loop structure

Abstract

The present invention provides a circuit structure that allows for easy and inexpensive control of current and other parameters through adjustment of resistance values, improves the reliability of current and other parameters control through resistance value adjustment, and facilitates easy modification of current and other parameters control through readjustment of resistance values. [Solution] The circuit structure 1 comprises a resistance section 2 including resistors 10a to 10d, and a short-circuit structure 6 that can switch between having a short circuit in a portion of each of the resistors 10a to 10d, i.e., having a short circuit in resistor 10a, resistor 10b, resistor 10c, and resistor 10d. By changing the state of having a short circuit in the short-circuit structure 6, the combined resistance value R1, which is a combined resistance value including the resistance value of the resistance section 2 and the resistance value of the reference resistance section 4, is adjusted.

Description

[Technical Field]

[0001] This disclosure relates to a circuit structure for further controlling at least one of current and voltage through adjustment of resistance values. [Background technology]

[0002] As a shared receiving amplifier having an operating current control element, the one described in Japanese Patent Publication No. 54-105449 (Patent Document 1) is known. The operating current control element in this shared receiver amplifier is a variable resistor. A typical example of a variable resistor is a potentiometer. A potentiometer has a body and a rotating part that rotates relative to the body. The person adjusting the resistance value for current control rotates the rotating part with a screwdriver or similar tool, and by adjusting the amount of rotation of the rotating part, they adjust the resistance value of the variable resistor and control the operating current of the amplification element. Furthermore, an optical transmitter having a variable resistor for controlling the output optical power of a light-emitting element is known, as described in Japanese Patent Publication No. 62-189771 (Patent Document 2). This optical transmitter is provided with a light-emitting element and a second transistor connected in series with the first transistor, and the base bias voltage of the second transistor is controlled by a variable resistor. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 54-105449 [Patent Document 2] Japanese Patent Application Publication No. 62-189771 [Overview of the project] [Problems that the invention aims to solve]

[0004] A potentiometer has a rotational life, which is the lifespan of the rotating part. A longer rotational life increases the cost of the potentiometer itself, and if a shorter rotational life is used to reduce costs, it may become difficult to adjust the resistance value, leading to replacement and increased hassle. For example, potentiometers with a long rotational life are expensive. On the other hand, potentiometers with a short rotational life are cheaper, but the adjuster may have difficulty adjusting them, consuming their rotational life and requiring replacement of the potentiometer or other components. Furthermore, the potentiometer itself is a component that can potentially fail, and if a failure occurs, it becomes impossible to adjust the resistance value. Furthermore, replacing a potentiometer is a time-consuming process that requires careful consideration of other components, such as removing the old potentiometer while desoldering it and then soldering a new one to the circuit board.

[0005] Therefore, the first main objective of this disclosure is to provide a circuit structure that allows for easy and inexpensive control of current and other parameters through adjustment of resistance values. Furthermore, a second main objective of this disclosure is to provide a circuit structure in which the reliability of current control, etc., is improved through the adjustment of resistance values. Furthermore, a third main objective of this disclosure is to provide a circuit structure that allows for easy modification of control, such as current, through readjustment of resistance values. [Means for solving the problem]

[0006] This specification discloses a circuit structure. This circuit structure may include a resistive section containing one or more resistors. The circuit structure may also include a short-circuiting section in which the presence or absence of a short circuit in a portion of each resistor can be switched. By changing the mode of presence or absence of the short-circuiting section, the combined resistance value, which is the combined resistance value including the resistance values ​​of the resistive sections, may be adjusted. [Effects of the Invention]

[0007] The first main effect of this disclosure is to provide a circuit structure that allows for easy and inexpensive control of current and other parameters through adjustment of resistance values. Furthermore, a second main effect of this disclosure is the provision of a circuit structure in which the reliability of current control, etc., is improved through the adjustment of resistance values. Furthermore, a third main effect of this disclosure is the provision of a circuit structure that allows for easy modification of control, such as current, through readjustment of resistance values. [Brief explanation of the drawing]

[0008] [Figure 1] This is a block diagram of a circuit including the circuit of the circuit structure related to this disclosure. [Figure 2] This is a surface view of the substrate including the circuit structure shown in Figure 1. [Modes for carrying out the invention]

[0009] The embodiments and modifications thereof relating to this disclosure will be described below with reference to the drawings as appropriate. This disclosure is not limited to such forms or variations.

[0010] Figure 1 is a block diagram of the circuit including the circuit of the circuit structure 1 according to this disclosure. Figure 2 is a surface view of the substrate B including the circuit structure 1. Circuit structure 1 controls the voltage to the voltage-controlled object. In this case, the voltage-controlled object is the current control terminal 92 of the MMIC 90 mounted on the CATV shared reception amplifier (CATV booster). In CATV boosters, multiple amplifiers are generally provided to obtain quality TV signals in the CATV band, and an MMIC90, a type of high-power amplifier with low distortion, is implemented as the final stage amplifier. "MMIC" stands for Monolithic Microwave Integrated Circuit. The MMIC90 is a semiconductor IC for amplifying TV signals. The MMIC90 has a current control terminal 92. The voltage V applied to the internal operating voltage terminal 94 is applied to the current control terminal 92. adj Accordingly, the current I flowing through the MMIC90 dd The voltage changes. The voltage at the internal operating voltage terminal 94 is the internal operating voltage V ddIt is as follows. The circuit structure 1 controls the voltage V of the current control terminal 92 with respect to the internal operating voltage terminal 94 in the MMIC 90 adj by adjusting the resistance value. In FIG. 1, the current control terminal 92 is indicated as "Adj". The circuit in FIG. 1 is a part of the circuit related to the amplifier at the final stage of the CATV booster.

[0011] In FIG. 2, only the elements related to the control of the current I of the MMIC 90, such as the circuit structure 1, the MMIC 90, and the wiring adjacent thereto, are shown, and most of the elements in the final stage amplifier are omitted. The shaded portion on the substrate B in FIG. 2 is a conductive conductor portion. dd Generally, since the characteristics related to the current I of the MMIC 90 are different for each individual, in the manufacture of the CATV booster, etc., for each individual, the voltage V applied to the current control terminal 92 is controlled, so that the current I of the CATV booster is controlled, and thus the desired characteristics related to the current I dd are obtained. Here, the characteristics are that the distortion rate is below a predetermined level and the heat generation amount is below a predetermined level. adj Incidentally, the voltage control target may be a terminal other than the current control terminal 92 with respect to the internal operating voltage terminal 94 of the MMIC 90, or an element or a part thereof such as another semiconductor in the CATV booster, or an element or a part thereof in a device other than the CATV booster. Examples of devices other than the CATV booster include an amplifier for UHF common reception (UHF booster) related to UHF band TV signals and an amplifier for BS·CS common reception (BS·CS booster) related to BS·CS band TV signals. Also, instead of controlling the voltage with respect to the internal operating voltage terminal 94 through the adjustment of the resistance value, the circuit structure 1 may control the voltage with respect to other terminals, etc. The characteristics related to the current I dd controlled in the CATV booster may be only one of the distortion rate or the heat generation amount, or may be other things. dd dd

[0012] The circuit structure 1 includes a resistor 2, a reference resistor 4, and a short-circuit structure 6.

[0013] The resistor section 2 includes several (four in this case) resistors 10a to 10d. These resistors 10a to 10d are, in order from furthest from the current control terminal 92 of the MMIC 90, resistor 10a, resistor 10b, resistor 10c, and resistor 10d. Resistors 10a to 10d are connected in series. The resistance value of resistor 10a is R a Therefore, the resistance value of resistor 10b is R b Therefore, the resistance value of resistor 10c is R c Therefore, the resistance value of resistor 10d is R d It is said that... Furthermore, there may be one resistor, three or fewer resistors, or five or more resistors. Also, some or all of the resistors may be connected in parallel.

[0014] The reference resistance section 4 includes one or more resistors. The resistance value of the resistors in the reference resistance section 4 (or the combined resistance value if it includes multiple resistors), i.e., the reference resistance value, is R0. Resistor 2 and reference resistor 4 are connected in series. The combined resistance of resistor 2 and reference resistor 4 is given as the combined resistance R1. Furthermore, the reference resistor section 4 may be omitted. Also, some or all of the resistor section 2 and the reference resistor section 4 may be connected in parallel. Moreover, if the reference resistor section 4 is omitted and there is only one resistor in the resistor section 2, the combined resistance value R1 is the same as the resistance value of the resistor in the resistor section 2.

[0015] The short-circuit structure 6 includes multiple (in this case, four) solder bridge sections 20a to 20d. These solder bridge sections 20a to 20d are, in order from furthest from the current control terminal 92 of the MMIC 90, solder bridge section 20a, solder bridge section 20b, solder bridge section 20c, and solder bridge section 20d. Each solder bridge section 20a to 20d has a first terminal and a second terminal. Before soldering, the first and second terminals face each other, separated by an insulating portion of the substrate B. Furthermore, the first and second terminals are short-circuited when soldered together with solder SD. The outer edge of the first terminal opposite to the second terminal is arc-shaped. The outer edge of the second terminal opposite to the first terminal is also arc-shaped. The combined shape of the first and second terminals is circular or elliptical. Thus, because the first and second terminals of each solder bridge section 20a to 20d have an arc-shaped form, the heated solder SD flows more easily to the required location, making it easier to apply the solder SD compared to the case where the first and second terminals are rectangular. Furthermore, the size of each solder bridge portion 20a to 20d, that is, the combined size of the first and second terminals, is preferably 2 mm from the viewpoint of obtaining ease of soldering without compromising compactness. Moreover, the distance between the first and second terminals, that is, the gap between the solder bridge portions 20a to 20d, is preferably 0.6 mm from the viewpoint of ease of soldering and ease of removing solder SD. Note that at least one of the outer edges of the first terminal and the second terminal does not have to include an arc. The combined shape of the first and second terminals does not have to be circular or elliptical. At least one of the size and gap of at least one of the solder bridge portions 20a to 20d may be different from those described above. Solder bridge 20a is connected in parallel with resistor 10a. Solder bridge 20b is connected in parallel with resistor 10b. Solder bridge 20c is connected in parallel with resistor 10c. Solder bridge 20d is connected in parallel with resistor 10d. When the solder bridge 20a is short-circuited, current flows through the conductive solder bridge 20a, which has a resistance significantly lower than that of the resistor 10a, rendering the resistor 10a ineffective. Similarly, when the solder bridge 20b is short-circuited, the resistor 10b is ineffective. Furthermore, when the solder bridge 20c is short-circuited, the resistor 10c is ineffective. In addition, when the solder bridge 20d is short-circuited, the resistor 10d is ineffective. The solder bridge section 20a switches between shorting resistor 10a and not shorting resistor 10a depending on whether soldering is performed. The solder bridge section 20b switches between shorting resistor 10b and not shorting resistor 10b depending on whether soldering is performed. The solder bridge section 20c switches between shorting resistor 10c and not shorting resistor 10c depending on whether soldering is performed. The solder bridge section 20d switches between shorting resistor 10d and not shorting resistor 10d depending on whether soldering is performed. The solder bridge sections 20a to 20d do not contain any components. Furthermore, the arrangement of the solder bridge sections 20a to 20d is not limited to those described above; for example, a solder bridge section in parallel with resistors 10a and 10b may be provided. Also, the short-circuit structure 6 is not limited to the solder bridge sections 20a to 20d; for example, it may be a single DIP switch containing multiple switch sections, multiple DIP switches containing one or more switch sections, a jumper wire, a 0Ω resistor, or a combination thereof.

[0016] Next, an example of the operation of circuit structure 1 will be explained. The person adjusting the resistance value of circuit structure 1 adjusts the combined resistance value R1 depending on whether or not solder SD is applied in the solder bridge sections 20a to 20d.

[0017] In the case where solder SD is not applied to all of the solder bridge sections 20a to 20d, the combined resistance value R1 is "R1 = R a +R b +R c +R d It becomes "+R0".

[0018] In the case where solder SD is applied only to the solder bridge portion 20a, the combined resistance value R1 is "R1 = R b +R c +R d It becomes "+R0". In the case where solder SD is applied only to the solder bridge portion 20b, the combined resistance value R1 is "R1 = R a +R c +R d It becomes "+R0". In the case where solder SD is applied only to the solder bridge portion 20c, the combined resistance value R1 is "R1 = R a +R b +R d It becomes "+R0". In the case where solder SD is applied only to the solder bridge portion 20d, the combined resistance value R1 is "R1 = R a +R b +R c It becomes "+R0".

[0019] In the case where solder SD is applied only to the solder bridge portions 20a and 20b, the combined resistance value R1 is "R1 = R c +R d It becomes "+R0". In the case where solder SD is applied only to the solder bridge portions 20a and 20c, the combined resistance value R1 is "R1 = R b +R d It becomes "+R0". In the case where solder SD is applied only to the solder bridge portions 20a and 20d, the combined resistance value R1 is "R1 = R b +R c It becomes "+R0". In the case where solder SD is applied only to the solder bridge portions 20b and 20c, the combined resistance value R1 is "R1 = R a +R d It becomes "+R0". In the case where solder SD is applied only to the solder bridge portions 20b and 20d, the combined resistance value R1 is "R1 = R a +R c It becomes "+R0". In the case where solder SD is applied only to the solder bridge portions 20c and 20d, the combined resistance value R1 is "R1 = R a +R b It becomes "+R0".

[0020] In the case where solder SD is not applied only to the solder bridge portion 20a, the combined resistance value R1 is "R1 = R a It becomes "+R0". In the case where solder SD is not applied only to the solder bridge portion 20b, the combined resistance value R1 is "R1 = R b It becomes "+R0". In the case where solder SD is not applied only to the solder bridge portion 20c, the combined resistance value R1 is "R1 = R c It becomes "+R0". In the case where solder SD is not applied only to the solder bridge portion 20d, the combined resistance value R1 is "R1 = R d It becomes "+R0".

[0021] In the case where solder SD is applied to all of the solder bridge sections 20a to 20d, the combined resistance value R1 will be "R1 = R0".

[0022] Thus, the combined resistance value R1 can be adjusted in various ways. When the combined resistance R1 changes, the voltage V across the current control terminal 92 of the MMIC90 changes. adj However, the internal operating voltage V dd It changes based on [a certain value]. Voltage V to current control terminal 92 adj When this changes, the current I of the MMIC90 dd It changes. Therefore, the current I of MMIC90 dd However, this is controlled by the presence or absence of solder SD in the solder bridge sections 20a to 20d.

[0023] For example, R c R g It is said to be about twice as much as R b R c It is said to be about twice as much as R a R b R is said to be about twice as much. a ~R d If the resistance values ​​are discrete, the combined resistance value R1 will be adjusted to different resistance values ​​depending on the presence or absence of solder SD in the solder bridge sections 20a to 20d.

[0024] Furthermore, the combined resistance value R1, and consequently the applied voltage V at the current control terminal 92, are also affected. adj , MMIC90 current I ddThe resetting can be easily controlled by at least one of the following: the appropriate application of additional solder SD to the solder bridge portions 20a to 20d, and the removal of solder SD from the solder bridge portions 20a to 20d by desoldering or other means.

[0025] The circuit structure 1 described above comprises a resistor section 2 containing multiple resistors 10a to 10d, and a short-circuit structure 6 that can switch between having a short circuit in a portion of each of the resistors 10a to 10d, i.e., having a short circuit in resistor 10a, resistor 10b, resistor 10c, and resistor 10d. By changing the mode of having a short circuit in the short-circuit structure 6, the combined resistance value R1, which is the combined resistance value including the resistor section 2 (and the reference resistor section 4), is adjusted. Therefore, the circuit structure 1 adjusts the resistance value of the resistor 2, and consequently the applied voltage V at the current control terminal 92. adj , MMIC90 current I dd Control can be performed simply and inexpensively without using components such as potentiometers with rotating parts. Furthermore, when adjusting the resistance value using circuit structure 1, there is no need to consider the failure and lifespan of components such as potentiometers with rotating parts, and the adjustment of the resistance value of resistor 2, and consequently the applied voltage V of current control terminal 92, can be controlled. adj The control is performed with greater reliability. Furthermore, the resistance value of resistor 2 is readjusted, and consequently the applied voltage V of the current control terminal 92 is also adjusted. adj , MMIC90 current I dd The control can be easily modified by changing the short circuit configuration, without requiring the removal of components such as potentiometers with rotating parts, or the installation of new components and adjustment of rotating parts.

[0026] Furthermore, the resistor 2 controls the current I of the MMIC 90, which is a type of amplification element. dd It is connected to the current control terminal 92, which is a terminal that controls the voltage V applied to the current control terminal 92 by adjusting the combined resistance value R1. adj The current I of the MMIC90 is controlled. dd This is controlled. Therefore, the current I of the amplifying element ddHowever, it is controlled in a way that is more reliable, simpler, cheaper, and easier to reset. In particular, regarding reliability, circuit structure 1 does not have a rotational life like a potentiometer, and by taking appropriate considerations such as derating, the resistance value does not change semi-permanently, thus achieving high reliability. Furthermore, the MMIC90 is included in the CATV booster. Therefore, the operator can easily and inexpensively adjust the CATV booster to a state where its amplification performance is fully realized. Furthermore, if an amplifying element like the MMIC90 is included in the UHF booster, the person adjusting the UHF booster can easily and inexpensively adjust it to a state where its amplification performance is fully realized. Similarly, if an amplifying element like the MMIC90 is included in the BS / CS booster, the person adjusting the BS / CS booster can easily and inexpensively adjust it to a state where its amplification performance is fully realized. Moreover, even if the semiconductor whose current is controlled by the circuit structure 1 is the MMIC90, which is an amplifying element that amplifies TV signals, and has a wider amplification bandwidth than audio amplifiers and data communication amplifiers, requiring adjustment of variations with higher precision, the circuit structure 1 can adequately control the current of the MMIC90. [Examples]

[0027] More specific embodiments based on the embodiments of the present disclosure described above will be explained below. Furthermore, this disclosure is not limited to the embodiments described below. Depending on how this disclosure is interpreted, an embodiment may become a comparative example that does not conform to the embodiments of this disclosure, or a comparative example may become an embodiment.

[0028] In this embodiment, the internal operating voltage V dd ga V dd When = 10(V), the voltage to the current control terminal 92 is V adj By adjusting the combined resistance value R1, the current I of the MMIC90 can be controlled. ddThis controls the current within a predetermined range. The predetermined range is set to 500mA to 550mA, from the viewpoint of ensuring a certain level of distortion performance and suppressing heat generation to keep the amount of heat generated within a predetermined level in the CATV booster using the MMIC90 of this embodiment.

[0029] The person adjusting the combined resistance value R1 should, in advance, test it, and V dd Under the condition =10(V), the current I in the MMIC90 as a sample dd Then, we measure the relationship with the combined resistance value R1. In this test, to obtain various resistance values ​​for the combined resistance R1, a test variable resistor is placed in place of resistors 10a to 10d and the reference resistance section 4. Table 1 shows the current I measured in the test. dd The relationship between this and the equivalent resistance value R1 is shown. Note that in Table 1, the measured voltage V applied to the current control terminal 92 is shown. adj However, it is also listed.

[0030] [Table 1]

[0031] Table 1 shows that even in MMIC90s other than the sample, the current I of the MMIC90 dd It is assumed that this can be sufficiently approximated by a linear function of the equivalent resistance R1 of circuit structure 1. The linear function in question can be expressed by the following equation (1), where a is the slope and b is the intercept. I dd = a × R1 + b (1)

[0032] For equation (1), in Table 1, (R1,I dd Two sets of measured values, here (R1,I dd Using )=(13,583) and (20,485), a and b are determined. In these two sets of measured values, the unit of R1 is kΩ, and I dd The unit is mA. The unit of R1 is kΩ, I dd If the unit is mA, then equation (1) becomes equation (2). I dd (mA)= -14×R1(kΩ)+765 (2)

[0033] From equation (2), for the current I of MMIC90 dd to be within the range of 500 mA or more and 550 mA or less, it can be seen that the range of the combined resistance value R1 is preferably about 15.4 kΩ or more and 18.9 kΩ or less. In the following Table 2, for the current I in equation (2) dd when it becomes representative current values within the range of 500 mA or more and 550 mA or less, the respective resistance values (kΩ) of the combined resistance value R1 are shown. From this Table 2, it can also be seen that the range of the combined resistance value R1 is preferably about 15.4 kΩ or more and 18.9 kΩ or less.

[0034]

Table 2

[0035] Therefore, for each of the resistance values (kΩ) of the resistors 10a to 10d and the reference resistance section 4, for example, the adjuster sets a R a = 3.6, sets b R b = 1.8, sets c R c = 0.91, sets d R d = 0.47, and sets R0 = 12.0. These resistance values are all standard, and the resistors 10a to 10d can be used at low cost.

[0036] If the resistance values of the resistors 10a to 10d are set in this way, for the range of about 15.4 kΩ or more and 18.9 kΩ or less for the combined resistance value R1 to make the current I of MMIC90 dd within the range of 500 mA or more and 550 mA or less, a range of the combined resistance value R1 that includes a margin above and below respectively can be obtained. That is, if solder SD is placed on all of the solder bridge portions 20a to 20d of the short structure portion 6 by the adjuster and all of the solder bridge portions 20a to 20d are shorted, the combined resistance value R1 becomes the lower limit of 12.0 kΩ. Also, if solder SD is not placed on all of the solder bridge portions 20a to 20d and all of the solder bridge portions 20a to 20d are not shorted, the combined resistance value R1 becomes the upper limit of 3.6 kΩ + 1.8 kΩ + 0.91 kΩ + 0.47 kΩ + 12.0 kΩ = 18.78 kΩ. And if only a part of the solder bridge portions 20a to 20d is shorted, the combined resistance value R1 becomes a resistance value between the above lower limit and upper limit.

[0037] In the manufacture of a CATV booster or the like, the adjuster measures, with an ammeter, the current I of the MMIC90 at the internal operating voltage V in a state where solder SD is not placed on all of the solder bridge portions 20a to 20d. dd at dd the MMIC90. Then, the adjuster determines the presence or absence of solder SD in the solder bridge portions 20a to 20d according to the measured current I and performs soldering as appropriate. dd and performs soldering as appropriate. Table 3 below shows the current I before adjustment and the current I after adjustment for each mode of the presence or absence of solder SD. “NC” in Table 3 indicates that solder SD has not been applied, that is, there is no solder SD. Also, “Short” in Table 3 indicates that solder SD has been applied and shorted, that is, there is solder SD. dd and the current I after adjustment dd are shown.

[0038]

Table 3

[0039] For example, if the measured current I dd is within the range of 530 mA or more and 550 mA or less, no soldering is performed and the state where solder SD is not placed on all of the solder bridge portions 20a to 20d is maintained. Also, if the measured current I ddIf the current is within the range of 510mA or more and less than 530mA, the solder bridge section 20b is shorted by soldering, the resistor 10b is disabled, the combined resistance value R1 is slightly reduced, and the voltage V applied to the current control terminal 92 is reduced. adj By slightly lowering the current I dd The regulator should increase the current I slightly. dd Increase the current so that it is within the range of 530mA to 550mA.

[0040] Furthermore, the adjuster measured the current I dd If the current is within the range of 490mA or more and less than 510mA, the solder bridge sections 20b, 20c, and 20d are short-circuited by soldering, and the resistors 10b, 10c, and 10d are disabled, further reducing the combined resistance value R1, and the voltage V applied to the current control terminal 92 is reduced. adj Further reduce the current I dd To further increase it. Furthermore, the adjuster measured the current I dd If the current is within the range of 475mA or more and less than 490mA, the solder bridges 20a and 20d are short-circuited by soldering, the resistors 10a and 10d are disabled, the combined resistance R1 is further reduced, and the voltage V applied to the current control terminal 92 is reduced. adj Further reduce the current I dd To further increase it.

[0041] In addition, the adjuster measured the current I dd If the current is within the range of 460mA or more and less than 475mA, the solder bridge sections 20a, 20c, and 20d are short-circuited by soldering, and the resistors 10a, 10c, and 10d are disabled, further reducing the combined resistance value R1, and the voltage V applied to the current control terminal 92 is reduced. adj Further reduce the current I dd To further increase it. Furthermore, the adjuster will measure the current I dd If the current is within the range of 445mA or more and less than 460mA, the solder bridge sections 20a, 20b, and 20d are short-circuited by soldering, and the resistors 10a, 10b, and 10d are disabled, further reducing the combined resistance value R1, and the voltage V applied to the current control terminal 92 is reduced.adj Further reduce the current I dd To further increase it. Furthermore, the adjuster measured the current I dd If the current is less than 445mA, the solder bridge sections 20a to 20d are shorted by soldering, the resistors 10a to 10d are disabled, the combined resistance R1 is further reduced, and the voltage V applied to the current control terminal 92 is reduced. adj Further reduce the current I dd To further increase it.

[0042] If the adjuster applies solder SD to at least one of the solder bridge sections 20a to 20d, the current I of the MMIC 90 after soldering will be... dd Measure and confirm that it is within the desired range. In the unlikely event that current I dd If it falls outside the desired range, the adjuster readjusts the combined resistance R1 by simply adding more solder or removing existing solder, thereby adjusting the current I of the MMIC90. dd You can control the resetting process. Furthermore, the measured current I dd In the region where the current is less than 445mA, the area may be further divided into regions where the presence or absence of soldering in the solder bridge sections 20a to 20d differs from each other. Also, the measured current I described above dd The relationship between the range and the presence or absence of soldering in the solder bridge sections 20a to 20d is just one example; the actual measured current I for each MMIC 90 will vary. dd Variation, amount of soldering work, current I dd The level of performance related to this, the error between the ideal resistance value obtained by approximating with a linear function and the actual resistance value, and the current I dd The settings can be varied depending on at least one of the requirements for ensuring a margin in the control of the system. Furthermore, to make adjustment by the operator easier, the measured current I dd A table may be created that describes the relationship between the range and the presence or absence of soldering in the solder bridge sections 20a to 20d.

[0043] In this way, by appropriately soldering the solder bridge portions 20a to 20d, which are the short-circuit structure 6 in the circuit structure 1, the current I of the MMIC 90 is controlled. dd The adjustment of the MMIC90, which is necessary for a CATV booster that is controlled and has sufficient performance at a low cost despite some variability, can be performed more appropriately without requiring the installation and adjustment of components such as volume controls. [Explanation of symbols]

[0044] 1 circuit structure 2 Resistor section 6 Short structural section 10a~10d resistor 90 MMIC (Mixing Microcontroller) 92 Current control terminal I dd (current of the amplifying element) R1 equivalent resistance value

Claims

1. A resistive section including one or more resistors, A shorting structure that can switch between having a short circuit or not for each of the aforementioned resistors, It is equipped with, By changing the state of whether or not a short circuit is present in the short structure, the combined resistance value, which is the combined resistance value including the resistance value of the resistance section, is adjusted. A circuit structure characterized by the following features.

2. The aforementioned resistors are multiple in number, The short-circuit structure can switch between having a short circuit in some of the resistors. The circuit structure according to feature 1.

3. The aforementioned short structure does not include any elements. The circuit structure according to feature 1.

4. The aforementioned short-circuit structure includes a solder bridge section that switches between having a short circuit or not depending on whether soldering is performed or not. The circuit structure according to feature 1.

5. The current of the semiconductor is controlled by adjusting the aforementioned combined resistance value. The circuit structure according to feature 1.

6. The semiconductor is an amplifying element that amplifies a TV signal. The circuit structure according to claim 5.

Images