JP6681361B2 - Power supply - Google Patents

Description

  The present invention relates to a power supply device having a function of externally setting or varying an output voltage set value.

  Conventionally, as disclosed in Patent Document 1, a load that outputs a voltage instruction signal that indicates a required power supply voltage, and this voltage instruction signal are input to a trimmer terminal, and an output voltage set value is set based on the voltage instruction signal. There was a power supply system with a power supply that changed automatically. The load uses a resistor having a different value for each required power supply voltage when generating the voltage instruction signal. The output voltage setting circuit in the power supply device continuously changes the output voltage setting value with respect to the change of the voltage instruction signal (FIG. 3 of Patent Document 1).

  The power supply device of the power supply system of Patent Document 1 is a known device that has been conventionally used, and the power supply device 10 of this type is also used as shown in FIGS. 14 (a) to 14 (c).

  In FIG. 14A, a load 16 is connected between the output terminals 12 and 14 of the power supply device 10, and a fixed resistance element 20 having a predetermined resistance value is connected to the trimmer terminal 18 to connect the trimmer terminal 18 to the trimmer terminal 18. The structure which produces | generates a desired voltage instruction | indication signal is shown. When changing the voltage instruction signal, the fixed resistance element 20 is replaced with another fixed resistance element 20 having a different resistance value. Although the fixed resistance element 20 is provided separately from the load 16 in the configuration of FIG. 14A, it can be said that the configuration is substantially the same as the power supply system of Patent Document 1.

  In FIG. 14B, a constant voltage generating circuit 22 is provided between the output terminals 12 and 14 of the power supply device 10, a constant voltage generating circuit 22 generates a predetermined constant voltage (voltage instruction signal), and the trimmer terminal 18 receives the constant voltage. The configuration to be input is shown. The constant voltage generating circuit 22 is a series regulator or the like composed of a shunt regulator and a plurality of fixed resistors, and when changing the voltage instruction signal, the specific fixed resistor is replaced with another fixed resistor having a different resistance value. Do the work.

  In addition, in FIG. 14C, a variable power supply device 24 that outputs a constant voltage intended by a user with high accuracy is provided outside the power supply device 10, and a constant voltage (voltage instruction signal output by the variable power supply device 24 is provided. ) Is input to the trimmer terminal 18. The voltage instruction signal can be freely changed by the user.

The configurations of FIGS. 14A and 14B are suitable for a case where “the output voltage Vo is once set and then not changed”, and the power supply system can be configured simply and inexpensively. On the other hand, the configuration of FIG. 14C is suitable for the case where “the output voltage Vo is continuously varied during the operation of the power supply device”.

JP, 2003-164141, A

In the conventional power supply device 10, the output voltage setting circuit performs an operation of continuously changing the output voltage setting value with respect to the change of the voltage instruction signal, so that the output voltage Vo can be finely changed, and FIG. It is suitable for the usage such as "to continuously change the output voltage Vo while the power supply is operating" as shown in. However, it is not very suitable for the usage of “setting the output voltage Vo once and then changing it” as shown in FIGS. 14A and 14B.

  In the case of the configuration of FIG. 14A, the resistance value varies within the range of the tolerance due to the individual difference of the fixed resistance element 20, so that the target voltage instruction signal cannot be generated accurately. Similarly, in the case of the configuration of FIG. 14B, the constant voltage of the constant voltage generating circuit 22 varies due to individual differences in the shunt regulator and the plurality of fixed resistors, so that the target voltage instruction signal cannot be generated accurately. Therefore, when the power supply device 10 is used in the configuration of FIGS. 14A and 14B, the voltage instruction signal varies in a predetermined range, and thus there is a problem that the desired output voltage Vo cannot be obtained accurately.

  The present invention has been made in view of the above background art, and obtains a desired output voltage with high accuracy even when setting a output voltage by connecting a fixed resistance element or a constant voltage generation circuit to a trimmer terminal. It is an object of the present invention to provide a power supply device capable of

  The present invention is a trimmer terminal which is an external connection terminal for changing an output voltage setting value, and a means for determining the output voltage setting value according to a trimmer voltage generated at the trimmer terminal, wherein the trimmer voltage is And a set value determining unit that determines the output voltage set value based on a set value determination table that defines a relationship with the output voltage set value, and the set value determination table includes a predetermined trimmer voltage range. In the power supply device, a plurality of ranges divided into widths are defined, and the output voltage setting value that is different for each range is assigned.

  The trimmer voltage can be changed by externally connecting a fixed resistance element to the trimmer terminal, and for each output voltage setting value specified in the setting value determination table, the externally connectable fixed resistance element A nominal value and a tolerance are specified, and the width of each range specified in the set value determination table is such that the specified fixed resistance element is externally connected and its resistance value varies within the tolerance range. The trimmer voltage is set to be within the range.

  Alternatively, the trimmer voltage can be changed by externally inputting a constant voltage generated by a constant voltage generating circuit to the trimmer terminal, and the trimmer voltage can be changed for each of the output voltage set values stipulated in the set value determination table. The center value and allowable error of the constant voltage that can be input are specified, and the width of each range defined in the set value determination table is such that the specified constant voltage is externally input and the allowable error of the constant voltage is When there is variation within the range, the trimmer voltage is set to fall within the range.

When the trimmer voltage which is not included in the range defined in the setting value determination table is generated, the set value determining means, a configuration for determining the output voltage set value constant less safe value It is preferable. Alternatively, the set value determining means is further provided with a continuous function formula defining the relationship between the trimmer voltage and the output voltage set value, and the trimmer not included in the range specified in the set value determination table. When the voltage is generated, it is preferable that the setting value determining means determines the output voltage setting value based on the continuous function formula. In this case, the range of the output voltage set value determined based on the continuous function formula may be wholly or partially overlapped with the range of the output voltage set value determined based on the set value determination table. be able to. Further, the set value determination means is provided with a plurality of the set value determination tables, and is a table which is an external connection terminal for selecting one of the set value determination tables used when determining the output voltage set value. The selection terminal may be further provided.

  Alternatively, the set value determination means is further provided with a continuous function formula that defines the relationship between the trimmer voltage and the output voltage set value, and a mode for determining the output voltage set value based on the set value determination table. And a mode selection terminal which is an external connection terminal for selecting one of the modes for determining the output voltage setting value based on the continuous function formula. In this case, the set value determination means is provided with a plurality of the set value determination tables and is an external connection terminal for selecting one of the set value determination tables used when determining the output voltage set value. A table selection terminal may be further provided. The mode selection terminal may also be used as the table selection terminal, and the setting value determination table used when determining the output voltage setting value may be configured to be selected using the mode selection terminal.

  According to the power supply device of the present invention, the trimmer voltage generated at the trimmer terminal is detected and the output voltage setting value is determined based on the unique setting value determination table. Therefore, a fixed resistance element or a constant voltage generating circuit is provided at the trimmer terminal. Even when the output voltage is set by connecting with, the desired output voltage can be accurately obtained regardless of the accuracy of the connected element.

In addition, a mode for determining the output voltage set value based on the set value determination table and a mode for determining the output voltage based on the continuous function formula are provided so that the user can select which mode to use. Thus, it is possible to easily cope with both the usage of “setting the output voltage Vo once and not changing thereafter” and the usage of “ continuously varying the output voltage Vo while the power supply device is operating”.

It is a circuit diagram which shows 1st embodiment of the power supply device of this invention. 2A and 2B showing two set value decision tables registered in the set value decision means of FIG. 1 and designation of fixed resistance elements (nominal value and tolerance of resistance value) for each trimmer voltage range. is there. 3 is graphs (a) and (b) showing a relationship between a trimmer voltage and an output voltage set value, which is defined by two set value decision tables registered in the set value decision means of FIG. 1. It is a circuit diagram which shows 2nd embodiment of the power supply device of this invention. FIGS. 4A and 4B showing two set value determination tables registered in the set value determination means of FIG. 4 and designation of the constant voltage generation circuit for each trimmer voltage range (constant voltage center value and allowable error). ). 5 is graphs (a) and (b) showing the relationship between the trimmer voltage and the output voltage set value, which is defined by the two set value determination tables registered in the set value determination means of FIG. 4. It is a circuit diagram which shows 3rd embodiment of the power supply device of this invention. 8 is a graph showing a relationship between a trimmer voltage and an output voltage set value, which is defined by a set value determination table registered in the set value determining means of FIG. 7 and a continuous function formula. It is a circuit diagram which shows 4th embodiment of the power supply device of this invention. FIG. 10 is a diagram showing a set value determination table registered in the set value determination means of FIG. 9 and designation of a constant voltage generating circuit (center value of constant voltage and allowable error) for each trimmer voltage range. 10 is a graph showing a relationship between a trimmer voltage and an output voltage set value, which is defined by a set value determination table registered in the set value determination means of FIG. 9 and a continuous function formula. It is a circuit diagram which shows the modification of the power supply device of 3rd embodiment. It is a circuit diagram which shows the modification of the power supply device of 4th embodiment. A circuit diagram showing a configuration in which a fixed resistance element is connected to a trimmer terminal of a conventional power supply device (a), a circuit diagram showing a configuration in which a constant voltage generation circuit is connected, and a circuit showing a configuration in which a variable power supply device is connected. It is a figure (c).

  Hereinafter, the power supply device 26 which is the first embodiment of the present invention will be described with reference to FIGS. 1 to 3. Here, the configuration of the portion externally connected to the power supply device 26 will be described with the same reference numerals as those of the conventional configuration (FIG. 14).

  The power supply device 26 is a switching type power supply device, and includes a power conversion circuit and an output voltage control circuit 28 (not shown). The output voltage control circuit 28 receives the error amplification circuit 28a for amplifying the difference between the output voltage signal Vo1 and the reference voltage Vk, and the control signal Vs output by the error amplification circuit 28a, and outputs the output voltage signal Vo1 and the reference voltage Vk. And a switching control circuit 28b that controls the power conversion circuit so that the difference approaches zero. The reference voltage generating circuit 30 for generating the reference voltage Vk receives the output voltage setting information J (Vr) from the setting value determining means 32 described later, and adjusts the value of the reference voltage Vk based on this.

  The power supply device 26 is provided with a trimmer terminal 18 as an external connection terminal for changing the output voltage setting value Vr. The voltage generated at the trimmer terminal 18 (hereinafter referred to as the trimmer voltage Vtrm) is configured to be changed by connecting the fixed resistance element 20 to the trimmer terminal 18.

  The set value determination means 32 is a block provided in the digital processor, in which set value determination tables Ta and Tb defining the relationship between the trimmer voltage Vtrm and the output voltage set value Vr are registered in advance.

  As shown in FIG. 2A, the set value determination table Ta defines a plurality of ranges A1, A2, ... Which divide the range (≦ Vx) of the trimmer voltage Vtrm into a predetermined width. Different output voltage setting values Vr (A1), Vr (A2), ... Are assigned to A1, A2, ....

  Further, the nominal value and the tolerance of the fixed resistance element 20 connected externally are specified for each output voltage set value Vr (A1), Vr (A2), .... For example, with respect to the output voltage set value Vr (A1), it is specified to connect the fixed resistance element 20 having a nominal value Ra1 [Ω] and a tolerance of ± 1%. Similarly, for the output voltage setting value Vr (A2), a fixed resistance with a nominal value of Ra2 (1) [Ω] and a tolerance of ± 1% and a nominal resistance of Ra2 (2) [Ω] with a tolerance of ± 1% It is specified to connect a fixed resistance element 20 in parallel with a fixed resistance of 1%.

  Further, the widths of the ranges A1, A2, ... Of the trimmer voltage Vtrm are the variation of each trimmer voltage Vtrm when the designated fixed resistance element 20 is externally connected and its resistance value varies within the tolerance range. The widths ΔV (Ra1), ΔV (Ra2), ... Are set within the ranges A1, A2 ,.

  The output voltage setting values Vr (A1), Vr (A2), ... Are used in various fields such as 1.0V, 1.2V, 1.5V, 1.8V, 2.0V, 2.5V, 3.3V, 5V. A general voltage is selected.

  In the set value determination table Tb, as shown in FIG. 2B, a plurality of ranges B1, B2, ... Which define a range (≦ Vx) of the trimmer voltage Vtrm into a predetermined width are defined, and each range is defined. Different output voltage setting values Vr (B1), Vr (B2), ... Are assigned to B1, B2, ....

  Further, the nominal value and the tolerance of the fixed resistance element 20 connected externally are specified for each output voltage set value Vr (B1), Vr (B2), .... For example, with respect to the output voltage setting value Vr (B1), it is specified to connect the fixed resistance element 20 having a nominal value Rb1 [Ω] and a tolerance of ± 2%. Similarly, for the output voltage set value Vr (B2), a fixed resistance with a nominal value of Rb2 (1) [Ω] and a tolerance of ± 2% and a nominal resistance of Rb2 (2) [Ω] with a tolerance of ± 2% It is specified to connect a fixed resistance element 20 in parallel with a fixed resistance of 2%.

  Further, the widths of the ranges B1, B2, ... Of the trimmer voltage Vtrm are the variation of each trimmer voltage Vtrm when the designated fixed resistance element 20 is externally connected and its resistance value varies within the tolerance range. The widths ΔV (Rb1), ΔV (Rb2), ... Are set within the ranges B1, B2 ,.

  In the set value determination table Tb, in order to make the fixed resistance element 20 prepared by the user inexpensive and easy to obtain, the tolerance of the fixed resistance element 20 is specified more loosely than in the set value determination table Ta. Therefore, as shown in FIGS. 3 (a) and 3 (b), the widths of the ranges B1, B2, ... Are wider than the set value determination table Ta, and accordingly, the ranges B1, B2 ,. The number of and the number of output voltage set values Vr (B1), Vr (B2), ... Are smaller than the set value determination table Ta. For the output voltage set values Vr (B1), Vr (B2), ..., Especially used voltages are selected from the above-mentioned general voltages.

  The set value determination means 32 detects the trimmer voltage Vtrm, determines the output voltage set value Vr based on the regulation of the set value determination table Ta or Tb, and sets the determined content as the output voltage setting information J (Vr) as the reference voltage. The operation of transmitting to the generation circuit 30 is performed.

  Furthermore, the power supply device 26 is provided with a table selection terminal 34 for acquiring the table selection information J (table) from the external device 36 as an external connection terminal. The table selection information J (table) is information in which the user has specified a setting value determination table to be used when determining the output voltage setting value Vr, and the setting value determination means 32 stores the table selection information J (table). Then, the output voltage setting value Vr is determined using the designated setting value determination table (Ta or Tb).

  The set value determination means 32 outputs when the detected trimmer voltage Vtrm is not included in the range specified in the specified set value determination table (Ta or tb) (that is, when Vtrm> Vx). Determine the voltage setting value to a safe value below a certain level. This makes it possible to protect the internal circuits of the load 16 and the power supply device 26 when the user erroneously connects the fixed resistance element 20 not specified.

  Next, the usage method and operation of the power supply device 26 will be described. For example, when the user wants to set the output voltage setting value Vr to Vr (A1), the user connects the fixed resistance element 20 having a nominal value Ra1 [Ω] and a tolerance of ± 1% to the trimmer terminal 18, and from the external device 36, The table selection information J (table) having the content of “select the setting value determination table Ta” is transmitted to the setting value determination means 32 through the table selection terminal 34. Then, when the operation of the power supply device 26 is turned on, a predetermined trimmer voltage Vtrm is generated.

  The trimmer voltage Vtrm surely falls within the range of V1a <Vtrm ≦ V2a even if the resistance value of the fixed resistance element 20 varies within the tolerance range. Therefore, the set value determination means 32 determines that the trimmer voltage Vtrm belongs to the range A1 of the set value determination table Ta, determines the output voltage set value Vr to Vr (A1), and outputs the output voltage setting information J ( Vr) is transmitted to the reference voltage generation circuit 30.

  The reference voltage generation circuit 30 adjusts the value of the reference voltage Vk so that the output voltage Vo becomes Vr (A1), and the output voltage control circuit 28 performs a switching operation so that the output voltage signal Vo1 approaches the reference voltage Vk. Control. As a result, the output voltage Vo becomes exactly Vr (A1).

  Similarly, for example, when the user wants to set the output voltage set value Vr to Vr (B1), the user connects the fixed resistance element 20 having a nominal value Rb1 [Ω] and a tolerance of ± 2% to the trimmer terminal 18, and The device 36 transmits the table selection information J (table) having the content of “selecting the setting value determination table Tb” to the setting value determining means 32 through the table selection terminal 34. As a result, the output voltage Vo becomes exactly Vr (B1).

  As described above, according to the power supply device 26, the trimmer voltage Vtrm generated at the trimmer terminal 18 is detected, and the output voltage set value Vr is determined based on the unique set value determination table Ta or Tb. Even if the resistance value of the fixed resistance element 20 to be connected varies within the tolerance range, the desired output voltage Vo can be accurately obtained.

  Next, the power supply device 38 which is the second embodiment of the present invention will be described with reference to FIGS. Here, the same components as those of the power supply device 26 described above are denoted by the same reference numerals, and description thereof will be omitted.

  The power supply device 38 is a switching-type power supply device similar to the power supply device 26. As shown in FIG. 4, the power supply device 38 is different from the power supply device 26 in that a set value determination means 40 is provided instead of the set value determination means 32. That is the point. Further, in the case of the power supply device 38, the voltage generated at the trimmer terminal 18 is provided with a constant voltage generating circuit 22 between the output terminals 12 and 14, and the constant voltage generating circuit 22 generates a predetermined constant voltage. Can be changed by inputting to the trimmer terminal 18. That is, in the case of the power supply device 38, the constant voltage generated by the constant voltage generating circuit 22 becomes the trimmer voltage Vtrm as it is.

  The set value determination means 40 is a block provided in the digital processor, in which set value determination tables Tc and Td defining the relationship between the trimmer voltage Vtrm and the output voltage set value Vr are registered in advance.

  As shown in FIG. 5A, the set value determination table Tc defines a plurality of ranges C1, C2, ... Which divide the range (≦ Vx) of the trimmer voltage Vtrm into a predetermined width. Different output voltage setting values Vr (C1), Vr (C2), ... Are assigned to C1, C2, ....

  Further, for each output voltage set value Vr (C1), Vr (C2), ..., The center value and the allowable error of the externally input constant voltage are specified. For example, with respect to the output voltage setting value Vr (C1), it is specified that a constant voltage having a central value Vc1 [V] and an allowable error of ± 3% is input. Similarly, with respect to the output voltage setting value Vr (C2), it is specified that a constant voltage having a central value Vc2 [V] and an allowable error of ± 3% is input.

  Further, the width of the range C1, C2, ... Of the trimmer voltage Vtrm is such that when the specified constant voltage is externally input, the width of the fluctuation of the constant voltage (variation of the trimmer voltage Vtrm) is in each range C1, C2. , ... is set to fit within. For the output voltage set values Vr (C1), Vr (C2), ..., General voltages used in various fields are selected.

  As shown in FIG. 5B, the set value determination table Td defines a plurality of ranges D1, D2, ... Which divide the range (≦ Vx) of the trimmer voltage Vtrm into a predetermined width. Different output voltage setting values Vr (D1), Vr (D2), ... Are assigned to D1, D2, ....

  Further, for each output voltage set value Vr (D1), Vr (D2), ..., The center value and the allowable error of the externally input constant voltage are designated in advance. For example, with respect to the output voltage set value Vr (D1), it is specified that a constant voltage having a central value Vd1 [V] and an allowable error of ± 5% is input. Similarly, with respect to the output voltage setting value Vr (D2), it is specified that a constant voltage having a central value Vd2 [V] and an allowable error of ± 5% is input.

  Further, the width of the range D1, D2, ... Of the trimmer voltage Vtrm is such that when the specified constant voltage is externally input, the width of the fluctuation of the constant voltage (variation of the trimmer voltage Vtrm) is in each range D1, D2. , ... is set to fit within.

  In the set value determination table Td, in order to configure the constant voltage generation circuit 22 prepared by the user with inexpensive and easily available parts, the specification of the constant voltage tolerance is looser than that of the set value determination table Tc. ing. Therefore, as shown in FIGS. 6 (a) and 6 (b), the width of each range D1, D2, ... Is wider than the set value determination table Tc, and accordingly the ranges D1, D2 ,. The number of and the number of output voltage set values Vr (D1), Vr (D2), ... Are smaller than the set value determination table Tc. As the output voltage set values Vr (D1), Vr (D2), ..., Especially used voltages are selected from the above-mentioned general voltages.

  The set value determination means 40 detects the trimmer voltage Vtrm, determines the output voltage set value Vr based on the regulation of the set value determination table Tc or Td, and uses the determined content as the output voltage setting information J (Vr) as the reference voltage. The operation of transmitting to the generation circuit 30 is performed.

  Next, the usage method and operation of the power supply device 26 will be described. For example, when the user wants to set the output voltage setting value Vr to Vr (C1), the user connects the trimmer terminal 18 with a constant voltage generating circuit 22 that outputs a constant voltage with a center value of Vc1 [V] and a tolerance of ± 3%. Then, the external device 36 is caused to transmit the table selection information J (table) having the content of “selecting the setting value determination table Tc” to the setting value determining means 40 through the table selection terminal 34. Then, the operation of the power supply device 38 is turned on.

  The trimmer voltage Vtrm surely falls within the range of V1c <Vtrm ≦ V2c even if the constant voltage varies within the allowable error range. Therefore, the set value determination means 40 determines that the trimmer voltage Vtrm belongs to the range C1 of the set value determination table Tc, determines the output voltage set value Vr as Vr (C1), and outputs the output voltage setting information J ( Vr) is transmitted to the reference voltage generation circuit 30.

  The reference voltage generation circuit 30 adjusts the value of the reference voltage Vk so that the output voltage Vo becomes Vr (C1), and the output voltage control circuit 28 performs a switching operation so that the output voltage signal Vo1 approaches the reference voltage Vk. Control. As a result, the output voltage Vo becomes exactly Vr (C1).

  Similarly, for example, when the user wants to set the output voltage set value Vr to Vr (D1), the user trims the constant voltage generating circuit 22 that outputs a constant voltage with a center value of Vd1 [V] and a tolerance of ± 5%. Connected to the terminal 18, the external device 36 transmits the table selection information J (table) having the content of “select the setting value determination table Td” to the setting value determining means 40 through the table selection terminal 34. As a result, the output voltage Vo becomes exactly Vr (D1).

  As described above, according to the power supply device 38, the trimmer voltage Vtrm generated at the trimmer terminal 18 is detected, and the output voltage set value Vr is determined based on the unique set value determination table Tc or Td. Even if the constant voltage of the connected constant voltage generation circuit 22 varies within the allowable error range, the desired output voltage Vo can be accurately obtained.

  Next, a power supply device 42 according to a third embodiment of the present invention will be described with reference to FIGS. 7 and 8. Here, the same components as those of the power supply device 26 are designated by the same reference numerals and the description thereof will be omitted.

  The power supply device 42 is a switching type power supply device similar to the power supply device 26. As shown in FIG. 7, the power supply device 26 is different from the power supply device 26 in that a set value determination means 44 is provided instead of the set value determination means 32. That is the point.

  Further, in the case of the power supply device 42, as a method of changing the trimmer voltage Vtrm, a method of connecting the fixed resistance element 20 to the trimmer terminal 18 and a method of increasing the constant voltage intended by the user as shown in FIG. A variable power supply device 24 that outputs with high accuracy is prepared, and both of the methods of inputting this constant voltage to the trimmer terminal 18 can be used. When the latter method is used, the constant voltage output from the variable power supply device 24 becomes the trimmer voltage Vtrm as it is.

  The set value determination means 44 is a block provided in the digital processor, and in advance, the set value determination table Ta and a continuous function formula S1 defining the relationship between the trimmer voltage Vtrm and the output voltage set value Vr are registered. Has been done. The set value determination table Ta is a table for the range of the trimmer voltage Vtrm ≦ Vx as described above, and does not cover the range of the trimmer voltage Vtrm> Vx. On the other hand, the continuous function formula S1 is a formula for the range of trimmer voltage Vtrm> Vx, and does not cover the range of trimmer voltage Vtrm ≦ Vx.

  The set value determination means 44 detects the trimmer voltage Vtrm, and as shown in FIG. 8, when the detected trimmer voltage Vtrm is Vx or less, determines the output voltage set value Vr based on the regulation of the set value determination table Ta. If it exceeds Vx, the output voltage set value Vr is determined based on the continuous function formula S1. Then, an operation of transmitting the determined contents as the output voltage setting information J (Vr) to the reference voltage generating circuit 30 is performed.

Next, a method of using the power supply device 42 will be described. When the user uses "the output voltage Vo is once set and then not changed", the user connects a predetermined fixed resistance element 20 to the trimmer terminal 18 and uses the trimmer voltage Vtrm≤Vx. As a result, the same effect as that of the power supply device 26 can be obtained. On the other hand, in the case of using "to continuously change the output voltage Vo while the power supply device 42 is operating", the constant voltage output from the variable power supply device 24 is input to the trimmer terminal 18 and the trimmer voltage Vtrm> Vx Used in the range. As a result, the output voltage set value Vr can be continuously changed, and the output voltage Vo can be finely changed.

As described above, according to the power supply device 42, either of the usage of “setting the output voltage Vo once and not changing thereafter” and the usage of “ continuously varying the output voltage Vo while the power supply device is operating” Can also be accommodated.

  Next, a power supply device 46 according to a fourth embodiment of the present invention will be described based on FIGS. 9 to 11. Here, the same components as those of the power supply device 26 are designated by the same reference numerals and the description thereof will be omitted.

  The power supply device 46 is a switching type power supply device similar to the power supply device 26. As shown in FIG. 9, a setting value determining means 48 is provided instead of the setting value determining means 32. And that a mode selection terminal 50, which is a new external connection terminal, is provided.

  Further, in the case of the power supply device 46, as a method of changing the trimmer voltage Vtrm, a method of connecting the fixed resistance element 20 to the trimmer terminal 18 and a method of increasing the constant voltage intended by the user as shown in FIG. A variable power supply device 24 that outputs with high accuracy is prepared, and both of the methods of inputting this constant voltage to the trimmer terminal 18 can be used. When the latter method is used, the constant voltage output from the variable power supply device 24 becomes the trimmer voltage Vtrm as it is.

  The set value determination means 48 is a block provided in the digital processor, in which a set value determination table Te and a continuous function formula S2 defining the relationship between the trimmer voltage Vtrm and the output voltage set value Vr are registered in advance. There is.

  As shown in FIG. 10, the set value determination table Te defines a plurality of ranges E1, E2, ... Which divide the range of the trimmer voltage Vtrm into a predetermined width, and each range E1, E2 ,. Different output voltage setting values Vr (E1), Vr (E2), ... Are assigned to.

  Further, the nominal value and the tolerance of the fixed resistance element 20 connected externally are specified for each output voltage set value Vr (E1), Vr (E2), .... For example, with respect to the output voltage setting value Vr (E1), it is specified to connect the fixed resistance element 20 having a nominal value Re1 [Ω] and a tolerance of ± 1%. Similarly, for the output voltage setting value Vr (E2), a fixed resistance with a nominal value of Re2 (1) [Ω] and a tolerance of ± 1% and a nominal value of Re2 (2) [Ω] with a tolerance of ± 1% It is specified to connect a fixed resistance element 20 in parallel with a fixed resistance of 1%.

  Further, the widths of the ranges E1, E2, ... Of the trimmer voltage Vtrm are the variation of each trimmer voltage Vtrm when the designated fixed resistance element 20 is externally connected and its resistance value varies within the tolerance range. The widths ΔV (Re1), ΔV (Re2), ... Are set within the respective ranges E1, E2 ,.

  As shown in FIG. 11, the continuous function formula S2 is a formula applied to a range overlapping the range of the trimmer voltage Vtrm defined in the set value determination table Te, and is significantly different from the continuous function formula S1 shown in FIG. .

  The set value determination means 48 detects the trimmer voltage Vtrm, determines the output voltage set value Vr based on the regulation of the set value determination table Te or the continuous function formula S2, and outputs the determined content to the output voltage setting information J (Vr). Then, the operation of transmitting to the reference voltage generation circuit 30 is performed.

  The mode selection terminal 50 is an external connection terminal for acquiring the mode selection information J (mode) from the external device 36. Mode selection information J (mode) is either the first mode for determining the output voltage setting value Vr based on the setting value determination table or the second mode for determining the output voltage setting value Vr based on the continuous function formula. This is information that the user specifies. The set value determination means 48 receives the mode selection information J (mode) and determines the output voltage set value Vr in accordance with this.

  Next, a method of using the power supply device 46 will be described. The user connects the fixed resistance element 20 to the trimmer terminal 18 and uses the external device 36 to "select the first mode" when the user uses "the output voltage Vo is once set and then not changed". The mode selection information J (mode) of the contents is transmitted to the set value determination means 48 through the mode selection terminal 50. As a result, the same effect as that of the power supply device 26 can be obtained. On the other hand, in the case of using “variing the output voltage Vo while the power supply device 46 is operating”, the constant voltage output from the variable power supply device 24 is input to the trimmer terminal 18, and the external device 36 reads “second The mode selection information J (mode) having the content of “select a mode” is transmitted to the set value determination means 48 through the mode selection terminal 50. As a result, the output voltage set value Vr can be continuously changed, and the output voltage Vo can be finely changed.

  As described above, according to the power supply device 46, both the usage of “setting the output voltage Vo once and not changing thereafter” and the usage of “variing the output voltage Vo while the power supply device is operating” are supported. can do.

  The power supply device of the present invention is not limited to the above embodiment. For example, the power supply device 26 of the first embodiment has two set value determination tables in the set value determination means 32, but the number of set value determination tables may be any number. When the number is one, the table selection terminal 34 can be omitted. The same applies to the power supply device 38 of the second embodiment.

  In the power supply device 42 of the third embodiment, the set value determination means 44 is provided with one set value determination table, but a plurality of set value determination tables may be provided. For example, in the power supply device 42h shown in FIG. 12, the set value determination means 44h is provided with the set value determination tables Ta and Tb (both are in the range of the trimmer voltage Vtrm ≦ Vx). In this case, when the trimmer voltage Vtrm ≦ Vx, the table selection terminal 34 is provided like the power supply device 26 so that the setting value determination means 44h can determine which setting value determination table to use, and the external device 36 outputs the table. It is advisable to have a configuration that can acquire the selection information J (table).

  In the power supply device 46 of the fourth embodiment, the set value determination means 48 is provided with one set value determination table, but a plurality of set value determination tables may be provided. For example, in the power supply device 46h shown in FIG. 13, the set value determination means 48h is provided with set value determination tables Te and Tf. In this case, when the first mode (mode for determining the output voltage set value Vr based on the set value determination table) is selected, the set value determination means 48h can determine which set value determination table to use. As described above, the table selection information J (table) can be acquired from the external device 36 through the mode selection terminal 50. A table selection terminal 34 may be newly provided separately from the mode selection terminal 50.

  The power supply devices 42 and 46 of the third and fourth embodiments are provided with a set value determination table on the assumption that the fixed resistance element 20 is connected to the trimmer terminal 18, but the constant voltage generation circuit 22 is connected. You may provide the setting value determination table which assumed that.

  In each embodiment, when a plurality of set value determination tables are provided in the set value determination means, the set value determination table assuming that the fixed resistance element 20 is connected to the trimmer terminal 18 and the constant voltage generation circuit 22 are connected. It is possible to provide both of the setting value determination tables assuming that. As a result, it is possible to increase the choices of usage methods and further improve the convenience of the user.

  Besides, the fixed resistance element connected to the trimmer terminal may be configured by one fixed resistance, or may be configured by connecting a plurality of fixed resistances in series, parallel or series-parallel. Good. Further, the configuration of the constant voltage generating circuit connected to the trimmer terminal is not particularly limited and may be a configuration other than the constant voltage generating circuit 22. Further, the power conversion circuit is not limited to the switching system, and the configuration of the output voltage control circuit can be appropriately changed according to the configuration of the power conversion circuit.

10, 26, 38, 42, 42h, 46, 46h Power supply device 16 Load 18 Trimmer terminal 20 Fixed resistance element 22 Constant voltage generating circuit 24 Variable power supply device 32, 40, 44, 44h, 48, 48h Setting value determining means 34 Table Selection terminal 36 External device 50 Mode selection terminal Ta, Tb, Tc, Td, Te, Tf Setting value determination table S1, S2 Continuous function formula
Vo output voltage
Vr Output voltage setting value
Vtrm Trimmer voltage

Claims (8)

A trimmer terminal, which is an external connection terminal for changing the output voltage setting value,
Means for determining the output voltage setting value according to the trimmer voltage generated at the trimmer terminal, wherein the output voltage setting is based on a setting value determination table that defines the relationship between the trimmer voltage and the output voltage setting value. And a setting value determining means for determining the value,
In the set value determination table, a plurality of ranges in which the range of the trimmer voltage is divided into a predetermined width is defined, and the different output voltage set values are assigned to the ranges,
The set value determination means is provided with a plurality of the set value determination tables,
A power supply device comprising a table selection terminal which is an external connection terminal for selecting one of the setting value determination tables used when determining the output voltage setting value . When the trimmer voltage which is not included in the range defined in the setting value determination table is generated, the set value determining means according to claim 1 for determining the output voltage set value constant less safe value The power supply described. The set value determining means is further provided with a continuous function formula that defines the relationship between the trimmer voltage and the output voltage set value,
When the trimmer voltage which is not included in the range defined in the setting value determination table is generated, the set value determining means according to claim 1 for determining the output voltage set value based on the continuous function equation The power supply described. A trimmer terminal, which is an external connection terminal for changing the output voltage setting value,
Means for determining the output voltage setting value according to the trimmer voltage generated at the trimmer terminal, wherein the output voltage setting is based on a setting value determination table that defines the relationship between the trimmer voltage and the output voltage setting value. And a setting value determining means for determining the value ,
In the set value determination table, a plurality of ranges in which the range of the trimmer voltage is divided into a predetermined width is defined, and the different output voltage set values are assigned to the ranges,
The set value determining means is further provided with a continuous function formula that defines the relationship between the trimmer voltage and the output voltage set value,
A mode selection which is an external connection terminal for selecting one of a mode for determining the output voltage setting value based on the setting value determination table and a mode for determining the output voltage setting value based on the continuous function formula. A power supply device characterized in that a terminal is further provided. The set value determination means is provided with a plurality of the set value determination tables,
The power supply device according to claim 4, further comprising a table selection terminal which is an external connection terminal for selecting one of the setting value determination tables used when determining the output voltage setting value.   6. The mode selection terminal is also used as the table selection terminal, and the setting value determination table used when determining the output voltage setting value can be selected using the mode selection terminal. Power supply. A trimmer terminal, which is an external connection terminal for changing the output voltage setting value,
Means for determining the output voltage setting value according to the trimmer voltage generated at the trimmer terminal, wherein the output voltage setting is based on a setting value determination table that defines the relationship between the trimmer voltage and the output voltage setting value. And a setting value determining means for determining the value,
In the set value determination table, a plurality of ranges in which the range of the trimmer voltage is divided into a predetermined width is defined, and the different output voltage set values are assigned to the ranges,
The set value determining means is further provided with a continuous function formula that defines the relationship between the trimmer voltage and the output voltage set value,
When the trimmer voltage not included in the range defined in the set value determination table is generated, the set value determination unit determines the output voltage set value based on the continuous function formula. And power supply. The range of the output voltage set value determined based on the continuous function formula is wholly or partly overlapped with the range of the output voltage set value determined based on the set value determination table. Power supply.

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