Pulse voltage conversion circuit

Abstract

To provide a pulse voltage conversion circuit which has a function for adjusting pulse characteristics of an output pulse voltage (a pulse characteristic adjustment function).SOLUTION: A pulse voltage conversion circuit has: an input pulse power supply; an n-channel type MOSFET driven by the input pulse power supply; a high-side switch driven by the n-channel type MOSFET; and a high-side power supply connected to the high-side switch. The pulse voltage conversion circuit generates an output pulse voltage in accordance with an input pulse voltage inputted from the input pulse power supply. A pulse width adjustment circuit, which is constituted by a resistance division circuit made up of a first resister and a second resister, is connected between the input pulse power supply and the n-channel type MOSFET.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a pulse voltage conversion circuit, and more particularly to a pulse voltage conversion circuit suitable for use in converting an input pulse voltage into a pulse voltage (output pulse voltage) with a desired peak value, such as converting a low-voltage pulse voltage (input pulse voltage) such as the output level of a TTL (Transistor-Transistor Logic) or CMOS (Complementary MOS) into a high-voltage pulse voltage (output pulse voltage) with a desired peak value. [Background technology]

[0002] Conventionally, pulse voltage conversion circuits have been known that convert an input pulse voltage into a pulse voltage (output pulse voltage) of a desired peak value, such as converting a low-voltage pulse voltage (input pulse voltage) such as the output level of a TTL or CMOS into a high-voltage pulse voltage (output pulse voltage) of a desired peak value.

[0003] FIG. 1 shows a circuit configuration diagram of the above-mentioned conventional pulse voltage conversion circuit.

[0004] In the conventional pulse voltage conversion circuit 100 shown in FIG. 1, the peak value of the output pulse voltage Vout at the current output terminal 102 can be set to a desired value depending on the voltage value of the high-side power supply (V1) 104 and the voltage division ratio of the series-connected resistors (R4) 110 and (R5) 112 that make up the resistive divider circuit 108 connected to the high-side power supply (V1) 104 via the high-side switch (Q2) 106.

[0005] In this pulse voltage conversion circuit 100, an example is shown in which a PNP transistor is used as the high-side switch (Q2) 106.

[0006] More specifically, the high-side power supply (V1) 104 is connected to the emitter (E) of the high-side switch (Q2) 106 by a connection line 114.

[0007] In addition, a resistor (R4) 110 constituting the resistive divider circuit 108 is connected to the collector (C) of the high-side switch (Q2) 106 and the current output terminal 102, and connects the high-side power supply (V1) 104 and the current output terminal 102 via the high-side switch (Q2) 106.

[0008] On the other hand, a resistor (R5) 112 that constitutes the resistive divider circuit 108 connects the current output terminal 102 to the ground.

[0009] In this pulse voltage conversion circuit 100, the high-side switch (Q2) 104 is controlled to turn ON / OFF in accordance with the input pulse voltage Vin of the input pulse power supply 116 connected to the base (B) of the high-side switch (Q2) 106, thereby generating the output pulse voltage Vout.

[0010] Furthermore, the pulse voltage conversion circuit 100 has an N-channel MOSFET (Q1) 118 connected between the input pulse power supply 116 and the base (B) of the high-side switch (Q2) 106, and this N-channel MOSFET (Q1) 118 controls the base voltage of the high-side switch (Q2) 106 in accordance with the input pulse voltage Vin generated by the input pulse power supply 116.

[0011] In the pulse voltage conversion circuit 100, a pull-down resistor (R1) 122 connected to ground is connected to a connection line 120 that connects the input pulse power supply 116 and the gate (G) of the N-channel MOSFET (Q1) 118.

[0012] In addition, in the pulse voltage conversion circuit 100, an RC parallel circuit formed by connecting a resistor (R2) 124 and a capacitor (C1) 126 in parallel is connected between the drain (D) of the N-channel MOSFET (Q1) 118 and the base (B) of the high-side switch (Q2) 106.

[0013] Furthermore, in the pulse voltage conversion circuit 100, a resistor (R3) 130 is connected between a connection line 114 that connects the high-side power supply (V1) 104 and the emitter (E) of the high-side switch (Q2) 106 and a connection line 128 that connects the above-mentioned RC parallel circuit and the base (B) of the high-side switch (Q2) 106, and the connection line 114 and the connection line 128.

[0014] In the above configuration, first, the operation at the time of pulse rise during pulse voltage conversion in the pulse voltage conversion circuit 100 will be described.

[0015] That is, in this pulse voltage conversion circuit 100, when the input pulse voltage Vin generated by the input pulse power supply 116 rises, the gate (G) of the N-channel MOSFET (Q1) 118 is driven by the input pulse power supply 116, and the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 rises.

[0016] When the potential of the gate-source voltage Vgs exceeds the threshold voltage of the N-channel MOSFET (Q1) 118, the drain-source of the N-channel MOSFET (Q1) 118 becomes conductive.

[0017] As a result, the base (B) of the high-side switch (Q2) 106 is driven by the N-channel MOSFET (Q1) 118, and the base potential of the high-side switch (Q2) 106 drops from the potential of the high-side power supply (V1) 104 to a value obtained by dividing the potential of the high-side power supply (V1) 104 by the resistors (R2) 124 and (R3) 130.

[0018] When the base-emitter voltage Vbe of the high-side switch (Q2) 106 exceeds the threshold voltage of the high-side switch (Q2) 106 (which is a negative voltage in this pulse voltage conversion circuit 100), the collector-emitter of the high-side switch (Q2) 106 becomes conductive, and a current corresponding to the base-emitter voltage Vbe described above is supplied to a resistive divider circuit formed by resistors (R4) 110 and (R5) 112.

[0019] As a result, the potential of the high-side power supply (V1) 104 is divided by the resistor (R4) 110 and the resistor (R5) 112, and the divided potential rises as the output pulse voltage Vout at the current output terminal .

[0020] Here, the capacitor (C1) 126 connected in parallel to the resistor (R2) 124 improves (speeds up) the collector-emitter conduction response of the high-side switch (Q2) 106 in response to the drain-source conduction of the N-channel MOSFET (Q1) 118.

[0021] Next, the operation of the pulse voltage conversion circuit 100 described above at the time of pulse falling during pulse voltage conversion will be described.

[0022] That is, in this pulse voltage conversion circuit 100, when the input pulse voltage Vin generated by the input pulse power supply 116 falls, the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 falls.

[0023] When the potential of the gate-source voltage Vgs falls below the threshold voltage of the N-channel MOSFET (Q1) 118, conduction between the drain and source of the N-channel MOSFET (Q1) 118 is cut off.

[0024] As a result, the base potential of the high-side switch (Q2) 106 rises from the value obtained by dividing the potential of the high-side power supply (V1) 104 by the resistor (R2) 124 and the resistor (R3) 130 to the potential of the high-side power supply (V1) 104.

[0025] When the base-emitter voltage Vbe of the high-side switch (Q2) 106 falls below the threshold voltage of the high-side switch (Q2) 106 (which is a negative voltage in this pulse voltage conversion circuit 100), conduction between the collector and emitter of the high-side switch (Q2) 106 is cut off, and the supply of current to the resistive divider circuit formed by resistors (R4) 110 and (R5) 112 is stopped.

[0026] As a result, the output pulse voltage Vout at the current output terminal 102 falls.

[0027] By the operation described above, the pulse voltage conversion circuit 100 converts the input pulse voltage Vin generated by the input pulse power supply 116 into an output pulse voltage Vout having a desired peak value.

[0028] In the conventional pulse voltage conversion circuit 100 described above, the pulse characteristics (peak value, pulse width, rise time, and fall time) of the output pulse voltage Vout depend on the characteristics (threshold voltage, base terminal capacitance, etc.) of the high-side switch (Q2) 106, the characteristics (threshold voltage, gate terminal capacitance, etc.) of the N-channel MOSFET (Q1) 118, which is an element for controlling the base voltage of the high-side switch (Q2) 106, and constants of the peripheral circuits (pull-down resistor (R1) 122, resistor (R2) 124, resistor (R3) 130, resistor (R4) 110, resistor (R5) 112, and capacitor (C1) 126).

[0029] 2(a)(b)(c)(d), FIG. 3(a')(b')(c')(d'), and FIG. 4(a'')(b'')(c'')(d'') show the transitions of the input pulse voltage Vin, the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118, the base-emitter voltage Vbe of the high-side switch (Q2) 106, and the output pulse voltage Vout until the input pulse voltage Vin is converted into the output pulse voltage Vout in the conventional pulse voltage conversion circuit 100 described above.

[0030] More specifically, Figures 2(a), 3(a') and 4(a'') show the change in the voltage waveform of the input pulse voltage Vin until it is converted into the output pulse voltage Vout.

[0031] 2(b), 3(b'), and 4(b'') show the change in the voltage waveform of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 until the input pulse voltage Vin is converted into the output pulse voltage Vout.

[0032] Furthermore, Figures 2(c), 3(c') and 4(c'') show the change in the voltage waveform of the base-emitter voltage Vbe of the high-side switch (Q2) 106 until the input pulse voltage Vin is converted into the output pulse voltage Vout.

[0033] Furthermore, Figures 2(d), 3(d') and 4(d'') show the transition of the voltage waveform of the output pulse voltage Vout until the input pulse voltage Vin is converted into the output pulse voltage Vout.

[0034] First, an explanation will be given with reference to FIGS. 2(a), (b), (c), and (d). FIGS. 2(a), (b), (c), and (d) show an example of pulse voltage conversion when the threshold voltage of the N-channel MOSFET (Q1) 118, the gate terminal capacitance of the N-channel MOSFET (Q1) 118, the threshold voltage of the high-side switch (Q2) 106, and the base terminal capacitance of the high-side switch (Q2) 106 are all at reference values.

[0035] As described above, FIG. 2(a) shows the change in the voltage waveform of the input pulse voltage Vin, FIG. 2(b) shows the change in the voltage waveform of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118, FIG. 2(c) shows the change in the voltage waveform of the base-emitter voltage Vbe of the high-side switch (Q2) 106, and FIG. 2(d) shows the change in the voltage waveform of the output pulse voltage Vout.

[0036] Here, when the input pulse voltage Vin having the voltage waveform shown in FIG. 2(a) is input, as shown in FIG. 2(b), the rise time of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 is slowed down by the output impedance of the input pulse power supply 116, which is the signal source of the input pulse voltage Vin, and the gate terminal capacitance of the N-channel MOSFET (Q1) 118 (see part (A) of FIG. 2(b)), and the fall time is slowed down by the pull-down resistor (R1) 122 and the gate terminal capacitance of the N-channel MOSFET (Q1) 118 (see part (B) of FIG. 2(b)).

[0037] As shown in FIG. 2( c), the rise time (from 0 V to a negative voltage) of the base-emitter voltage Vbe of the high-side switch (Q2) 106 is slowed down not only by the slow rise time of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 but also by the resistor (R2) 124 and the base terminal capacitance of the high-side switch (Q2) 106 (see part (c) of FIG. 2( c)). The fall time (from a negative voltage to 0 V) ​​is slowed down not only by the slow fall time of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 but also by the resistor (R3) 130 and the base terminal capacitance of the high-side switch (Q2) 106 (see part (d) of FIG. 2).

[0038] Furthermore, because the rise time of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 is slowed, the start of the rise (from 0 V to a negative voltage) of the base-emitter voltage Vbe of the high-side switch (Q2) 106 is delayed by the time from when the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 starts to rise until it exceeds the threshold voltage of the N-channel MOSFET (Q1) 118 (see part (e) of FIG. 2 ). Furthermore, because the fall time of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 is slowed, the start of the fall (from a negative voltage to 0 V) ​​of the base-emitter voltage Vbe of the high-side switch (Q2) 106 is delayed by the time from when the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 starts to fall until it falls below the threshold voltage of the N-channel MOSFET (Q1) 118 (see part (f) of FIG. 2(c)).

[0039] As shown in FIG. 2(d), the rise time Ton of the output pulse voltage Vout is not only slowed down by the rise time (from 0 V to negative voltage) of the base-emitter voltage Vbe of the high-side switch (Q2) 106, but is further slowed down by the resistor (R4) 110 and the input capacitance of the load connected to the output pulse voltage Vout (see part (g) of FIG. 2(d)). The fall time Toff is not only slowed down by the fall time (from negative voltage to 0 V) ​​of the base-emitter voltage Vbe of the high-side switch (Q2) 106, but is further slowed down by the resistor (R5) 112 and the input capacitance of the load connected to the output pulse voltage Vout (see part (h) of FIG. 2(d)).

[0040] Furthermore, because the rise time of the base-emitter voltage Vbe of the high-side switch (Q2) 106 (from 0 V to negative voltage) is slowed down, the rise time of the output pulse voltage Vout is delayed by the time from when the base-emitter voltage Vbe of the high-side switch (Q2) 106 starts to rise until it exceeds the threshold voltage of the high-side switch (Q2) 106 (see part (i) in FIG. 2(d)). Also, because the fall time of the base-emitter voltage Vbe of the high-side switch (Q2) 106 (from negative voltage to 0 V) ​​is slowed down, the fall time of the output pulse voltage Vout is delayed by the time from when the base-emitter voltage Vbe of the high-side switch (Q2) 106 starts to fall until it falls below the threshold voltage of the high-side switch (Q2) 106 (see part (j) in FIG. 2(d)).

[0041] As described above, the output pulse voltage Vout has the pulse characteristics shown in FIG. 2(d).

[0042] In contrast, Figures 3(a'), (b'), (c'), and (d') show an example of pulse voltage conversion when the threshold voltage of the N-channel MOSFET (Q1) 118 is higher than the reference value and the threshold voltage of the high-side switch (Q2) 106 is lower than the reference value.

[0043] As described above, FIG. 3(a') shows the change in the voltage waveform of the input pulse voltage Vin, FIG. 3(b') shows the change in the voltage waveform of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118, FIG. 3(c') shows the change in the voltage waveform of the base-emitter voltage Vbe of the high-side switch (Q2) 106, and FIG. 3(d') shows the change in the voltage waveform of the output pulse voltage Vout.

[0044] In addition, in Figures 3(a'), (b'), (c'), and (d'), the parts corresponding to parts (A), (B), (C), (D), (E), (F), (G), (H), (H), (I), (Ii), and (Ju) explained above with reference to Figures 2(a), (b), (c), and (d) are indicated by adding "'" and being represented as part (A'), part (B'), part (C), part (D), part (E), part (F), part (G), part (H), part (Ii), part (Ii), and part (Ju').

[0045] On the other hand, Figures 4(a''), (b''), (c''), and (d'') show an example of pulse voltage conversion when the threshold voltage of the N-channel MOSFET (Q1) 118 is lower than the reference value and the threshold voltage of the high-side switch (Q2) 106 is higher than the reference value.

[0046] As described above, Figure 4(a'') shows the change in the voltage waveform of the input pulse voltage Vin, Figure 4(b'') shows the change in the voltage waveform of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118, Figure 4(c'') shows the change in the voltage waveform of the base-emitter voltage Vbe of the high-side switch (Q2) 106, and Figure 4(d'') shows the change in the voltage waveform of the output pulse voltage Vout.

[0047] Furthermore, in Figures 4(a'')(b'')(c'')(d''), the parts corresponding to parts (A), (B), (C), (D), (E), (F), (G), (H), (H), (I), (Il) and (Ju) described above with reference to Figures 2(a)(b)(c)(d) are indicated by adding "'' to parts (A''), (B''), (C''), (D), (E), (F), (G), (H), (Il), (Il), and (Ju'').

[0048] Here, when the threshold voltage of the N-channel MOSFET (Q1) 118 shown in FIGS. 3(a'), (b'), (c'), and (d') is higher than the reference value and the threshold voltage of the high-side switch (Q2) 106 is lower than the reference value, there is no change in the rise time Ton and fall time Toff, but the pulse width Tpw is shorter, compared to when the threshold voltage of the N-channel MOSFET (Q1) 118, the gate terminal capacitance of the N-channel MOSFET (Q1) 118, the threshold voltage of the high-side switch (Q2) 106, and the base terminal capacitance of the high-side switch (Q2) 106 shown in FIGS. 2(a), (b), (c), and (d) are all at their reference values.

[0049] On the other hand, when the threshold voltage of the N-channel MOSFET (Q1) 118 shown in FIGS. 4(a''), (b''), (c''), and (d'') is lower than the reference value and the threshold voltage of the high-side switch (Q2) 106 is higher than the reference value, there is no change in the rise time Ton and fall time Toff, but the pulse width Tpw is longer, compared to when the threshold voltage of the N-channel MOSFET (Q1) 118, the gate terminal capacitance of the N-channel MOSFET (Q1) 118, the threshold voltage of the high-side switch (Q2) 106, and the base terminal capacitance of the high-side switch (Q2) 106 are at their reference values, as shown in FIGS. 2(a), (b), (c), and (d).

[0050] That is, as is clear from the above description, the conventional pulse voltage conversion circuit 100 described above has a problem in that the pulse characteristics of the output pulse voltage Vout change due to variations in the characteristics of the N-channel MOSFET (Q1) 118 and the high-side switch (Q2) 106 among the individual devices.

[0051] Similarly, as is clear from the above explanation, the conventional pulse voltage conversion circuit 100 described above had the problem that the pulse characteristics of the output pulse voltage Vout would change due to variations in the constants of the peripheral circuits (pull-down resistor (R1) 122, resistor (R2) 124, resistor (R3) 130, resistor (R4) 110, resistor (R5) 112, and capacitor (C1) 126).

[0052] It is known that changes in the pulse characteristics of the output pulse voltage Vout due to variations in the constants of the peripheral circuits can be largely offset by changing (adjusting) the constants of the peripheral circuits.

[0053] However, the change in the pulse characteristics of the output pulse voltage Vout caused by the individual variations in the characteristics of the N-channel MOSFET (Q1) 118 and the high-side switch (Q2) 106 is not something that can be easily solved by simply replacing the N-channel MOSFET (Q1) 118 or the high-side switch (Q2) 106.

[0054] In other words, since products (components) within the same lot often have similar characteristics, when implementing products (components) within the same lot that have characteristics of a specified standard value, even if the products (components) within the lot are interchanged, it is unlikely that the desired pulse characteristics will be obtained.

[0055] Although it may be possible to obtain the desired pulse characteristics by purchasing parts in multiple lots and repeatedly replacing them, this creates a new problem of increased manufacturing costs due to increased parts costs and labor required for replacement.

[0056] In addition, the prior art that the applicant of the present application knew at the time of filing the patent application is not an invention related to an invention publicly known in a literature, and therefore there is no prior art literature information to be described in the present specification. Summary of the Invention [Problem to be solved by the invention]

[0057] The present invention has been made in consideration of the various defects and problems in the conventional technology as described above, and its object is to provide a pulse voltage conversion circuit having a function of adjusting the pulse characteristics of an output pulse voltage (pulse characteristics adjustment function). [Means for solving the problem]

[0058] In order to achieve the above object, the pulse voltage conversion circuit according to the present invention has, in addition to the circuit configuration of a conventional pulse voltage conversion circuit, a pulse characteristics adjustment circuit for adjusting the pulse characteristics of the output pulse voltage.

[0059] That is, the pulse voltage conversion circuit according to the present invention is a pulse width adjustment circuit that is a pulse characteristics adjustment circuit, and is provided with a resistive divider circuit (pulse width adjustment circuit) between an input pulse power supply that is a signal source of an input pulse voltage and an N-channel MOSFET, for adjusting the pulse width of an output pulse voltage when the threshold voltage of the N-channel MOSFET changes.

[0060] Furthermore, the pulse voltage conversion circuit according to the present invention is configured so that a resistor-capacitor circuit (RC circuit) (pulse rise time adjustment circuit) is provided between the input pulse power supply, which is the signal source of the input pulse voltage, and the N-channel MOSFET as a pulse rise time adjustment circuit, which is a pulse characteristics adjustment circuit, for adjusting the pulse rise time of the output pulse voltage when the gate terminal capacitance of the N-channel MOSFET changes.

[0061] Furthermore, the pulse voltage conversion circuit according to the present invention is configured such that a resistor and a charge power supply (pulse fall time adjustment circuit) are provided at the drain of the N-channel MOSFET as a pulse characteristics adjustment circuit, which adjusts the pulse fall time of the output pulse voltage when the base terminal capacitance of the high-side switch changes.

[0062] Furthermore, when the pulse voltage conversion circuit of the present invention is equipped with a pulse fall time adjustment circuit, it is provided with diodes (backflow prevention diodes) for preventing backflow of current to each power supply so that it can be used even when the potentials of the charge power supply and the high-side power supply are different.

[0063] Therefore, according to the pulse voltage conversion circuit of the present invention, by incorporating the above-mentioned pulse width adjustment circuit into a conventional pulse voltage conversion circuit, or by incorporating the above-mentioned pulse rise time adjustment circuit into a conventional pulse voltage conversion circuit, or by incorporating the above-mentioned pulse fall time adjustment circuit into a conventional pulse voltage conversion circuit, it becomes possible to adjust the pulse characteristics of the output pulse voltage.

[0064] Furthermore, according to the pulse voltage conversion circuit of the present invention, when the above-mentioned pulse fall time adjustment circuit is incorporated into a conventional pulse voltage conversion circuit, by incorporating a backflow prevention diode into the conventional pulse voltage conversion circuit, it becomes possible to prevent backflow of current to each power supply even when the potentials of the charge power supply and the high-side power supply are different.

[0065] The pulse voltage conversion circuit according to the present invention is effective when a design change is made by replacing N-channel MOSFETs or high-side switches with alternative components due to reasons such as the discontinuation of production, and when it is desired to obtain pulse characteristics equivalent to those of the output pulse voltage in the circuit before the design change, or when it is desired to adjust the pulse characteristics of the output pulse voltage by changing the constants of the peripheral circuitry to prevent changes in the pulse characteristics of the output pulse voltage due to variations in the characteristics of each component during mass production.

[0066] That is, the present invention provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in accordance with an input pulse voltage input from the input pulse power supply, wherein a pulse width adjustment circuit made up of a resistance divider circuit constituted by a first resistor and a second resistor is connected between the input pulse power supply and the N-channel MOSFET.

[0067] The present invention also provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in accordance with an input pulse voltage input from the input pulse power supply, wherein a pulse rise time adjustment circuit made up of an RC circuit formed by a first resistor and a capacitor is connected between the input pulse power supply and the N-channel MOSFET.

[0068] Furthermore, the present invention provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in accordance with an input pulse voltage input from the input pulse power supply, wherein a pulse width adjustment circuit made up of a resistance divider circuit formed by a first resistor and a second resistor is connected between the input pulse power supply and the N-channel MOSFET, and a pulse rise time adjustment circuit made up of an RC circuit formed by the first resistor and a capacitor is connected.

[0069] Furthermore, the present invention provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in response to an input pulse voltage input from the input pulse power supply, wherein a pulse fall time adjustment circuit composed of a third resistor and a charge power supply is connected to the drain of the N-channel MOSFET in such a way that the third resistor is connected in series between the charge power supply and the drain of the N-channel MOSFET.

[0070] Furthermore, the present invention provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in accordance with an input pulse voltage input from the input pulse power supply, wherein a pulse width adjustment circuit made up of a resistance divider circuit made up of a first resistor and a second resistor is connected between the input pulse power supply and the N-channel MOSFET, and a pulse fall time adjustment circuit made up of a third resistor and a charge power supply is connected to the drain of the N-channel MOSFET such that the third resistor is connected in series between the charge power supply and the drain of the N-channel MOSFET.

[0071] Furthermore, the present invention provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in response to an input pulse voltage input from the input pulse power supply, wherein a pulse rise time adjustment circuit made up of an RC circuit formed by a first resistor and a capacitor is connected between the input pulse power supply and the N-channel MOSFET, and a pulse fall time adjustment circuit made up of a third resistor and a charge power supply is connected to the drain of the N-channel MOSFET such that the third resistor is connected in series between the charge power supply and the drain of the N-channel MOSFET.

[0072] Furthermore, the present invention provides a pulse voltage conversion circuit having an input pulse power supply, an N-channel MOSFET driven by the input pulse power supply, a high-side switch driven by the N-channel MOSFET, and a high-side power supply connected to the high-side switch, and generating an output pulse voltage in response to an input pulse voltage input from the input pulse power supply, wherein a pulse width adjustment circuit consisting of a resistance divider circuit formed of a first resistor and a second resistor is connected between the input pulse power supply and the N-channel MOSFET, and a pulse rise time adjustment circuit consisting of an RC circuit formed of the first resistor and a capacitor is connected, and a pulse fall time adjustment circuit consisting of a third resistor and a charge power supply is connected to the drain of the N-channel MOSFET such that the third resistor is connected in series between the charge power supply and the drain of the N-channel MOSFET.

[0073] Furthermore, in the present invention, a first diode is connected between the third resistor and the drain of the N-channel MOSFET, and a second diode is connected between the high-side power supply and the drain of the N-channel MOSFET. [Effects of the Invention]

[0074] Since the present invention is configured as described above, it has the excellent effect of being able to provide a pulse voltage conversion circuit having a function of adjusting the pulse characteristics of an output pulse voltage (pulse characteristics adjustment function). [Brief explanation of the drawings]

[0075] [Figure 1] FIG. 1 is a circuit diagram of a conventional pulse voltage conversion circuit. [Figure 2]2(a), (b), (c), and (d) are timing charts showing the operation of pulse voltage conversion in the conventional pulse voltage conversion circuit shown in FIG. 1 when the threshold voltage of the N-channel MOSFET (Q1) is a reference value and the threshold voltage of the high-side switch (Q2) is a reference value. [Figure 3] 3(a'), (b'), (c'), and (d') are timing charts showing the operation of pulse voltage conversion in the conventional pulse voltage conversion circuit shown in FIG. 1 when the threshold voltage of the N-channel MOSFET (Q1) is higher than a reference value and the threshold voltage of the high-side switch (Q2) is lower than a reference value. [Figure 4] 4(a''), (b''), (c''), and (d'') are timing charts showing the operation of pulse voltage conversion in the conventional pulse voltage conversion circuit shown in FIG. 1 when the threshold voltage of the N-channel MOSFET (Q1) is lower than the reference value and the threshold voltage of the high-side switch (Q2) is higher than the reference value. [Figure 5] FIG. 5 is a circuit configuration diagram of a pulse voltage conversion circuit according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0076] Hereinafter, an example of an embodiment of a pulse voltage conversion circuit according to the present invention will be described in detail with reference to the accompanying drawings.

[0077] In the following description of the "Mode for Carrying Out the Invention" section, the same or corresponding configurations and functions as those described with reference to each of Figures 1 to 4 will be denoted by the same reference numerals as those used in each of Figures 1 to 4, and detailed description of those configurations and functions will be omitted.

[0078] FIG. 5 shows a circuit configuration diagram of a pulse voltage conversion circuit according to an embodiment of the present invention.

[0079] Comparing the pulse voltage conversion circuit 10 according to an embodiment of the present invention shown in FIG. 5 with a conventional pulse voltage conversion circuit 100, the two differ in that the pulse voltage conversion circuit 10 incorporates a pulse width adjustment circuit as a pulse characteristics adjustment circuit between the input pulse power supply 116, which is the signal source of the input pulse voltage Vin, and the gate (G) of the N-channel MOSFET (Q1) 118.

[0080] This pulse width adjustment circuit is configured by a resistor divider circuit made up of a resistor (Ra) 12 and a resistor (R1) 122.

[0081] Here, the resistor (Ra) 12 is connected in series to the input pulse power supply 116 and the gate (G) of the N-channel MOSFET (Q1) 118 on a connection line 120 that connects the input pulse power supply 116 and the gate (G) of the N-channel MOSFET (Q1) 118.

[0082] In this pulse voltage conversion circuit 10, too, a gate-source voltage Vgs is applied to an N-channel MOSFET (Q1) 118 in accordance with an input pulse voltage Vin. However, since an output impedance exists in the input pulse power supply 116, which is the signal source of the input pulse voltage Vin, and a gate terminal capacitance exists at the gate of the N-channel MOSFET (Q1) 118, the gate-source voltage Vgs has a waveform with a slope at the rise time and fall time.

[0083] Therefore, if the threshold voltage of the N-channel MOSFET (Q1) 118 fluctuates, the pulse width Tpw of the output pulse voltage Vout will change. However, since the pulse voltage conversion circuit 10 incorporates a pulse width adjustment circuit configured with a resistance divider circuit made up of resistors (Ra) 12 and (R1) 122, the peak value of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118 can be adjusted by changing (adjusting) the constants of the resistors (Ra) 12 and / or (R1) 122 of the resistance divider circuit that configures the pulse width adjustment circuit. As a result, the pulse width Tpw of the output pulse voltage Vout can be adjusted by controlling the time over which the threshold voltage of the N-channel MOSFET (Q1) 118 is exceeded and the time over which it is below the threshold voltage.

[0084] Furthermore, when the pulse voltage conversion circuit 10 is compared with the pulse voltage conversion circuit 100, the difference is that the pulse voltage conversion circuit 10 incorporates a pulse rise time adjustment circuit as a pulse characteristics adjustment circuit between the input pulse power supply 116, which is the signal source of the input pulse voltage Vin, and the gate (G) of the N-channel MOSFET (Q1) 118.

[0085] This pulse rise time adjustment circuit is composed of a resistor-capacitor circuit (RC circuit) consisting of a resistor (Ra) 12 and a capacitor (Ca) 14.

[0086] Here, the capacitor (Ca) 14 is connected to the connection line 120 between the resistor (Ra) 12 and the resistor (R1) 122, and is grounded to the ground.

[0087] The resistor (Ra) 12 is shared by the pulse rise time adjusting circuit and the pulse width adjusting circuit.

[0088] As explained above, the gate-source voltage Vgs has a slope in its rise time, which causes a corresponding rise time Ton in the output pulse voltage Vout.

[0089] This rise time Ton changes with fluctuations in the gate terminal capacitance of the N-channel MOSFET (Q1) 118. However, the pulse voltage conversion circuit 10 incorporates a pulse rise time adjustment circuit configured with a resistor-capacitor circuit (RC circuit) consisting of a resistor (Ra) 12 and a capacitor (Ca) 14. Therefore, by changing (adjusting) the constants of the resistor (Ra) 12 and / or the capacitor (Ca) 14 of the resistor-capacitor circuit (RC circuit) that configures the pulse rise time adjustment circuit, it is possible to adjust and control the rise time of the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118, and thereby adjust the pulse rise time Ton of the output pulse voltage Vout.

[0090] Furthermore, when comparing the pulse voltage conversion circuit 10 and the pulse voltage conversion circuit 100, the difference is that the pulse voltage conversion circuit 10 has a pulse fall time adjustment circuit provided as a pulse characteristics adjustment circuit at the drain (D) of the N-channel MOSFET (Q1) 118.

[0091] This pulse fall time adjustment circuit is composed of a resistor (Rb) 16 and a charge power supply (Va) 18.

[0092] Here, the resistor (Rb) 16 is connected in series between the charge power supply (Va) 18 and the drain (D) of the N-channel MOSFET (Q1) 118.

[0093] In the pulse voltage conversion circuit 10, even if conduction and disconnection between the drain and source of the N-channel MOSFET (Q1) 118 can be instantaneously performed, since the base-emitter voltage Vbe of the high-side switch (Q2) 106 is generated by a resistive divider circuit formed by the high-side power supply (V1) 104 and the resistors (R2) 124 and (R3) 130, the base terminal capacitance exists, so the fall time (negative voltage → 0 V) ​​of the base-emitter voltage Vbe of the high-side switch (Q2) 104 has a slope, and a corresponding fall time Toff occurs in the output pulse voltage Vout.

[0094] This fall time Toff changes with the drain-source conduction speed of the N-channel MOSFET (Q1) 118 (which depends on the gate-source voltage Vgs of the N-channel MOSFET (Q1) 118) and fluctuations in the base terminal capacitance of the high-side switch (Q2) 106. However, since the pulse voltage conversion circuit 10 incorporates a pulse fall time adjustment circuit constituted by the resistor (Rb) 16 and the charge power supply (Va) 18, by changing (adjusting) the constant of the resistor (Rb) 16 and / or the circuit constant of the charge power supply (Va) 18 that constitute the pulse fall time adjustment circuit, it is possible to adjust and control the fall time (negative voltage → 0 V) ​​of the base-emitter voltage Vbe of the high-side switch (Q2) 106, and thereby adjust the pulse fall time Toff of the output pulse voltage Vout.

[0095] Furthermore, when the pulse voltage conversion circuit 10 is compared with the pulse voltage conversion circuit 100, the two differ in that in the pulse voltage conversion circuit 10, even when the potential of the high side power supply (V1) 104 and the potential of the charge power supply (Va) 18 are not equal, a diode (Da) 20 is inserted and connected in series between the resistor (Rb) 16 and the drain of the N-channel MOSFET (Q1) 118 as a backflow prevention diode to prevent current from flowing back into the high side power supply (V1) 104 or the charge power supply (Va) 18, and a diode (Db) 22 is inserted and connected in series between the resistor (R2) and the drain of the N-channel MOSFET (Q1) 118, i.e., between the high side power supply (V1) 104 and the drain of the N-channel MOSFET (Q1) 118.

[0096] In the pulse voltage conversion circuit 10, when the output pulse voltage Vout is set to a desired peak value, the potential of the high-side power supply (V1) 104 is determined according to the desired peak value, but the potential of the charge power supply (Va) 18 described above cannot always be set to the same potential as that of the high-side power supply (V1).

[0097] Therefore, if the potential of the high side power supply (V1) 104 and the potential of the charge power supply (Va) 18 are different, current will flow backward from the higher potential to the lower potential when there is no conduction between the drain and source of the N-channel MOSFET (Q1) 118. However, since the diodes (Da) 20 and (Db) 22 are inserted in the pulse voltage conversion circuit 10, this backward current flow can be prevented, and it becomes possible to set the potential of the high side power supply (V1) 104 and the potential of the charge power supply (Va) 18 independently.

[0098] As described above, the pulse voltage conversion circuit 10 according to the present invention can adjust the pulse characteristics of the output pulse voltage by incorporating the above-described pulse width adjustment circuit into the conventional pulse voltage conversion circuit 100, or by incorporating the above-described pulse rise time adjustment circuit into the conventional pulse voltage conversion circuit 100, or by incorporating the above-described pulse fall time adjustment circuit into the conventional pulse voltage conversion circuit 100.

[0099] Furthermore, when the pulse voltage conversion circuit 10 according to the present invention is configured by incorporating the above-described pulse fall time adjustment circuit into the conventional pulse voltage conversion circuit 100, by incorporating a backflow prevention diode into the conventional pulse voltage conversion circuit 100, it becomes possible to prevent backflow of current to each power supply even when the potentials of the charge power supply and the high-side power supply are different.

[0100] Furthermore, the pulse voltage conversion circuit 10 according to the present invention is effective when a design change is made by replacing N-channel MOSFETs or high-side switches with alternative components due to reasons such as the discontinuation of production, and when it is desired to obtain pulse characteristics equivalent to those of the output pulse voltage in the circuit before the design change, or when it is desired to adjust the pulse characteristics of the output pulse voltage by changing the constants of the peripheral circuitry to prevent changes in the pulse characteristics of the output pulse voltage due to variations in the characteristics of each component during mass production.

[0101] It should be noted that the above-described embodiment is merely an example, and the present invention can be embodied in various other forms. In other words, the present invention is not limited to the above-described embodiment, and various omissions, substitutions, or modifications can be made as appropriate within the scope of the gist of the present invention.

[0102] For example, the above-described embodiment may be modified as described in (1) to (4) below.

[0103] (1) In the above-described embodiment, the pulse voltage conversion circuit according to the present invention is described as including a pulse width adjustment circuit, a pulse rise time adjustment circuit, a pulse fall time adjustment circuit, and a backflow prevention diode, but it is needless to say that the present invention is not limited to this.

[0104] That is, the pulse voltage conversion circuit according to the present invention may be provided with only a pulse width adjustment circuit, or only a pulse rise time adjustment circuit, or only a pulse fall time adjustment circuit, depending on design conditions, etc.

[0105] Alternatively, the pulse voltage conversion circuit according to the present invention may include only two circuits appropriately selected from the three circuits of the pulse width adjustment circuit, the pulse rise time adjustment circuit, and the pulse fall time adjustment circuit according to design conditions, etc.

[0106] Specifically, the pulse voltage conversion circuit according to the present invention may include only two circuits, a pulse width adjustment circuit and a pulse rise time adjustment circuit, or may include only two circuits, a pulse width adjustment circuit and a pulse fall time adjustment circuit, or may include only two circuits, a pulse rise time adjustment circuit and a pulse fall time adjustment circuit.

[0107] (2) In the above embodiment, the pulse voltage conversion circuit according to the present invention is described as being equipped with a backflow prevention diode, but it goes without saying that the present invention is not limited to this.

[0108] That is, the pulse voltage conversion circuit according to the present invention may not require the provision of a backflow prevention diode depending on design conditions and the like.

[0109] In particular, if the pulse voltage conversion circuit according to the present invention does not include a pulse fall time adjustment circuit, there is no need to provide a backflow prevention diode.

[0110] (3) In the above-described embodiment, detailed explanations of the constants of each component, including the pulse width adjustment circuit, pulse rise time adjustment circuit, pulse fall time adjustment circuit, and backflow prevention diode, have been omitted. However, these constants may be set appropriately depending on the design conditions, etc.

[0111] (4) It goes without saying that the above-described embodiment and the embodiments and modifications shown in (1) to (3) above may be combined as appropriate. [Industrial Applicability]

[0112] The present invention is extremely useful when used to convert an input pulse voltage into a pulse voltage (output pulse voltage) of a desired peak value, such as when converting a low-voltage pulse voltage (input pulse voltage) such as the output level of a TTL or CMOS into a high-voltage pulse voltage (output pulse voltage) of a desired peak value. [Explanation of symbols]

[0113] 10 Pulse voltage conversion circuit 12 Resistor (Ra) (first resistor) 14 Capacitor (Ca) 16 Resistor (Rb) (third resistor) 18 Charging power supply (Va) 20 Diode (Da) (first diode) 22 Diode (Db) (Second diode) 100 Pulse voltage conversion circuit 102 Current output terminal 104 High side power supply (V1) 106 High-side switch (Q2) 108 Resistor divider circuit 110 resistance (R4) 112 Resistor (R5) 114 connecting wire 116 Input pulse power supply 118 N-channel MOSFET(Q1) 120 connecting wire 122 Pull-down resistor (R1) (second resistor) 124 Resistance (R2) 126 Capacitor (C1) 128 connecting lines 130 resistance (R3)

Claims

1. a high-side switch that is driven by connecting a drain of the N-channel MOSFET to a control terminal; and a high-side power supply connected to supply power to the high-side switch, wherein the pulse voltage conversion circuit generates an output pulse voltage that is output from an output terminal of the high-side switch in response to an input pulse voltage input from the input pulse power supply, Between the input pulse power supply and the N-channel MOSFET, a pulse rise time adjustment circuit is connected, the pulse rise time adjustment circuit being composed of an RC circuit in which one end of a first resistor is connected to the input pulse power supply, the other end of the first resistor and one end of a capacitor are connected to the gate of the N-channel MOSFET, and the other end of the capacitor is connected to the source of the N-channel MOSFET. A pulse voltage conversion circuit comprising:

2. a high-side switch that is driven by connecting a drain of the N-channel MOSFET to a control terminal; and a high-side power supply connected to supply power to the high-side switch, wherein the pulse voltage conversion circuit generates an output pulse voltage that is output from an output terminal of the high-side switch in response to an input pulse voltage input from the input pulse power supply, Between the input pulse power supply and the N-channel MOSFET, a pulse width adjustment circuit is connected, which is made up of a resistive divider circuit, one end of which is connected to the input pulse power supply, the other end of which is connected to one end of a second resistor and the gate of the N-channel MOSFET, and the other end of which is connected to the source of the N-channel MOSFET; and a pulse rise time adjustment circuit is connected, which is made up of an RC circuit, one end of which is connected to the input pulse power supply, the other end of which is connected to one end of a capacitor and the gate of the N-channel MOSFET, and the other end of which is connected to the source of the N-channel MOSFET. A pulse voltage conversion circuit comprising:

3. a high-side switch that is driven by connecting a drain of the N-channel MOSFET to a control terminal; and a high-side power supply connected to supply power to the high-side switch, wherein the pulse voltage conversion circuit generates an output pulse voltage that is output from an output terminal of the high-side switch in response to an input pulse voltage input from the input pulse power supply, Between the input pulse power supply and the N-channel MOSFET, a pulse rise time adjustment circuit is connected, the pulse fall time adjustment circuit being composed of an RC circuit, one end of a first resistor being connected to the input pulse power supply, the other end of the first resistor and one end of a capacitor being connected to the gate of the N-channel MOSFET, and the other end of the capacitor being connected to the source of the N-channel MOSFET; and to the drain of the N-channel MOSFET, a pulse fall time adjustment circuit being composed of a third resistor and a charge power supply is connected in series between the charge power supply and the drain of the N-channel MOSFET. A pulse voltage conversion circuit comprising:

4. a high-side switch that is driven by connecting a drain of the N-channel MOSFET to a control terminal; and a high-side power supply connected to supply power to the high-side switch, wherein the pulse voltage conversion circuit generates an output pulse voltage that is output from an output terminal of the high-side switch in response to an input pulse voltage input from the input pulse power supply, a pulse width adjustment circuit is connected between the input pulse power supply and the N-channel MOSFET, the pulse width adjustment circuit being made up of a resistive divider circuit, one end of which is connected to the input pulse power supply, the other end of which is connected to one end of a second resistor and the gate of the N-channel MOSFET, and the other end of which is connected to the source of the N-channel MOSFET; and a pulse rise time adjustment circuit is connected between the input pulse power supply and the N-channel MOSFET, the other end of which is connected to one end of the first resistor and the gate of the N-channel MOSFET, the other end of which is connected to one end of a capacitor and the source of the N-channel MOSFET, A pulse fall time adjustment circuit composed of a third resistor and a charge power supply is connected to the drain of the N-channel MOSFET in such a manner that the third resistor is connected in series between the charge power supply and the drain of the N-channel MOSFET. A pulse voltage conversion circuit comprising:

5. 5. The pulse voltage conversion circuit according to claim 3, further comprising: a first diode is connected between the third resistor and the drain of the N-channel MOSFET; A second diode is connected between the high-side power supply and the drain of the N-channel MOSFET. A pulse voltage conversion circuit comprising:

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