a) to the resistor (
1) Trimming distance l without measuring the resistance value
Form only the length of.

Next, the second trimming groove (8b) is formed as shown in FIG. 5(b) without measuring the change in the resistance value of the resistor up to a length close to the trimming distance l. After that, Figure 5 (C
), trimming grooves are formed by minute distances Δl, but in this case, the resistance value of the resistor is measured, and the measured resistance value is used to form distance trimming grooves for the resistance value comparison means. Perform trimming to reach the desired resistance value.

According to this embodiment, the trimming distance is calculated from the shape and dimensions of the resistor, the initial resistance value, and the desired resistance value, and the resistance value of most of the first trimming groove and the second trimming groove is not measured. By forming a trimming groove in , and then increasing the second trimming groove by △l and performing trimming while measuring the resistance value,
Resistor elements can be trimmed quickly and with high precision.

FIG. 6 shows another embodiment. FIG. 6 shows an external view when eight trimming grooves are formed. The trimming grooves should be arranged in the positional relationship shown in Figure 6, that is, the length of the resistor should be 1:2.
: When formed at a position where the ratio is 2:1, the trimming length l can be determined by the following equation 8 or 4.

1 = ,, :1o1e(x 11'2"i) song/song (3) Ro However, W>i2, -, Lπ R f=W(1--; sln exp(,, (1-H,
) 'j -' (4) However, in the case of the W-pitch embodiment, as in the previous embodiment, the 8th resistor width W, resistor length L, initial resistance value R8, and desired resistance value R are Calculate the trimming distance 1iIII! using the formula or the fourth formula.Next, the first and second trimming grooves are cut without measuring the resistance value of the resistor.
A trimming groove is formed with a length of trimming distance l.

Next, the eighth trimming groove is formed up to the vicinity of the trimming distance l without measuring the change in resistance value of the resistor. After that, a trimming groove is formed by a minute distance Δl in length, and at this time, the resistance value of the resistor is measured, and the measured resistance value is compared with the resistance value comparison means (5).
It is determined whether the desired resistance value has been exceeded, and if the resistance value has not been exceeded, a trimming groove is further formed by a minute distance Δl, the resistance value is measured, and trimming is performed in the following steps to make the resistance value the desired resistance value.

In this embodiment, the trimming groove forming device is multiplied by the resistor length by an integer ratio, but this is a positional relationship for determining the trimming distance l, and the trimming groove forming device is used when actually trimming the resistor. The formation position is not limited to this positional relationship.

In addition, when forming a plurality of trimming grooves with substantially equal lengths that satisfy the calculated trimming distance, the resistor width W
You can know the difference (W-7) between and the trimming distance l,
In advance, W-
When the value of l is less than a certain threshold value, it is determined that a satisfactory resistor cannot be obtained with the plurality of trimming grooves, and it is possible to switch to another trimming method before starting unnecessary trimming. In addition, when trimming precision is not required, the final grain trimming groove can be formed without the need to measure the resistance value, and the trimming distance t determined by calculation can be used.
It is obvious that it is only necessary to trim the length of .

Effects of the Invention As is clear from the above explanation, the method for trimming a resistor of the present invention calculates the trimming distance from the shape and dimensions of the resistor, the initial resistance value, and the desired resistance value, and performs trimming based on this calculation. By trimming the resistor so that the lengths of the plurality of trimming grooves are approximately equal, the problem of power concentration at the tips of the trimming grooves due to uneven lengths of the trimming grooves is eliminated. It also has a high trim ratio (
The resistance value after trimming/initial resistance value) can be easily achieved, and furthermore, trimming can be applied to the resistor from the trimming groove of the first grain to the trimming groove of the last grain without measuring the resistance value, making it extremely A great effect can be obtained in that trimming can be performed at high speed.

[Brief explanation of the drawing]

Figure 1 is a conceptual diagram of resistor trimming, Figure 2 is an explanatory diagram of a conventional resistor trimming method, Figure 8 is an external view of a resistor subjected to the conventional resistor trimming method, and Figure 4 is an explanatory diagram of a conventional resistor trimming method. The figure is an external view of a resistor in which a trimming groove is formed according to the present invention, FIG. 5 is an explanatory view of the trimming process of FIG. It is.

Claims (2)

[Claims] 1. Calculate the trimming distance to be applied to the resistor from the initial resistance value of the resistor to be trimmed, the desired resistance value obtained by trimming, and the shape and dimensions of the resistor, and use this calculated trimming distance to trim the resistor to the resistor. How to trim your body. 2. 2. The method of trimming a resistor according to claim 1, wherein a plurality of trimming grooves having substantially equal lengths are formed using the calculated trimming distance.