A voltage regulating circuit and ultrasonic equipment

Abstract

The present invention discloses a voltage regulating circuit, including a DC-DC conversion circuit, a positive linear voltage regulator, a negative linear voltage regulator and a voltage difference control circuit. The voltage regulating circuit of the present application adds a positive linear voltage regulator and a negative linear voltage regulator on the basis of the DC-DC conversion circuit, which can suppress the interference signal in the output voltage of the DC-DC conversion circuit to provide a stable power supply for the transmitting chip in the ultrasonic device, thereby improving the imaging effect of the ultrasonic device. Moreover, considering that the greater the input-output voltage difference of the positive linear voltage regulator and the negative linear voltage regulator, the greater the power consumption of the two, the present application also adds a voltage difference control circuit, which can adjust the input-output voltage difference of the positive linear voltage regulator and the negative linear voltage regulator, thereby avoiding damage to the two due to excessive power consumption. The present invention also discloses an ultrasonic device, which has the same beneficial effects as the above-mentioned voltage regulating circuit.

Description

Technical Field

[0001] The present invention relates to the field of disease diagnosis, and in particular to a voltage regulating circuit and ultrasonic equipment. Background Art

[0002] Ultrasonic equipment is widely used in the field of disease diagnosis. Its working principle is: transmitting ultrasonic signals to the human body and receiving ultrasonic echo signals, so as to use ultrasonic echo imaging technology to examine human diseases. At present, ultrasonic equipment can work in different modes. When the ultrasonic equipment works in different modes, the power supply voltage required by its transmitting chip is different. In the prior art, the power supply voltage of the transmitting chip is adjusted by using a DC-DC conversion circuit to provide the corresponding power supply voltage for the transmitting chip in different modes. However, the output voltage of the DC-DC conversion circuit contains a large interference signal, which will affect the imaging effect of the ultrasonic equipment.

[0003] Therefore, how to provide a solution to the above technical problems is a problem that technicians in this field need to solve at present. Summary of the invention

[0004] The purpose of the present invention is to provide a voltage regulating circuit and an ultrasonic device, which can suppress interference signals in the output voltage of a DC-DC conversion circuit to provide a stable power supply for a transmitting chip in the ultrasonic device, thereby improving the imaging effect of the ultrasonic device; moreover, the input and output voltage difference of a positive linear regulator and a negative linear regulator can be adjusted to avoid damage to the two due to excessive power consumption.

[0005] In order to solve the above technical problems, the present invention provides a voltage regulating circuit, which is applied to an ultrasound device including a transmitting chip, comprising:

[0006] A DC-DC conversion circuit having an input end connected to a DC power supply;

[0007] A positive linear regulator having an input end connected to the positive output end of the DC-DC conversion circuit and an output end connected to the positive power supply end of the transmitting chip;

[0008] A negative linear regulator having an input end connected to the negative output end of the DC-DC conversion circuit and an output end connected to the negative power supply end of the transmitting chip;

[0009] The voltage difference control circuits respectively connected to the DC-DC conversion circuit, the positive linear regulator and the negative linear regulator are used to control the output voltages of the positive linear regulator and the negative linear regulator according to the power supply requirements of the transmitting chip; the voltage difference control circuit is also used to control the input and output voltage differences of the positive linear regulator and the negative linear regulator by adjusting the output voltage of the DC-DC conversion circuit.

[0010] Preferably, the voltage difference control circuit includes:

[0011] A D / A converter connected to the reference terminal of the positive linear regulator and the reference terminal of the negative linear regulator, respectively, for controlling the output voltage of the positive linear regulator and the negative linear regulator by adjusting its own output voltage;

[0012] A voltage difference circuit connected to the output terminal of the D / A converter, used for making a difference between the output voltage of the D / A converter and the adjustable negative bias voltage, and using the difference between the two as a given value of the DC-DC conversion circuit;

[0013] A voltage feedback circuit connected to the output end of the voltage difference circuit and the DC-DC conversion circuit respectively is used to control the positive output voltage of the DC-DC conversion circuit to track a voltage value that is in a certain proportion to the given value; wherein the negative output voltage of the DC-DC conversion circuit and its positive output voltage are inverse numbers of each other.

[0014] Preferably, the voltage difference circuit comprises a first resistor, a second resistor and a first operational amplifier; wherein:

[0015] The positive input terminal of the first operational amplifier is connected to the output terminal of the D / A converter, the negative input terminal of the first operational amplifier is respectively connected to the first end of the first resistor and the first end of the second resistor, the second end of the first resistor is connected to an adjustable negative bias voltage, the second end of the second resistor is connected to the output terminal of the first operational amplifier and the common end serves as the output terminal of the voltage difference circuit; wherein the resistance values ​​of the first resistor and the second resistor are equal.

[0016] Preferably, the voltage difference circuit further includes a third resistor and a fourth resistor; wherein:

[0017] The first end of the third resistor is connected to the output end of the D / A converter, the second end of the third resistor is connected to the positive input end of the first operational amplifier and the first end of the fourth resistor respectively, and the second end of the fourth resistor is grounded;

[0018] The voltage difference circuit is further used to match the impedance of the positive input terminal and the negative input terminal of the first operational amplifier by adjusting the resistance values ​​of the third resistor and the fourth resistor.

[0019] Preferably, the voltage difference circuit further includes:

[0020] a first capacitor connected in parallel with the second resistor;

[0021] A second capacitor connected in parallel with the fourth resistor.

[0022] Preferably, the voltage feedback circuit comprises a fifth resistor, a sixth resistor, a seventh resistor, a third capacitor, a fourth capacitor and a second operational amplifier; wherein:

[0023] The positive input terminal of the second operational amplifier is connected to the output terminal of the voltage difference circuit, the negative input terminal of the second operational amplifier is respectively connected to the first end of the fifth resistor, the first end of the sixth resistor, the first end of the third capacitor and the first end of the fourth capacitor, the second end of the fifth resistor is connected to the positive output terminal of the DC-DC conversion circuit, the second end of the sixth resistor is grounded, the second end of the third capacitor is connected to the first end of the seventh resistor, and the second end of the seventh resistor is respectively connected to the second end of the fourth capacitor, the output terminal of the second operational amplifier and the comparison terminal of the DC-DC conversion circuit;

[0024] The voltage feedback circuit is specifically used to control the DC-DC conversion circuit to adjust its output voltage so that the voltage value of the negative input terminal of the second operational amplifier tracks the voltage value of the positive input terminal thereof.

[0025] Preferably, the DC-DC conversion circuit includes a DC-DC controller, a switch tube, a sampling resistor, a transformer, a first rectifier diode and a second rectifier diode; wherein:

[0026] The comparison end of the DC-DC controller is connected to the output end of the voltage feedback circuit, the detection end of the DC-DC controller is connected to the first end of the sampling resistor, the second end of the sampling resistor is grounded, the driving end of the DC-DC controller is connected to the control end of the switch tube, the first end of the switch tube is connected to the input negative end of the transformer, the input positive end of the transformer is connected to the power supply end of the DC-DC controller and the common end is connected to the DC power supply, the output positive end of the transformer is connected to the anode of the first rectifier diode, the cathode of the first rectifier diode serves as the output positive end of the DC-DC conversion circuit, the output negative end of the transformer is connected to the cathode of the second rectifier diode, the anode of the second rectifier diode serves as the output negative end of the DC-DC conversion circuit, and the middle tap of the transformer is grounded;

[0027] The DC-DC conversion circuit is specifically used to adjust the duty cycle of the driving pulse of the switch tube according to the comparison result of the voltage inputted between its comparison terminal and the detection terminal, so as to adjust its output voltage.

[0028] Preferably, the DC-DC conversion circuit further includes a fifth capacitor and a sixth capacitor; wherein:

[0029] The first end of the fifth capacitor is connected to the cathode of the first rectifier diode, the first end of the sixth capacitor is connected to the anode of the second rectifier diode, the second end of the fifth capacitor is connected to the second end of the sixth capacitor and the common end is grounded.

[0030] Preferably, the positive output voltage of the DC-DC conversion circuit / (the output voltage of the D / A converter-the negative bias voltage)=the output voltage of the positive linear regulator / the output voltage of the D / A converter;

[0031] Negative output voltage of the DC-DC conversion circuit / (output voltage of the D / A converter-negative bias voltage)=output voltage of the negative linear regulator / output voltage of the D / A converter.

[0032] In order to solve the above technical problems, the present invention further provides an ultrasonic device, comprising a transmitting chip and any one of the above voltage regulating circuits.

[0033] The present invention provides a voltage regulating circuit, including a DC-DC conversion circuit, a positive linear voltage regulator, a negative linear voltage regulator and a voltage difference control circuit. The voltage regulating circuit of the present application adds a positive linear voltage regulator and a negative linear voltage regulator on the basis of the DC-DC conversion circuit, which can suppress the interference signal in the output voltage of the DC-DC conversion circuit to provide a stable power supply for the transmitting chip in the ultrasound equipment, thereby improving the imaging effect of the ultrasound equipment. Moreover, considering that the greater the input-output voltage difference of the positive linear voltage regulator and the negative linear voltage regulator, the greater the power consumption of the two, the present application also adds a voltage difference control circuit, which can adjust the input-output voltage difference of the positive linear voltage regulator and the negative linear voltage regulator, thereby avoiding damage to the two due to excessive power consumption.

[0034] The present invention also provides an ultrasonic device having the same beneficial effects as the above voltage regulating circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 A schematic diagram of the structure of a voltage regulation circuit provided by an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of a specific structure of a voltage regulation circuit provided by an embodiment of the present invention;

[0038] Figure 3A schematic diagram of a circuit for generating a negative bias voltage provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The core of the present invention is to provide a voltage regulation circuit and an ultrasonic device, which can suppress the interference signal in the output voltage of the DC-DC conversion circuit to provide a stable power supply for the transmitting chip in the ultrasonic device, thereby improving the imaging effect of the ultrasonic device; moreover, the input and output voltage difference of the positive linear regulator and the negative linear regulator can be adjusted to avoid damage to the two due to excessive power consumption.

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a voltage regulation circuit provided by an embodiment of the present invention.

[0042] The voltage regulating circuit is applied to an ultrasound device including a transmitting chip, including:

[0043] A DC-DC conversion circuit 1 having an input terminal connected to a DC power supply;

[0044] A positive linear regulator 2 having an input end connected to the positive output end of the DC-DC conversion circuit 1 and an output end connected to the positive power supply end of the transmitting chip;

[0045] A negative linear regulator 3 having an input end connected to the negative output end of the DC-DC conversion circuit 1 and an output end connected to the negative power supply end of the transmitting chip;

[0046] The voltage difference control circuit 4, which is respectively connected to the DC-DC conversion circuit 1, the positive linear regulator 2 and the negative linear regulator 3, is used to control the output voltage of the positive linear regulator 2 and the negative linear regulator 3 according to the power supply requirement of the transmitting chip; the voltage difference control circuit 4 is also used to control the input and output voltage difference of the positive linear regulator 2 and the negative linear regulator 3 by adjusting the output voltage of the DC-DC conversion circuit 1.

[0047] Specifically, the voltage regulation circuit of the present application includes a DC-DC conversion circuit 1, a positive linear regulator 2, a negative linear regulator 3 and a voltage difference control circuit 4, and its working principle is:

[0048] The DC-DC conversion circuit 1 is used to convert the DC voltage input by the DC power supply and output another DC voltage. The DC voltage output by the DC-DC conversion circuit 1 includes a positive DC voltage and a negative DC voltage. The positive DC voltage is input to the positive linear regulator 2, and the negative DC voltage is input to the negative linear regulator 3. The output voltages of the positive linear regulator 2 and the negative linear regulator 3 are controlled by the voltage difference control circuit 4, the purpose of which is to make the output voltages of the positive linear regulator 2 and the negative linear regulator 3 meet the power supply requirements of the transmitting chip. The positive linear regulator 2 and the negative linear regulator 3 are specifically used to convert the input DC voltage into the power supply voltage required by the transmitting chip. Since the positive linear regulator 2 and the negative linear regulator 3 have voltage stabilization performance, they can suppress interference signals in the output voltage of the DC-DC conversion circuit 1 (for example, the voltage signal fluctuation output by the DC-DC conversion circuit 1 will produce ripple noise, which interferes with the voltage signal, and the front-end hardware inside the positive linear regulator 2 and the negative linear regulator 3 includes a filtering and voltage stabilizing device for suppressing interference signals such as ripple noise, which can effectively suppress interference signals such as ripple noise in the voltage signal), so the present application can provide a stable power supply voltage for the transmitting chip, thereby improving the imaging effect of the ultrasound equipment.

[0049] Considering that the greater the input-output voltage difference between the positive linear regulator 2 and the negative linear regulator 3, the greater the power consumption of the two, the voltage difference control circuit 4 of the present application can also adjust the input-output voltage difference between the positive linear regulator 2 and the negative linear regulator 3 to adjust the power consumption of the two. Specifically, since the voltage difference control circuit 4 can control the output voltage of the positive linear regulator 2 and the negative linear regulator 3, the voltage difference control circuit 4 controls the input voltage of the positive linear regulator 2 and the negative linear regulator 3, that is, the output voltage of the DC-DC conversion circuit 1, and the input-output voltage difference of the positive linear regulator 2 and the negative linear regulator 3 can be controlled, thereby preventing the two from being damaged due to excessive power consumption.

[0050] More specifically, the positive linear regulator 2 and the negative linear regulator 3 of the present application may use LDO (Low Dropout Regulator), which has the advantages of low cost and small output ripple.

[0051] Please refer to Figure 2 , Figure 2 A specific structural diagram of a voltage regulating circuit provided in an embodiment of the present invention. The voltage regulating circuit is based on the above embodiment:

[0052] As an optional embodiment, the voltage difference control circuit 4 includes:

[0053] A D / A converter 41 connected to the reference terminal of the positive linear regulator 2 and the reference terminal of the negative linear regulator 3, respectively, for controlling the output voltages of the positive linear regulator 2 and the negative linear regulator 3 by adjusting its own output voltage;

[0054] A voltage difference circuit 42 connected to the output terminal of the D / A converter 41 is used to make a difference between the output voltage of the D / A converter 41 and the adjustable negative bias voltage, and use the difference between the two as a given value of the DC-DC conversion circuit 1;

[0055] The voltage feedback circuit 43 connected to the output end of the voltage difference circuit 42 and the DC-DC conversion circuit 1 respectively is used to control the positive output voltage of the DC-DC conversion circuit 1 to track a voltage value that is in a certain proportion to a given value; wherein the negative output voltage of the DC-DC conversion circuit 1 and its positive output voltage are inverse numbers of each other.

[0056] Specifically, the voltage difference control circuit 4 of the present application includes a D / A converter 41, a voltage difference circuit 42 and a voltage feedback circuit 43, and its working principle is:

[0057] The D / A converter 41 is used to convert the received digital signal into an analog voltage signal, and input the analog voltage signal to the reference terminal (VREF1) of the positive linear regulator 2 and the reference terminal (VREF2) of the negative linear regulator 3. Figure 2 It can be seen that the output end of the positive linear regulator 2 is connected to a voltage divider circuit composed of resistors R8 and R9, and the output voltage of this voltage divider circuit is fed back to the feedback end (FB1) of the positive linear regulator 2. It is known that the output voltage of the positive linear regulator = (R8 / R9+1)*VREF1, so when the resistance values ​​of resistors R8 and R9 are selected, the present application can control the output voltage of the positive linear regulator 2 by adjusting the output voltage of the D / A converter 41. Similarly, the output end of the negative linear regulator 3 is connected to a voltage divider circuit composed of resistors R10 and R11, and the output voltage of this voltage divider circuit is fed back to the feedback end (FB2) of the negative linear regulator 3. It is known that the output voltage of the negative linear regulator = -(R10 / R11)*VREF2, so when the resistance values ​​of resistors R10 and R11 are selected, the present application can control the output voltage of the negative linear regulator 3 by adjusting the output voltage of the D / A converter 41.

[0058] The analog voltage signal output by the D / A converter 41 is also input to the voltage difference circuit 42. The voltage difference circuit 42 is also input with a negative bias voltage whose voltage value is adjustable. The voltage difference circuit 42 is used to subtract the negative bias voltage from the input analog voltage signal, that is, to add the absolute value of the negative bias voltage to the input analog voltage signal, and input the difference between the two to the voltage feedback circuit 43. The voltage feedback circuit 43 is used to control the positive output voltage of the DC-DC conversion circuit 1 to track a voltage value that is proportional to the difference voltage output by the voltage difference circuit 42. When the positive output voltage of the DC-DC conversion circuit 1 changes, the negative output voltage of the DC-DC conversion circuit 1 changes accordingly. Specifically, the negative output voltage of the DC-DC conversion circuit 1 = - the positive output voltage of the DC-DC conversion circuit 1, thereby adjusting the output voltage of the DC-DC conversion circuit 1.

[0059] It should be noted that, since the output voltages of the positive linear regulator 2 and the negative linear regulator 3 are less than their respective input voltages, the adjustable bias voltage should be set to a negative value, i.e., a negative bias voltage. More specifically, the negative bias voltage can be provided by a reverse proportional amplifier circuit, such as Figure 3 As shown, the reverse proportional amplifier circuit includes resistors R12-R16, capacitors C10-C11 and operational amplifier U4. The reverse proportional amplifier circuit inputs a positive voltage Vbiasin and outputs a negative bias voltage Vbiasout, thereby adjusting the output negative bias voltage Vbiasout by adjusting the input positive voltage Vbiasin.

[0060] As an optional embodiment, the voltage difference circuit 42 includes a first resistor R1, a second resistor R2 and a first operational amplifier U1; wherein:

[0061] The positive input terminal of the first operational amplifier U1 is connected to the output terminal of the D / A converter 41, the negative input terminal of the first operational amplifier U1 is respectively connected to the first end of the first resistor R1 and the first end of the second resistor R2, the second end of the first resistor R1 is connected to an adjustable negative bias voltage, the second end of the second resistor R2 is connected to the output terminal of the first operational amplifier U1 and the common end serves as the output terminal of the voltage difference circuit 42; wherein, the resistance values ​​of the first resistor R1 and the second resistor R2 are equal.

[0062] Specifically, the voltage difference circuit 42 of the present application includes a first resistor R1, a second resistor R2 and a first operational amplifier U1, and its working principle is:

[0063] It is known that the output voltage of the first operational amplifier = (analog voltage output by the D / A converter - negative bias voltage) * R2 / R1. Based on the principle of the voltage difference circuit 42: the input analog voltage signal is subtracted from the negative bias voltage to obtain the difference between the two, it can be obtained that the resistance values ​​of the first resistor R1 and the second resistor R2 should be equal.

[0064] As an optional embodiment, the voltage difference circuit 42 further includes a third resistor R3 and a fourth resistor R4; wherein:

[0065] A first end of the third resistor R3 is connected to the output end of the D / A converter 41, a second end of the third resistor R3 is connected to the positive input end of the first operational amplifier U1 and a first end of the fourth resistor R4 respectively, and a second end of the fourth resistor R4 is grounded;

[0066] The voltage difference circuit 42 is further used to match the impedance of the positive input terminal and the negative input terminal of the first operational amplifier U1 by adjusting the resistance values ​​of the third resistor R3 and the fourth resistor R4.

[0067] Furthermore, the voltage difference circuit 42 of the present application further includes a third resistor R3 and a fourth resistor R4, and its working principle is:

[0068] Considering that the output of the first operational amplifier U1 will be more stable when the impedances at the positive input terminal and the negative input terminal are matched, the present application adds a third resistor R3 and a fourth resistor R4 to the positive input terminal of the first operational amplifier U1, and by adjusting the resistance values ​​of the third resistor R3 and the fourth resistor R4, the impedances of the positive input terminal and the negative input terminal of the first operational amplifier U1 are matched, that is, the impedance of the positive input terminal of the first operational amplifier U1 = the impedance of its negative input terminal.

[0069] As an optional embodiment, the voltage difference circuit 42 further includes:

[0070] A first capacitor C1 connected in parallel with the second resistor R2;

[0071] A second capacitor C2 is connected in parallel with the fourth resistor R4.

[0072] Furthermore, the voltage difference circuit 42 of the present application further includes a first capacitor C1 and a second capacitor C2, and its working principle is as follows:

[0073] The first capacitor C1 and the second capacitor C2 are both used to prevent signal oscillation in the circuit to stabilize the output of the first operational amplifier U1.

[0074] In addition, from Figure 2 It can be seen that the +5V power supply terminal and the -5V power supply terminal of the first operational amplifier U1 are respectively connected to capacitors C7 and C8, and both capacitors C7 and C8 play a filtering role to stabilize the power supply of the first operational amplifier U1.

[0075] As an optional embodiment, the voltage feedback circuit 43 includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a third capacitor C3, a fourth capacitor C4 and a second operational amplifier U2; wherein:

[0076] The positive input terminal of the second operational amplifier U2 is connected to the output terminal of the voltage difference circuit 42, the negative input terminal of the second operational amplifier U2 is respectively connected to the first end of the fifth resistor R5, the first end of the sixth resistor R6, the first end of the third capacitor C3 and the first end of the fourth capacitor C4, the second end of the fifth resistor R5 is connected to the positive output terminal of the DC-DC conversion circuit 1, the second end of the sixth resistor R6 is grounded, the second end of the third capacitor C3 is connected to the first end of the seventh resistor R7, and the second end of the seventh resistor R7 is respectively connected to the second end of the fourth capacitor C4, the output terminal of the second operational amplifier U2 and the comparison terminal of the DC-DC conversion circuit 1;

[0077] The voltage feedback circuit 43 is specifically used to control the DC-DC conversion circuit 1 to adjust its output voltage so that the voltage value of the negative input terminal of the second operational amplifier U2 tracks the voltage value of the positive input terminal thereof.

[0078] Specifically, the voltage feedback circuit 43 of the present application includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a third capacitor C3, a fourth capacitor C4 and a second operational amplifier U2, and its working principle is:

[0079] The input voltage of the negative input terminal of the second operational amplifier = [R6 / (R5+R6)] * the positive output voltage of the DC-DC conversion circuit, and the input voltage of the positive input terminal of the second operational amplifier = the difference voltage output by the voltage difference circuit. The voltage feedback circuit 43 is used to control the DC-DC conversion circuit 1 to adjust its output voltage so that the voltage value of the negative input terminal of the second operational amplifier U2 tracks the voltage value of its positive input terminal, that is, to control the positive output voltage of the DC-DC conversion circuit to track a voltage value that is proportional to the difference voltage output by the voltage difference circuit 42, specifically, the positive output voltage of the DC-DC conversion circuit = the difference voltage output by the voltage difference circuit * (R5 / R6+1).

[0080] The seventh resistor R7, the third capacitor C3 and the fourth capacitor C4 are used to provide a certain amplitude margin and phase margin for the second operational amplifier U2, so as to improve the stability of the loop.

[0081] As an optional embodiment, the DC-DC conversion circuit 1 includes a DC-DC controller U3, a switch tube Q, a sampling resistor Rs, a transformer T, a first rectifier diode D1 and a second rectifier diode D2; wherein:

[0082] The comparison end of the DC-DC controller U3 is connected to the output end of the voltage feedback circuit 43, the detection end of the DC-DC controller U3 is connected to the first end of the sampling resistor Rs, the second end of the sampling resistor Rs is grounded, the driving end of the DC-DC controller U3 is connected to the control end of the switch tube Q, the first end of the switch tube Q is connected to the input negative end of the transformer T, the input positive end of the transformer T is connected to the power supply end of the DC-DC controller U3 and the common end is connected to the DC power supply, the output positive end of the transformer T is connected to the anode of the first rectifier diode D1, the cathode of the first rectifier diode D1 serves as the output positive end of the DC-DC conversion circuit 1, the output negative end of the transformer T is connected to the cathode of the second rectifier diode D2, the anode of the second rectifier diode D2 serves as the output negative end of the DC-DC conversion circuit 1, and the middle tap of the transformer T is grounded;

[0083] The DC-DC conversion circuit 1 is specifically used to adjust the duty cycle of the driving pulse of the switch tube Q according to the comparison result of the voltage inputted between its comparison terminal and the detection terminal, so as to adjust its output voltage.

[0084] Specifically, the DC-DC conversion circuit 1 of the present application includes a DC-DC controller U3, a switch tube Q, a sampling resistor Rs, a transformer T, a first rectifier diode D1 and a second rectifier diode D2, and its working principle is:

[0085] The voltage input to the comparison terminal (COMP) of the DC-DC controller U3 is the output voltage of the voltage feedback circuit 43, and the voltage input to the detection terminal (SENSE) of the DC-DC controller U3 is the voltage signal across the sampling resistor Rs. The DC-DC controller U3 is used to adjust the duty cycle of the drive pulse of the switch tube Q according to the comparison result of the voltage input to its own comparison terminal and the detection terminal. It is known that the on-time of the switch tube Q depends on the duty cycle of its drive pulse, so when the duty cycle of the drive pulse of the switch tube Q changes, the on-time of the switch tube Q also changes accordingly. When the on-time of the switch tube Q changes, the output voltage of the DC-DC conversion circuit 1 changes accordingly, thereby playing a role in adjusting the output voltage of the DC-DC conversion circuit 1.

[0086] More specifically, the switch tube Q of the present application can be an NMOS tube, the gate of the NMOS tube serves as the control end of the switch tube Q, the drain of the NMOS tube serves as the first end of the switch tube Q, and the source of the NMOS tube serves as the second end of the switch tube Q. In addition, a capacitor C9 is provided at the output end of the DC power supply to stabilize the output voltage VIN of the DC power supply.

[0087] As an optional embodiment, the DC-DC conversion circuit 1 further includes a fifth capacitor C5 and a sixth capacitor C6; wherein:

[0088] A first end of the fifth capacitor C5 is connected to the cathode of the first rectifier diode D1 , a first end of the sixth capacitor C6 is connected to the anode of the second rectifier diode D2 , a second end of the fifth capacitor C5 is connected to the second end of the sixth capacitor C6 and a common end is grounded.

[0089] Furthermore, the DC-DC conversion circuit 1 of the present application further includes a fifth capacitor C5 and a sixth capacitor C6, and its working principle is as follows:

[0090] The fifth capacitor C5 and the sixth capacitor C6 play a filtering role, thereby stabilizing the output voltage of the DC-DC conversion circuit 1 .

[0091] As an optional embodiment, the positive output voltage of the DC-DC conversion circuit / (the output voltage of the D / A converter-the negative bias voltage)=the output voltage of the positive linear regulator / the output voltage of the D / A converter;

[0092] Negative output voltage of the DC-DC conversion circuit / (output voltage of the D / A converter-negative bias voltage)=output voltage of the negative linear regulator / output voltage of the D / A converter.

[0093] Specifically, it is known that the positive output voltage of the DC-DC conversion circuit = the input voltage of the negative input terminal of the second operational amplifier * (R5 / R6+1), the input voltage of the positive input terminal of the second operational amplifier = the difference voltage output by the voltage difference circuit = the output voltage of the D / A converter - the negative bias voltage. Since the voltage value of the negative input terminal of the second operational amplifier tracks the voltage value of its positive input terminal, the positive output voltage of the DC-DC conversion circuit = (the output voltage of the D / A converter - the negative bias voltage) * (R5 / R6+1).

[0094] It is known that the output voltage of the positive linear regulator = (R8 / R9+1)*output voltage of the D / A converter. The present application sets: positive output voltage of the DC-DC converter circuit / (output voltage of the D / A converter-negative bias voltage) = output voltage of the positive linear regulator / output voltage of the D / A converter, so R5 / R6 = R8 / R9. Based on this, when the output voltage of the D / A converter is constant, the output voltage of the positive linear regulator is also a constant value, and the voltage difference between the positive output voltage of the DC-DC converter circuit and the output voltage of the positive linear regulator depends on the magnitude of the negative bias voltage, that is, the input-output voltage difference of the positive linear regulator can be set by setting the negative bias voltage.

[0095] Similarly, it is known that the negative output voltage of the DC-DC conversion circuit = the inverse of the positive output voltage of the DC-DC conversion circuit, so the negative output voltage of the DC-DC conversion circuit = -(output voltage of the D / A converter - negative bias voltage)*(R5 / R6+1).

[0096] It is known that the output voltage of the negative linear regulator = -(R10 / R11)*output voltage of the D / A converter, and the present application sets: negative output voltage of the DC-DC converter circuit / (output voltage of the D / A converter - negative bias voltage) = output voltage of the negative linear regulator / output voltage of the D / A converter, so R10 / R11 = (R8 / R9) + 1. Based on this, when the output voltage of the D / A converter is constant, the output voltage of the negative linear regulator is also a constant value, and the voltage difference between the negative output voltage of the DC-DC converter circuit and the output voltage of the negative linear regulator depends on the magnitude of the negative bias voltage, that is, the input-output voltage difference of the negative linear regulator can be set by setting the negative bias voltage.

[0097] The present application also provides an ultrasonic device, including a transmitting chip and any of the above voltage regulating circuits. It should be noted that the transmitting chip of the present application can be used to implement ultrasonic excitation signals, which can be a conventional transmitting chip, such as MAX14808 and other models, which will not be described in detail here.

[0098] For an introduction to the ultrasonic device provided in this application, please refer to the above-mentioned embodiment of the voltage regulation circuit, and this application will not go into details here.

[0099] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0100] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A voltage regulating circuit, characterized in that: Applicable to ultrasound equipment containing transmitter chips, including: A DC-DC conversion circuit having an input end connected to a DC power supply; A positive linear regulator having an input end connected to the positive output end of the DC-DC conversion circuit and an output end connected to the positive power supply end of the transmitting chip; A negative linear regulator having an input end connected to the negative output end of the DC-DC conversion circuit and an output end connected to the negative power supply end of the transmitting chip; A voltage difference control circuit connected to the DC-DC conversion circuit, the positive linear regulator and the negative linear regulator respectively, used to control the output voltage of the positive linear regulator and the negative linear regulator according to the power supply requirement of the transmitting chip; the voltage difference control circuit is also used to control the input and output voltage difference of the positive linear regulator and the negative linear regulator by adjusting the output voltage of the DC-DC conversion circuit; Wherein, the voltage difference control circuit includes: A D / A converter connected to the reference terminal of the positive linear regulator and the reference terminal of the negative linear regulator, respectively, for controlling the output voltage of the positive linear regulator and the negative linear regulator by adjusting its own output voltage; A voltage difference circuit connected to the output terminal of the D / A converter, used for making a difference between the output voltage of the D / A converter and the adjustable negative bias voltage, and using the difference between the two as a given value of the DC-DC conversion circuit; A voltage feedback circuit connected to the output end of the voltage difference circuit and the DC-DC conversion circuit respectively is used to control the positive output voltage of the DC-DC conversion circuit to track a voltage value that is in a certain proportion to the given value; wherein the negative output voltage of the DC-DC conversion circuit and its positive output voltage are inverse numbers of each other.

2. The voltage regulating circuit according to claim 1, characterized in that: The voltage difference circuit includes a first resistor, a second resistor and a first operational amplifier; wherein: The positive input terminal of the first operational amplifier is connected to the output terminal of the D / A converter, the negative input terminal of the first operational amplifier is respectively connected to the first end of the first resistor and the first end of the second resistor, the second end of the first resistor is connected to an adjustable negative bias voltage, the second end of the second resistor is connected to the output terminal of the first operational amplifier and the common end serves as the output terminal of the voltage difference circuit; wherein the resistance values ​​of the first resistor and the second resistor are equal.

3. The voltage regulating circuit according to claim 2, characterized in that: The voltage difference circuit further includes a third resistor and a fourth resistor; wherein: The first end of the third resistor is connected to the output end of the D / A converter, the second end of the third resistor is connected to the positive input end of the first operational amplifier and the first end of the fourth resistor respectively, and the second end of the fourth resistor is grounded; The voltage difference circuit is further used to match the impedance of the positive input terminal and the negative input terminal of the first operational amplifier by adjusting the resistance values ​​of the third resistor and the fourth resistor.

4. The voltage regulating circuit according to claim 3, characterized in that: The voltage difference circuit also includes: a first capacitor connected in parallel with the second resistor; A second capacitor is connected in parallel with the fourth resistor.

5. The voltage regulating circuit according to claim 1, wherein: The voltage feedback circuit includes a fifth resistor, a sixth resistor, a seventh resistor, a third capacitor, a fourth capacitor and a second operational amplifier; wherein: The positive input terminal of the second operational amplifier is connected to the output terminal of the voltage difference circuit, the negative input terminal of the second operational amplifier is respectively connected to the first end of the fifth resistor, the first end of the sixth resistor, the first end of the third capacitor and the first end of the fourth capacitor, the second end of the fifth resistor is connected to the positive output terminal of the DC-DC conversion circuit, the second end of the sixth resistor is grounded, the second end of the third capacitor is connected to the first end of the seventh resistor, and the second end of the seventh resistor is respectively connected to the second end of the fourth capacitor, the output terminal of the second operational amplifier and the comparison terminal of the DC-DC conversion circuit; The voltage feedback circuit is specifically used to control the DC-DC conversion circuit to adjust its output voltage so that the voltage value of the negative input terminal of the second operational amplifier tracks the voltage value of the positive input terminal thereof.

6. The voltage regulating circuit according to claim 1, characterized in that: The DC-DC conversion circuit includes a DC-DC controller, a switch tube, a sampling resistor, a transformer, a first rectifier diode and a second rectifier diode; wherein: The comparison end of the DC-DC controller is connected to the output end of the voltage feedback circuit, the detection end of the DC-DC controller is connected to the first end of the sampling resistor, the second end of the sampling resistor is grounded, the driving end of the DC-DC controller is connected to the control end of the switch tube, the first end of the switch tube is connected to the input negative end of the transformer, the input positive end of the transformer is connected to the power supply end of the DC-DC controller and the common end is connected to the DC power supply, the output positive end of the transformer is connected to the anode of the first rectifier diode, the cathode of the first rectifier diode serves as the output positive end of the DC-DC conversion circuit, the output negative end of the transformer is connected to the cathode of the second rectifier diode, the anode of the second rectifier diode serves as the output negative end of the DC-DC conversion circuit, and the middle tap of the transformer is grounded; The DC-DC conversion circuit is specifically used to adjust the duty cycle of the driving pulse of the switch tube according to the comparison result of the voltage inputted between its comparison terminal and the detection terminal, so as to adjust its output voltage.

7. The voltage regulating circuit according to claim 6, characterized in that: The DC-DC conversion circuit also includes a fifth capacitor and a sixth capacitor; wherein: The first end of the fifth capacitor is connected to the cathode of the first rectifier diode, the first end of the sixth capacitor is connected to the anode of the second rectifier diode, the second end of the fifth capacitor is connected to the second end of the sixth capacitor and the common end is grounded.

8. The voltage regulating circuit according to any one of claims 1 to 7, characterized in that: Positive output voltage of the DC-DC conversion circuit / (output voltage of the D / A converter-negative bias voltage)=output voltage of the positive linear regulator / output voltage of the D / A converter; Negative output voltage of the DC-DC conversion circuit / (output voltage of the D / A converter-negative bias voltage)=output voltage of the negative linear regulator / output voltage of the D / A converter.

9. An ultrasonic device, characterized in that: It comprises a transmitting chip and a voltage regulating circuit as described in any one of claims 1 to 8.

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