CN216562424U - Current generation circuit and driving chip - Google Patents

Abstract

The utility model discloses a current generation circuit and a driving chip for generating global current. Wherein, this circuit includes: the device comprises a current control module and a target current generation module, wherein the current control module receives a precise current and generates a global current according to the precise current; and the target current generation module is connected with the current control module and is used for adjusting the current starting point of the global current. The utility model solves the technical problem that the global current generated by the traditional constant current source driving circuit cannot drive the load.

Description

Current generation circuit and driving chip

Technical Field

The utility model relates to the field of display driving, in particular to a current generation circuit and a driving chip.

Background

In the application of the LED display driving chip, a circuit to be driven, namely a load, needs to be driven by current provided by a constant current source driving circuit. In the above process, the constant current source driving circuit part of the circuit plays a very important role, and the main role is to provide a global current with a zero temperature coefficient for the circuit to be driven, and then provide an output current to a load such as an LED lamp according to the global current so as to drive the LED lamp. In the process, the global current output by the constant current source driving circuit needs to be variable and adjustable, however, because the LED lamp cannot be turned on when the driving current is small, a plurality of ineffective adjusting gears exist in gears for adjusting the current in a constant current source driving circuit frame in the related art, which causes waste of circuit structure and performance, and the LED display screen has the problem that the LED display screen cannot be lighted due to low gray in the display process.

In view of the above problems, no effective solution has been proposed.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a current generation circuit and a driving chip, which at least solve the technical problem that the global current generated by a traditional constant current source driving circuit cannot drive a load.

According to an aspect of an embodiment of the present invention, there is provided a current generation circuit for generating a global current, including: the device comprises a current control module and a target current generation module, wherein the current control module receives a precise current and generates a global current according to the precise current; and the target current generation module is connected with the current control module and is used for adjusting the current starting point of the global current.

The target current generation module is adopted to adjust the current starting point of the global current, so that the purpose of ensuring that the current generation circuit can successfully drive the load when the global current is generated by adopting any gear in all gears is achieved, and the technical problem that the load cannot be driven by the global current generated by the traditional constant current source driving circuit is solved.

Optionally, the current generation circuit further comprises: and the current gain adjusting module is connected with the current control module and the target current generating module and is used for adjusting the current gain of the global current.

The current gain of the global current is adjusted by adopting the current gain adjusting module, so that the corresponding relation between the gear of the current generating circuit and the amplitude of the current gain is changed, the global current is accurately adjusted, and the current value adjusting range of the global current can be changed.

Optionally, the target current generation module includes at least one target current generation unit, and the at least one target current generation unit is connected to the current control module and is configured to adjust a current starting point of the global current.

Optionally, the target current generation unit includes: the first switching element is used for controlling the current starting point adjusting element to be connected with the current control module; the current starting point adjusting element is connected with the current control module through the first switching element; the target current generation unit is used for adjusting the current starting point of the global current by changing the connection state of the current starting point adjusting element and the current control module.

Optionally, the current starting point adjusting element includes: a first field effect transistor, the first switching element comprising a single pole, single throw switch.

Optionally, the current gain adjustment module comprises: at least one current gain adjustment unit, wherein the current gain adjustment unit is connected to the current control module and is configured to adjust a current gain of the global current.

Optionally, each of the current gain adjusting units includes: the second switching element is used for controlling the current gain adjusting element to be connected with the current control module; the current gain adjusting element is connected with the current control module through the second switch element; and the current gain adjusting unit is used for adjusting the current gain of the global current by changing the connection state of the current gain adjusting element and the current control module.

Optionally, the current gain adjustment element comprises: a second field effect transistor, the second switching element comprising a single pole, single throw switch.

Optionally, the current generation circuit further includes: and the controller is respectively connected with the target current generation module and the current gain adjustment module and is used for regulating and controlling the target current generation module and the current gain adjustment module according to the target value of the global current.

Optionally, the current generation circuit further includes: a bias module, wherein the bias module is connected to the current control module and is configured to provide the precise current to the current control module.

According to another aspect of the embodiment of the present invention, there is also provided a driving chip, wherein the driving chip includes any one of the above current generation circuits.

In an embodiment of the present invention, a current generation circuit for generating a global current is employed, wherein the current generation circuit includes: the current control module receives the accurate current and generates a global current according to the accurate current; the target current generation module is connected with the current control module and used for adjusting a current starting point of the global current, and the purpose of ensuring that the current generation circuit can successfully drive the load when generating the global current by adopting any gear in all gears is achieved, so that the technical effect of reducing circuit structure waste in the current generation circuit in the constant current source driving circuit frame is achieved, and the technical problem that the load cannot be driven by the global current generated by the traditional constant current source driving circuit is solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the utility model and together with the description serve to explain the utility model without limiting the utility model. In the drawings:

fig. 1 is a circuit diagram of a current mirror provided according to the related art;

FIG. 2 is a schematic diagram of a conventional current mirror output current provided according to the related art;

fig. 3 is a block diagram of a current generation circuit provided according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of providing global current according to an embodiment of the present invention;

FIG. 5 is a schematic illustration of another global current provided in accordance with an alternative embodiment of the present invention;

fig. 6 is a circuit diagram of a current generation circuit provided in accordance with an alternative embodiment of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the utility model described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

First, partial terms or terms appearing in the description of the embodiments of the present application are applied to the following explanations:

a Current mirror (Current mirror) is a circuit structure in a chip, and a Current with a certain proportion can be mirrored in the chip on the basis of a reference Current.

A MOS transistor, i.e., a field effect transistor, is an abbreviation of MOSFET, and a MOSFET metal-oxide semiconductor field effect transistor, which is abbreviated as a MOSFET, includes a G (gate), a S (source) and a D (drain) in the transistor.

The PMOS transistor is an n-type substrate, a p-channel MOS transistor that carries current by the flow of holes, and is also called a positive MOS.

The NMOS refers to a p-type substrate, an n-channel MOS tube and a Negative MOS.

The drain-source voltage difference is written as Vdsat, when the MOS tube enters a saturation region, the common amplifier and the current mirror CMOS tube need to work in the saturation region, and aiming at the current mirror structure, the larger the Vdsat is, the higher the current precision is.

The voltage difference between the drain and the source of the MOS tube is written as Vds, namely the voltage difference between the D and the S of the MOS tube.

The gate-source voltage difference of the MOS transistor is written as Vgs, namely the voltage difference between the G and S of the MOS transistor.

Example 1

Fig. 1 is a circuit diagram of a current mirror provided according to the related art, and as shown in fig. 1, this structure is a mature current mirror structure, which is basically used in a constant current source driving circuit architecture in the related art, and the operation principle is that, by making Vgs of two NMOS transistors M1 and M2 consistent and operating both transistors in a saturation region, a mirror output current proportional to Iin is mirrored from Iout, and the magnitude of the mirror current can be obtained according to a current formula of Iout ═ Iin × (Size2/Size1), where Size2 represents the channel width Size of an M2 transistor, Size1 represents the channel width Size of an M1 transistor, and it can be seen from the formula that the output current of the current mirror can be changed by changing the channel Size of a MOS transistor in the current mirror.

Further, fig. 2 is a schematic diagram of an output current of a conventional current mirror provided according to the related art, as shown in fig. 2, an abscissa represents an output current control gear of the conventional current mirror, and a line segment in the diagram represents the current mirror including 256 gears; the ordinate represents the output current of the current mirror. As can be seen from the figure, the gain curve of the output current of the conventional current mirror with the change of the gear is a straight line, and the output current gradually increases from 0 with the change of the gear. For some loads, such as LED lamps, when the output current provided by the constant current source driving circuit does not reach the minimum value for lighting the LED lamp, the LED lamp will not be lit. Until the output current can light the LED lamp, the gear adjustment carried out on the constant current source driving circuit before this is meaningless, and a plurality of output current adjustment gears of the current mirror lose the adjustment meaning, so that the actual change range of the output current is greatly reduced.

Fig. 3 is a block diagram of a current generation circuit according to an embodiment of the present invention, and as shown in fig. 3, the current generation circuit 30 includes a current control module 32 and a target current generation module 34, and the current generation circuit 30 is described in detail below:

and a current control module 32, configured to receive the precision current and generate a global current according to the precision current.

And a target current generation module 34 connected to the current control module for adjusting the current starting point of the global current.

The current generation circuit may be referred to as a constant current source drive circuit for driving a load, and the current generation circuit generates a global current, outputs the global current to the load after a predetermined process, and drives the load to perform a work. Alternatively, the load may be an LED lamp, and the magnitude of the current output to the LED may be adjusted by changing the global current of the constant current source driving circuit, so as to adjust the brightness of the LED lamp, and further control the display image of the LED display screen.

Alternatively, at least one of the precision current and the global current may be a zero temperature coefficient current, which is a current whose current value hardly changes with a temperature change. The current generation circuit can mirror stable and accurate current with zero temperature coefficient out of the global current required by the load through the circuit structure of the current generation circuit.

In the above structure, the target current generation module 34 solves the technical problem that the global current generated according to the precision current cannot drive the load when the current generation circuit is in a lower gear by adjusting the current starting point of the global current. Optionally, the current control module may include a plurality of gears, a global current with different current magnitudes may be generated according to the precise current and output corresponding to different gears, and a gear of the current control module may be referred to as a gear of the current generation circuit or the constant current source driving circuit. The starting point of the global current can be the size of the global current output by the current generation circuit when the current generation circuit is in the lowest gear, and the target current generation module enables the global current output by the current generation circuit under the condition of being in the lowest gear to still successfully drive the load by adjusting the current starting point of the global current.

As an optional implementation manner, the target current generation module may generate a step current with a fixed size, and the step current is merged into the global current to play a role of "raising" a current value of the global current, so that the global current output by the current generation circuit at any gear is at least greater than a value corresponding to the step current, and it is ensured that the output current output to the load according to the global current can stably drive the load, for example, when the load is an LED, a problem that the LED display screen is low in gray and cannot glow in the display process due to a small current value of the output current is solved.

In the above circuit configuration, a current generation circuit for generating a global current is employed, wherein the current generation circuit includes: the current control module receives the accurate current and generates a global current according to the accurate current; the target current generation module is connected with the current control module and used for adjusting a current starting point of the global current, and the purpose of ensuring that the current generation circuit can successfully drive the load when the global current is generated by adopting any gear in all gears is achieved, so that the technical effect of reducing circuit structure waste in the current generation circuit in the constant current source driving circuit framework is achieved, and the technical problem that the load cannot be driven by the global current generated by the traditional constant current source driving circuit is solved.

Fig. 4 is a schematic diagram of a global current provided according to an embodiment of the present invention, where, as shown in fig. 4, the ordinate represents the global current output by the current generating circuit, and the abscissa represents the gear position of the current generating circuit. It can be seen that even if the shift position of the current generation circuit is 0, the target current generation module can still change the current starting point of the global current by providing a "boost" current. Optionally, under the condition that the global current is used for driving the LED lamp, the current starting point may be set to a current magnitude that just can slightly light the LED lamp, so as to achieve the effect of ensuring that the global current output by the current generating circuit can light the LED lamp at all the gears, and avoid that the global current output by the current generating circuit is too small to light the LED lamp when the current generating circuit is at part of the low gears, which causes the gears to lose the adjusting significance.

As an optional embodiment, the current generation circuit may further include a bias module, wherein the bias module is connected to the current control module and is configured to provide a precise current for the current control module. In this optional embodiment, in order to ensure that the current of the input current control module is the zero-temperature-coefficient accurate current, the input current may be adjusted by the bias module to eliminate the current precision mismatch phenomenon of the input current, so as to obtain a stable and accurate current, and the accurate current is input to the current control module.

As an alternative embodiment, the target current generation module may include at least one target current generation unit, and the at least one target current generation unit is connected to the current control module and is used for adjusting the current starting point of the global current. In this optional embodiment, the target current generation module may also have a plurality of gears, and each target current generation unit may correspond to one gear of the target current generation module, so as to support a user to adjust the current starting point of the global current to a required current value.

As an alternative embodiment, the target current generation unit may include a first switching element and a current starting point adjustment element, wherein the first switching element is used for controlling the current starting point adjustment element to be connected with the current control module; the current starting point adjusting element is connected with the current control module through the first switching element; and the target current generation unit is used for adjusting the current starting point of the global current by changing the connection state of the current starting point adjusting element and the current control module. It should be noted that each target current generation unit may correspond to one shift position of the target current generation module, so that the shift position selection of the target current generation module may be controlled by the first switching element, and the current starting point of the global current may be freely changed according to the minimum current value required for driving the load.

As an alternative embodiment, the current starting point adjusting element may include a first field effect transistor, and the first switch element includes a single-pole single-throw switch, but it is understood by those skilled in the art that the current starting point adjusting element and the first switch element are illustrated as a field effect transistor and a single-pole single-throw switch, respectively, which do not constitute a limitation to the current starting point adjusting element and the first switch element, and any device that can achieve the same effect as the field effect transistor and the single-pole single-throw switch in the present invention is included in the protection scope of the present invention. For example, the first switching element may also be a register switch.

As an alternative embodiment, the current generation circuit may further include a current gain adjustment module, wherein the current gain adjustment module is connected to the current control module and the target current generation module, and is configured to adjust a current gain of the global current.

In this optional embodiment, when the constant current source driving circuit does not enable the current gain adjustment module, the current value of the global current linearly increases with the gear as shown in fig. 2; when the constant current source driving circuit starts the current gain adjusting module, the current gain adjusting module may adjust the current gain amplitude of the global current, where the current gain amplitude refers to changing the same gear of the constant current source driving circuit so that the amplitude of the output global current gain or the amplitude of the gain reduction is changed and is reflected in a schematic diagram of the global current of the constant current source driving circuit, that is, a slope of a broken line in fig. 5.

Fig. 5 is a schematic diagram of another global current provided according to an alternative embodiment of the present invention, and as shown in fig. 5, by adjusting the circuit structure of the current generation circuit through the current gain adjustment module, it is possible to implement that the gain amplitudes of the output global currents are different and the maximum value of the global current is amplified when the same shift level difference is changed.

As an alternative embodiment, the current gain adjusting module may comprise at least one current gain adjusting unit, wherein the current gain adjusting unit is connected with the current control module for adjusting the current gain of the global current. In this alternative embodiment, the current gain adjustment module may also have at least one gain step. It should be noted that each current gain adjustment unit may correspond to one gear of the current gain adjustment module, and the gear of the current gain adjustment module may be changed by changing the structure and the number of the current gain adjustment units connected to the current generation circuit, so as to change the current gain of the global current.

As an alternative embodiment, each current gain adjusting unit may include a second switching element and a current gain adjusting element, wherein the second switching element is used for controlling the current gain adjusting element to be connected with the current control module; the current gain adjusting element is connected with the current control module through the second switching element; and the current gain adjusting unit is used for adjusting the current gain of the global current by changing the connection state of the current gain adjusting element and the current control module. In this embodiment, each time the current control module is connected to one current gain adjustment element, the current gain amplitude of the gear to the global current can be refined. That is, every time a current gain adjustment element is connected, the current increase or decrease amplitude decreases by a certain value after adjusting a gear difference.

As an alternative embodiment, the current gain adjustment element may comprise a second field effect transistor and the second switching element comprises a single pole single throw switch. It will be understood by those skilled in the art that the current gain adjusting element and the second switching element are illustrated as a field effect transistor and a single-pole single-throw switch, respectively, and do not constitute a limitation to the current gain adjusting element and the second switching element, and any device that can achieve the same effect as the field effect transistor and the single-pole single-throw switch is included in the scope of the present invention. For example, the second switching element may also be a register switch.

As an alternative embodiment, the current generating circuit may include a controller, wherein the controller is respectively connected to the target current generating module and the current gain adjusting module, and is configured to regulate the target current generating module and the current gain adjusting module according to a target value of the global current. Wherein the target value of the global current is a current value which the user wants the global current to reach. After the controller obtains the target value of the global current, the controller can determine a current difference value by combining the current output value of the global current, determine a target gear according to the current difference value and the gear state of the current generation circuit, and then adjust the current generation circuit to the target gear by controlling the target current generation module and the current gain adjustment module, wherein the value of the global current output by the current generation circuit when the current generation circuit is in the target gear is the target value.

Optionally, the controller may adjust according to the following process: s1, according to the current gear state, the current global current value and the target value of the global current, firstly determining a reasonable target gear to enable the target gear to be close to the middle position in the total adjusting range; s2, calculating the ratio of the current difference value to the gear difference value to obtain a target current gain (current value/gear); s3, determining the target open-close state of each switch in the target current generation module and the current gain adjustment module according to the current gain (namely the current change value when each gear is adjusted currently) and the target current gain; s4, adjusting the state of each switch in the target current generation module and the current gain adjustment module to a target open-close state; and S5, the gear of the current control module is adjusted to the target gear from the current gear.

The utility model also provides a driving chip, which can comprise any one of the current generating circuits for generating the output current for driving the load, and solves the technical problem that the global current generated by the traditional constant current source driving circuit cannot drive the load. The current generation circuit included in the driving chip can generate a global current with an adjustable current starting point and an adjustable gain, and the driving chip can further perform certain processing on the global current to output the global current.

Fig. 6 is a circuit diagram of a current generation circuit provided in accordance with an alternative embodiment of the present invention. As an alternative embodiment, as shown in fig. 6, the current generation circuit may include a current control module 32, a target current generation module 34, a current gain adjustment module 36 and a bias module 38. The following detailed description is directed to the current generating circuit shown in fig. 6, and it will be understood by those skilled in the art that the following description of the circuit structure is only a preferred embodiment and is not intended to limit the technical solution of the present invention, and those skilled in the art may make modifications and amendments to the partial structure based on the inventive concept of the present invention, and these modifications and amendments should be included in the protection scope of the present invention.

The left Iin part of FIG. 6 includes a structure for providing input current, Rext is an external high precision resistor of 6K ohms, the operational amplifier realizes the clamping consistency of voltage, and an input current of zero temperature coefficient of 200uA is generated at the drain of the NMOS tube and is supplied to the bias module 38. The bias module 38 adjusts the input current, and then inputs the adjusted input current to a 200uA accurate current of the current control module 32 located in the Im-Iout part, and the accurate current is adjusted and stabilized by the bias module 38, so that the problem of current accuracy mismatch is avoided. The current control module 32 generates a global current according to the precision current, the current control module 32 is connected to the target current generation module 34 and the current gain adjustment module 36 at the same time, a "boost" current is obtained through the target current generation module 34, the current gain amplitude of the global current is adjusted through the current gain adjustment module 36, the global current is generated in a circuit for generating an Iout part, then the global current can be processed to obtain a driving load current, and a circuit structure for further processing the global current is not shown in the figure. The specific structure and function of each circuit block in fig. 6 will be described in detail below.

The bias module 38 may be a PMOS current mirror as shown, which is connected to a current source to obtain a stable current of 200 uA. The current is copied through a PMOS current mirror 1:1 and flows out from a Y point to obtain accurate current input into the current control module.

The current control module 32 may adopt an NMOS transistor current mirror structure with 8 gears, in the figure, the NMOS transistor on the left side 32i of the current mirror structure is connected in parallel with two NMOS transistors in the current gain adjustment module 36, and 8 groups of NMOS transistors corresponding to 8 gears on the right side of the current mirror structure are connected in parallel with the target current generation module 34. The <0> to <7> connected to the NMOS transistor may be register switches. In addition, the current generation circuit may further include an operational amplifier for clamping a potential, for example, a potential of an X point and a Y point.

In this alternative embodiment, i may be used to represent a unit channel size of the MOS transistor, and 64i means that the channel size of the MOS transistor is 64 × i, and since the size of the MOS transistor is in positive correlation with the current magnitude, it may be considered that currents flowing through the MOS transistor after the current is turned on are i and 64 i. In fig. 6, the current control module receives a 200uA precision current, and mirrors a global current through the current mirror structure, so that the constant current source driving circuit can output a current to the load according to the global current to drive the load such as an LED lamp. The magnitude of the mirror current of the current mirror can be determined according to a current formula Iout ═ Iin × (Size2/Size1), Iin represents the current input to the current mirror, Iout represents the current mirrored by the current mirror, Size1 represents the sum of the channel width sizes of the MOS transistors on the input current side of the current mirror, and Size2 represents the sum of the channel width sizes of the MOS transistors on the output current side of the current mirror. Therefore, the MOS transistor (not shown in the figure) on one side of the target current generation module may be controlled by the first switch element (not shown in the figure) to be connected to the current control module 32, and the MOS transistor in the current gain adjustment module 36 may be controlled by the second switch element to be connected to the current control module 32, so as to change the ratio of the sum of the sizes of the MOS transistors on both sides of the current mirror, and further change the magnitude of the mirrored global current, thereby implementing the regulation and control of the mirrored global current.

Alternatively, when the switches of the current gain adjusting module 36 and the target current generating module 34 are both turned off, if the current control module 32 is turned to the highest gear, the total size ratio of the MOS transistor channels on the left and right sides of the NMOS transistor current mirror is 32i/128i, so that Iout is 4 × Im, which is 800uA, where Im represents the accurate current obtained after passing through the PMOS current mirror. Since 8 exponentially increasing NMOS transistors (i.e., NMOS transistors within the frame of the current regulation module 32) are adopted on the current output side of the NMOS current mirror, the 800uA current gain can be divided into 256 steps, and the current gain corresponding to each step is 3.125 uA.

Because 2 parallel NMOS transistors (or more NMOS transistors, which are two NMOS transistors in the frame of the current gain adjustment module 36) are introduced to the current input side of the current mirror, and the access of the parallel NMOS transistors is controlled by using the register switch, when the current mirror is incorporated into the NMOS transistor of 32i, the size ratio of the current mirror on the left side to the current mirror on the right side is 64i/128i, so that Iout 2 Im is 400uA and 1.5625 uA/gear, and a new gain speed for increasing the output current along with the gear is provided. Conversely, the original 32i may be divided into two 16i, and the ratio of the sizes of the current mirrors on the left and right sides may be 16i/128i, so that Iout becomes 8 × Im 1600uA, 6.25 uA/shift, and the like. By the optional implementation mode, any current gain speed can be configured, and the configuration with the best current matching performance can be selected, so that the accuracy of the driving output current of the load is ensured.

Referring to fig. 5, if the Size1 on the current input side of the current mirror is 2 times larger than the Size1 on the input side, the gain of the output current generated at this time is only half the original gain per increase i in the MOS transistor Size on the current output side, and is reflected in fig. 5, that is, the slope of the broken line is smaller, according to the formula Iout ═ Iin ═ (Size2/Size 1). Through the optional embodiment, the gain amplitude corresponding to the gears of different output sides of the current mirror can be changed according to requirements, fine adjustment of output current when the output current is small is achieved, and the current adjustment precision is improved.

Alternatively, the width sizes of the plurality of current output side MOS tubes of the NMOS tube current mirror can be sequentially increased. For example, the size of the NMOS transistor on the current output side may be increased in an exponential manner of 2 on the basis of the reference size. For example, in the case of the first output side NMOS transistor having a size of 1, the sizes of each of the output side NMOS transistors in the following are 2,4,8, and 16 … …, respectively, by using a plurality of current output side NMOS transistors having increasing sizes, the number of output side NMOS transistors required to traverse all output current steps is reduced. For example, if all output side NMOS transistors are of the reference size, when the output global current needs to reach the size of 129 steps, 129 output side NMOS transistors of the reference size need to be connected in parallel on the output side of the current mirror; however, if the layout of the output side NMOS transistors is increased incrementally, only two NMOS transistors with the reference size of 1 and the reference size of 128 on the output side may be enabled, which greatly saves the hardware structure required in the current mirror.

It should be noted that, for the MOS transistor, the influence factor of the current accuracy is very complex, and specifically, the output current of the MOS transistor is determined by Vdsat, Vgs, Vds, Vth, and size, so that the output current deviates from the theoretical value as long as there is a parameter change Iout, and this problem can only be optimized, and cannot be completely solved. In addition, the accuracy of the current output by the MOS transistor is substantially in positive correlation with the channel size of the transistor, and therefore, when Iout takes a small value from zero, the accuracy of the output current of the MOS transistor is difficult to ensure. Therefore, optionally, the target current generation module can avoid the situation that the current value of the global current is too small by regulating the current starting point of the global current generated by the current control module, and adjust the gain of the global current of the current control module by the current gain adjustment module, so that the current precision of the global current can be improved by the above process.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

In the above embodiments of the present invention, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

Unless specifically stated otherwise, the relative arrangement of the components and values, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … … surface," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In the embodiments provided in the present application, it should be understood that the disclosed technology can be implemented in other ways. The above-described embodiments of the apparatus are merely illustrative, and for example, the division of the units may be a logical division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, units or modules, and may be in an electrical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a removable hard disk, a magnetic or optical disk, and other various media capable of storing program codes.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (10)

1. A current generation circuit, comprising: a current control module and a target current generation module, wherein,

the current control module receives a precision current and generates a global current according to the precision current;

and the target current generation module is connected with the current control module and is used for adjusting the current starting point of the global current.

2. The current generation circuit of claim 1, further comprising: and the current gain adjusting module is connected with the current control module and the target current generating module and is used for adjusting the current gain of the global current.

3. The current generation circuit according to claim 1 or 2, wherein the target current generation module comprises at least one target current generation unit, and the at least one target current generation unit is connected with the current control module and is used for adjusting the current starting point of the global current.

4. The current generation circuit according to claim 3, wherein the target current generation unit includes: a first switching element and a current starting point adjusting element, wherein,

the first switching element is used for controlling the current starting point adjusting element to be connected with the current control module;

the current starting point adjusting element is connected with the current control module through the first switching element;

the target current generation unit is used for adjusting the current starting point of the global current by changing the connection state of the current starting point adjusting element and the current control module.

5. The current generating circuit of claim 4, wherein the current initiation point adjusting element comprises: a first field effect transistor, the first switching element comprising a single pole, single throw switch.

6. The current generation circuit of claim 2, wherein the current gain adjustment module comprises: at least one current gain adjustment unit, wherein the current gain adjustment unit is connected to the current control module and is configured to adjust a current gain of the global current.

7. The current generation circuit of claim 6, wherein each of the current gain adjustment units comprises: a second switching element and a current gain adjustment element, wherein,

the second switch element is used for controlling the current gain adjusting element to be connected with the current control module;

the current gain adjusting element is connected with the current control module through the second switch element;

and the current gain adjusting unit is used for adjusting the current gain of the global current by changing the connection state of the current gain adjusting element and the current control module.

8. The current generation circuit of claim 7, wherein the current gain adjustment element comprises: a second field effect transistor, the second switching element comprising a single pole, single throw switch.

9. The current generation circuit of claim 2, further comprising: and the controller is respectively connected with the target current generation module and the current gain adjustment module and is used for regulating and controlling the target current generation module and the current gain adjustment module according to the target value of the global current.

10. A driver chip, characterized in that the driver chip comprises the current generation circuit of any one of claims 1 to 9.

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