Wide range high precision iv conversion circuit and method for power transfer real time monitoring

Abstract

The application provides a wide-range high-precision IV conversion circuit and method for real-time monitoring of power transmission, comprising a power transmission circuit, a current detection circuit, a reference voltage generation circuit, a double-comparator circuit, a Debounce circuit, an interval selection circuit, a software configuration selection circuit and a decoding circuit. The reference voltage generation circuit is used for selecting two of M reference voltages to output to the double-comparator circuit, the double-comparator circuit is used for comparing the detection voltage with a first comparison threshold voltage and a second comparison threshold voltage respectively, and the interval selection circuit is used for switching intervals according to the comparison results. The interval selection circuit is gradually switched to the best interval to which the detection current of the controllable transmission power tube belongs through a feedback loop, so as to adjust the controllable transmission power tube to achieve the best current mirror ratio, achieve the effect of optimizing the chip area and avoiding wrong gear selection while realizing high-precision, wide-range and real-time current detection of power transmission.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of integrated circuit design, and particularly relates to a wide-range high-precision IV conversion circuit and method for real-time monitoring of power transmission. BACKGROUND

[0002] The IV conversion circuit is used for converting a current signal into a voltage signal for measurement and processing, and is widely used in scenarios such as electronic measurement, control system and signal detection. At present, in the application of power transmission chips, it is generally necessary to implement wide-range high-precision current detection through the design of an IV conversion circuit while power transmission is being performed, so as to realize real-time monitoring and adjustment of the transmission power to achieve real-time protection of the chip. In the design of the IV conversion circuit, the factors to be considered mainly include conversion speed, conversion precision and conversion range. Among them, the conversion speed can be realized by improving the bandwidth of OP and other circuits, but the conversion precision and the conversion range exist the problem of mutual restriction, and the existing solutions to this problem are as follows:

[0003] (1) The output voltage is monitored by using an ADC or other monitoring circuit, and the mirror ratio is adjusted by using software to realize the precision of the mirror, so as to ensure the conversion precision of the current and voltage. Referring to Figure 1 , two PMOS tubes MP1 and MP2 are used to transmit power from the VIN end to the VOUT end, and a PMOS tube MP3 is used as a mirror tube of the MP1 and MP2 power tubes to detect the current in the power tube. The voltages at the VA node and the VB node are clamped by the operational amplifier 101 and the PMOS tube MP4 to ensure the accuracy of the current detection, and finally the detection current of the MP3 tube is converted into a voltage by the resistor XR1 to realize IV conversion. It can be seen that this scheme can change the mirror ratio of the power tube current by selecting the gate connection mode of the MP2 tube through external software control, but this circuit cannot adjust the mirror ratio autonomously. At the same time, since it also relies on an external monitoring circuit such as an ADC circuit to monitor the output voltage, the IV conversion time will be too long, which will increase the current detection response time of the circuit and make it impossible to effectively monitor the transmission power in real time. Especially in the application of monitoring the power tube current to realize overcurrent protection, the slow response may cause serious problems such as chip burning.

[0004] (2) The voltage converted by the current is compared with different reference voltages by using a plurality of comparators, so as to find the target interval and generate a corresponding control signal to adjust the mirror ratio according to the interval. Referring to Figure 2 , a comparator array module 2021 composed of M comparators is used in the control module, and the comparator array module 2021 inputs M different reference voltages VREF <m:1>and the output voltage VSENS of the current detection module is compared with M different reference voltages VREF respectively, and M comparison results are output to the decoding circuit, and the decoding circuit converts the M comparison results into N-bit binary code to generate the control signal. The current detection module generates the control signal SWEN <m:1>Adjusting the number of power tubes in the switch module and adjusting the output voltage point of the voltage generating module 2013, thereby realizing the real-time adjustment of the mirror ratio. It can be seen that this scheme can support high-precision, wide-range and real-time current detection, but its disadvantages are also obvious. In order to pursue high precision, more control gears are needed, which makes the comparator array module 2021 need to add more comparators, and using a large number of comparators will consume a lot of chip area, which is not conducive to the miniaturization design of the chip. In addition, if this scheme is applied to large-span gear adjustment, it may appear that the wrong gear is selected due to the IV conversion accuracy problem.

[0005] Therefore, in view of the above two schemes, there is a need for an IV conversion circuit and method that can achieve high-precision, wide-range and real-time current detection, optimize chip area and avoid wrong gear selection. SUMMARY

[0006] The wide-range high-precision IV conversion circuit and method for real-time monitoring of power transmission provided by the present application are mainly used to solve the problems that the existing IV conversion scheme cannot autonomously adjust the mirror ratio, the conversion time is too long, the chip area is large, and the wrong gear is selected, thereby achieving the effects of high-precision, wide-range and real-time current detection while optimizing the chip area and avoiding the wrong gear selection.

[0007] The present application achieves the above-mentioned purposes through the following technical solutions:

[0008] The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission includes a power transmission circuit, a current detection circuit and a control circuit, the power transmission circuit includes a plurality of controllable transmission power tubes for power transmission, the current detection circuit and the controllable transmission power tube constitute a current mirror circuit, which is used to detect the current when the controllable transmission power tube is turned on and convert it into a detection voltage output to the control circuit, the control circuit includes:

[0009] The reference voltage generating circuit is provided with M reference voltages of different sizes, two of which are selected as a first comparison threshold voltage and a second comparison threshold voltage and output to the double comparator circuit, the double comparator circuit inputs the detection voltage, compares the detection voltage with the first comparison threshold voltage and the second comparison threshold voltage respectively, and outputs comparison results to the interval selection circuit, the interval selection circuit is provided with M+1 different intervals according to the current detection range of the controllable power transmission tube when it is turned on, the threshold values of the M+1 different intervals correspond to the M reference voltages one by one, the interval selection circuit is used for switching intervals according to the comparison results, and outputs a first control signal and a second control signal to the reference voltage generating circuit and the power transmission circuit respectively to form a feedback loop, the reference voltage generating circuit is used for reselecting the corresponding two reference voltages according to the first control signal, the power transmission circuit is used for adjusting the number of controllable power transmission tubes turned on according to the second control signal, and the interval selection circuit switches to the best interval of the controllable power transmission tube detection current through the feedback loop, so that the controllable power transmission tube is adjusted to achieve the best current mirror ratio.

[0010] Further, the power transmission circuit includes a first MOS tube, a plurality of switches and M controllable power transmission tubes, the gate of the first MOS tube is connected to a first voltage, the source is connected to a second voltage, and the drain is connected to a voltage output terminal; the M controllable power transmission tubes are connected in parallel with the first MOS tube, and the gates are connected to the first voltage or the second voltage through the plurality of switches.

[0011] Further, the current detection circuit includes a second MOS tube, a clamping circuit and a voltage output circuit, the gate of the second MOS tube is connected to the first voltage, the source is connected to the second voltage, and the drain is connected to the first input terminal of the clamping circuit; the second input terminal of the clamping circuit is connected to the voltage output terminal of the power transmission circuit, for clamping the drain-source voltage of the controllable power transmission tube to be equal to the drain-source voltage of the second MOS tube, and outputting the detection current; the voltage output circuit adopts a voltage dividing resistor array, for selecting different voltage output gears according to the second control signal to convert the detection current into different sizes of the detection voltage output.

[0012] Further, the ratio of the detection current to the current of the voltage output terminal of the power transmission circuit is:

[0013]

[0014] wherein, (W / L) size of the second MOS transistor, i.e. the ratio of the width and length of the conductive channel, (W / L) size of the first MOS transistor and the MOS transistors in the M controllable power transmission tubes in the on state.

[0015] Further, the voltage output circuit further comprises a calibratable resistance connected to the output end of the clamping circuit, and the calibratable resistance is calibrated by a register to ensure that the IV conversion scale factor remains constant; the IV conversion scale factor is:

[0016]

[0017] wherein, the detection voltage, the resistance value of the calibratable resistance,

[0018]

[0019] wherein, the detection current, the terminal voltage of the calibratable resistance.

[0020] Further, the comparison logic of the double comparator circuit is that when the detection voltage is greater than the first comparison threshold voltage or the second comparison threshold voltage, the output comparison result is 1, and when it is less than the first comparison threshold voltage and the second comparison threshold voltage, the output comparison result is 0.

[0021] The output comparison result of the double comparator circuit is:

[0022] When the detection voltage is greater than the first comparison threshold voltage and the second comparison threshold voltage, the output comparison result is 11.

[0023] When the detection voltage is less than the first comparison threshold voltage and the second comparison threshold voltage, the output comparison result is 00.

[0024] When the detection voltage is between the first comparison threshold voltage and the second comparison threshold voltage, the output comparison result is 01.

[0025] Further, the interval selection circuit uses an N-bit binary number to represent M+1 different intervals, and the Mth interval is represented by a binary number DRV <n-1>: .

[0026] If the binary number DRV <n-1>The larger, the greater the current detection value corresponding to the interval, the interval switching logic is:

[0027] The condition that the current interval is the best interval is that the comparison result is 11, the binary number DRV <n-1>is all ones; or the comparison result is 00, binary number DRV <n-1>is 00; or the comparison result is 01.

[0028] when the comparison result is 11, the binary number DRV <n-1>for non-all-ones, the binary number DRV <n-1>Add 1, i.e. up one interval.

[0029] When the comparison result is 00, the binary number DRV <n-1>DRV = 0 for all 1's <n-1>Down 1, namely, down one interval.

[0030] Further, the scheme is also provided with a software configuration selection circuit, which is connected with the output end of the interval selection circuit, used for providing a software configuration value, and selecting one of the binary number and the software configuration value as the output.

[0031] Further, the scheme is also provided with a decoding circuit, which adopts thermometer decoding, used for converting the binary number or the software configuration value into a thermometer code as the second control signal output, the thermometer code including M+1 different values, the greater the value is, the more the number of the controllable transmission power tube is turned on and the greater the voltage division ratio of the voltage division resistor array is.

[0032] The wide-range high-precision IV conversion method for power transmission real-time monitoring is applied to the wide-range high-precision IV conversion circuit for power transmission real-time monitoring, and includes:

[0033] S1: the power transmission circuit transmits power through the first MOS tube and the M controllable transmission power tubes, and the reference voltage generation circuit selects two initial reference voltages to output.

[0034] S2: the current detection circuit detects the on-current of the first MOS tube and the controllable transmission power tube and converts it into a detection voltage to output; the double comparator circuit compares the detection voltage with the two reference voltages respectively and outputs a comparison result.

[0035] S3: the interval selection circuit judges whether the current interval is the best interval according to the comparison result, if yes, the interval is kept; if no, the interval is switched, and the first control signal and the second control signal are output.

[0036] S4: the reference voltage generation circuit reselects the corresponding two reference voltages to output according to the first control signal, and the power transmission circuit adjusts the number of the controllable transmission power tubes turned on and the voltage division ratio of the voltage division resistor array according to the second control signal, and returns to execute step S2.

[0037] Therefore, the present application has the following beneficial effects:

[0038] 1、The present application compares and judges the detection voltage, outputs the control signal to adjust the reference voltage generated circuit to select the two reference voltages and the number of power tubes turned on, and gradually reaches the best interval by using the feedback control loop, compared with the traditional software external control switch state adjustment mirror ratio or the scheme of using multiple comparators, the present application can autonomously adjust the mirror ratio, and only needs to use a double comparator circuit to gradually compare the detection voltage with multiple reference voltages, greatly optimizes the chip area, reduces the hardware consumption of chip design, and reduces the cost.

[0039] 2、The present application divides the detection current range into multiple current intervals, and gradually switches to the best interval through the step interval switching mode, so that the wrong gear selection during switching can be avoided.

[0040] 3、The present application can set the interval size according to actual needs, so as to realize more fine mirror ratio and automatic adjustment of output voltage division ratio, and also realize high current-voltage conversion precision in a wide current transmission range.

[0041] The present application will be further described in detail below in combination with the drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 is a schematic diagram of the prior art scheme (1) IV conversion circuit.

[0043] Figure 2 is a schematic diagram of the prior art scheme (2) IV conversion circuit.

[0044] Figure 3 is a schematic diagram of the wide range high precision IV conversion circuit of the embodiment of the present application.

[0045] Figure 4 is a schematic diagram of the power transmission circuit and the current detection circuit of the embodiment of the present application.

[0046] Figure 5 is a schematic diagram of the reference voltage generation circuit and the double comparator circuit of the embodiment of the present application

[0047] Figure 6 is a schematic diagram of the Debounce circuit of the embodiment of the present application.

[0048] Figure 7 is a schematic diagram of the software configuration selection circuit of the embodiment of the present application.

[0049] Figure 8 is a flow chart of the wide range high precision IV conversion method of the embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the described embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0051] Wide-range high-precision IV conversion circuit for real-time monitoring of power transmission

[0052] Referring to Figure 3 The embodiments of the present application relate to a wide-range high-precision IV conversion circuit for real-time monitoring of power transmission, which comprises a power transmission circuit 10, a current detection circuit 20 and a control circuit. The power transmission circuit 10 comprises a plurality of controllable transmission power tubes for power transmission. The current detection circuit 20 and the controllable transmission power tubes constitute a current mirror circuit, which is used to detect the current when the controllable transmission power tubes are turned on and convert it into a detection voltage output to the control circuit.

[0053] The control circuit comprises a reference voltage generation circuit 30, a double-comparator circuit 40 and an interval selection circuit 60. The reference voltage generation circuit 30 is provided with M reference voltages of different sizes, which are used to select two reference voltages as a first comparison threshold voltage and a second comparison threshold voltage, respectively, and output them to the double-comparator circuit 40. The double-comparator circuit 40 inputs the detection voltage, which is used to compare the detection voltage with the first comparison threshold voltage and the second comparison threshold voltage, respectively, and output the comparison results to the interval selection circuit 60. The interval selection circuit 60 is provided with M+1 different intervals according to the current detection range when the controllable transmission power tubes are turned on. The threshold values of the M+1 different intervals correspond to the M reference voltages one by one. The interval selection circuit 60 is used to switch the interval according to the comparison results, and output a first control signal and a second control signal to the reference voltage generation circuit 30 and the power transmission circuit 10, respectively, so as to constitute a feedback loop. The reference voltage generation circuit 30 is used to select the corresponding two reference voltages according to the first control signal. The power transmission circuit 10 is used to adjust the number of controllable transmission power tubes turned on according to the second control signal. The interval selection circuit 60 gradually switches to the best interval of the detection current of the controllable transmission power tubes through the feedback loop, so as to adjust the controllable transmission power tubes to achieve the best current mirror ratio.

[0054] Referring to Figure 4 In the embodiment, the power transmission circuit 10 further comprises a first MOS transistor MP10, a plurality of switches and M controllable transmission power transistors, the gate of the first MOS transistor MP10 is connected to a first voltage, the source is connected to a second voltage, and the drain is connected to the voltage output terminal; the M controllable transmission power transistors are connected in parallel with the first MOS transistor MP10, and the gates thereof are connected to the first voltage or the second voltage through the plurality of switches.

[0055] Specifically, the first MOS transistor MP10 and the M controllable transmission power transistors in the embodiment are all PMOS transistors, the sources of which are connected to the second voltage as the power supply voltage, and the drains are connected to the voltage output terminal. The first voltage is smaller than the second voltage. Since the gate voltage of the first MOS transistor MP10 is always lower than the source voltage, it is always in the on state; the M controllable transmission power transistors switch the input voltage of the gate through the switch control, so as to switch the on or off state of the controllable transmission power transistor. Specifically, if the gate is connected to the second voltage signal, the gate voltage is lower than the source voltage, at this time, the channel is formed between the source and the drain, the PMOS transistor is turned on, and the current flows from the source to the drain; if the gate is connected to the first voltage signal, the gate voltage is equal to the source voltage, the channel between the source and the drain is closed, and the PMOS transistor is turned off.

[0056] In the embodiment, the current detection circuit 20 comprises a second MOS transistor MP2, a clamping circuit and a voltage output circuit, the gate of the second MOS transistor MP2 is connected to the first voltage, the source is connected to the second voltage, and the drain is connected to the first input terminal of the clamping circuit; the second input terminal of the clamping circuit is connected to the voltage output terminal of the power transmission circuit 10, for clamping the drain-source voltage of the controllable transmission power transistor and the drain-source voltage of the second MOS transistor MP2 to the same size, and outputting the detection current; the voltage output circuit adopts a voltage dividing resistor array, for selecting different voltage output gears according to the second control signal, so as to convert the detection current into detection voltage output of different sizes.

[0057] Specifically, the second MOS transistor MP2 in the embodiment is a PMOS transistor same as the first MOS transistor MP10 and the M controllable transmission power transistors, so as to form a current mirror circuit for accurately mirroring the current. Under the same biasing condition, the current generated when the controllable transmission power transistor is turned on can be accurately copied, so as to obtain the detection current.

[0058] In the embodiment, the ratio of the detection current to the current of the voltage output terminal of the power transmission circuit 10 is:

[0059]

[0060] wherein, a ratio of width and length of the conductive channel of the second MOS transistor, a sum of (W / L) sizes of the first MOS transistor and MOS transistors in the M controllable power transmission transistors in the on state.

[0061] Specifically, the clamping circuit includes a clamping amplifier and a third MOS transistor MP3. The non-inverting input terminal of the clamping amplifier is connected with the drain of the controllable power transmission transistor, the inverting input terminal of the clamping amplifier is connected with the drain of the second MOS transistor MP2, and the output terminal of the clamping amplifier is connected with the gate of the third MOS transistor MP3. The source of the third MOS transistor MP3 is connected with the drain of the second MOS transistor MP2, and the drain of the third MOS transistor MP3 is connected with the voltage output circuit. The clamping amplifier is used to clamp the voltages of the two input terminals to the same size, so as to ensure that the drain-source voltages VDS of the PMOS transistors MP10- MP1M and the drain-source voltages VDS of the mirror transistors MP2 in the power transmission circuit 10 are equal, and then ensure that the current flowing through the two is a fixed set value.

[0062] Specifically, the process of converting the detection current into the detection voltage output includes a calibration and a voltage division process. The voltage output circuit adopts a calibratable resistor XR1, and the drain of the third MOS transistor MP3 is connected to the ground through the calibratable resistor XR1, which is used to calibrate the calibratable resistor XR1 through a register to generate a calibration voltage. The voltage division resistor array is connected in parallel with the calibratable resistor XR1, and includes M voltage division resistors XR21-XR2M and M control switches. The voltage division resistors XR21-XR2M are connected in series, and the M control switches are connected in parallel with the voltage division resistors XR21-XR2M, respectively. When the control switch is in the off state, the voltage division resistor connected in parallel with the control switch is connected for voltage division; if closed, the voltage division resistor is in a short-circuit state. By controlling the number of voltage division resistors connected in the voltage division resistor array, different voltage output gears can be selected.

[0063] The calibration voltage is:

[0064]

[0065] wherein, the detection current, a resistance value of the calibratable resistor XR1.

[0066] The ratio of the output detection voltage and the calibration voltage is set as K, and there is:

[0067]

[0068] wherein, The detection voltage output after calibration and voltage division.

[0069] From equations (2) and (3), we have:

[0070]

[0071] wherein, is the voltage output current of the power transfer circuit 10.

[0072] IV conversion factor is:

[0073]

[0074] From equation (4), we have:

[0075]

[0076] From equation (5), the deviation of the power tube mirror ratio and the resistance caused by the process is compensated by the calibratable resistance XR1, and the calibration voltage is divided by the voltage division resistance array to generate the detection voltage, so that the product of the current mirror ratio and the resistance division ratio in each interval remains unchanged, that is, the parameter K can be offset by the size of the power tube current mirror, so that the IV conversion factor remains constant. It can be seen that in any mirror case, the ratio of the voltage output current of the power transfer circuit 10 to the detection voltage is a fixed value.

[0077] Referring to Figure 5 , specifically, the reference voltage generation circuit 30 includes a power supply circuit, a voltage conversion circuit, a voltage division circuit, and an output circuit. The power supply module is used to provide a reference voltage. The voltage conversion module is used to convert the reference voltage into a target voltage. The voltage division module includes M voltage output terminals, which are used to divide the target voltage and output reference voltages of different sizes from the M voltage output terminals to the output circuit, respectively. The output circuit is provided with a first voltage output terminal and a second voltage output terminal, and includes 2M control switches. Two of the 2M control switches are connected in parallel to form a group, and the group is connected in series with the M voltage output terminals. One control switch in each group is connected to the first voltage output terminal, and the other control switch in each group is connected to the second voltage output terminal.

[0078] In this embodiment, the comparison logic of the dual comparator circuit 40 is that when the detection voltage is greater than the first comparison threshold voltage or the second comparison threshold voltage, the comparison result is 1, and when it is less than, the output is 0.

[0079] The comparison result output by the dual comparator circuit 40 is:

[0080] When the detection voltage is greater than the first and second comparison threshold voltages, the comparison result is output as 11.

[0081] When the detection voltage is less than the first and second comparison threshold voltages, the comparison result is output as 00.

[0082] When the detection voltage is between the first and second comparison threshold voltages, the comparison result is output as 01.

[0083] Specifically, the double-comparator circuit 40 of the embodiment includes a front comparator U1 and a rear comparator U2. The same-phase input end of the front comparator U1 inputs the detection voltage, and the opposite-phase input end inputs the first comparison threshold voltage. The same-phase input end of the rear comparator U1 inputs the detection voltage, and the opposite-phase input end inputs the second comparison threshold voltage. The first comparison threshold voltage is greater than the second comparison threshold voltage, so the comparison result cannot be 10.

[0084] Referring to Figure 6 Specifically, the embodiment further includes a Debounce circuit 50, the input end of which is connected with the output end of the double-comparator circuit 40. The Debounce circuit 50 adopts a timer-based Debounce algorithm and is provided with multiple timers for effectively preventing false shaking caused by power supply or other interference. When a signal change is detected, a timer is started. If the signal changes again within a set stable time CK_deb, the timer is reset. Only when the timer reaches the set stable time CK_deb can the transmitted comparison result be confirmed to be stable, thereby ensuring the stability of signal transmission.

[0085] In the embodiment, the interval selection circuit 60 adopts an N-bit binary number to represent M+1 different intervals. The Mth interval is represented as a binary number DRV <n-1>: .

[0086] If the binary number DRV <n-1>The larger the value, the larger the current detection value corresponding to the interval, and the interval switching logic is:

[0087] The condition that the current interval is the optimal interval is that the comparison result is 11, the binary number DRV <n-1>is all ones. Or the comparison result is 00, binary number DRV <n-1>is 00. Or the comparison result is 01.

[0088] When the comparison result is 11, the binary number DRV <n-1>for non-all-ones, the binary number DRV <n-1>Add 1, i.e. up one interval.

[0089] When the comparison result is 00, the binary number DRV <n-1>DRV = 0 for all 1's <n-1>Down 1, i.e. down one interval.

[0090] Specifically, the interval selection circuit 60 in this embodiment is taken as an example with 8 intervals, at this time M=7, N=3, if the current detection range of the controllable transmission power tube when conducting is 0-70mA, then set the current switching points as 10mA, 20mA, 30mA, 40mA, 50mA, 60mA, 70mA with 10mA as the increment, and the corresponding reference voltages are VREF1-VREF7 respectively. The 8 intervals are respectively: [0, 10mA), [10mA, 20mA), [20mA, 30mA), [30mA, 40mA), [40mA, 50mA), [50mA, 60mA), [60mA, 70mA), [70mA, +. The binary number corresponding to the above interval output is represented by three bits as DRV <n-1>=3' b000, DRV <n-1>=3' b001, DRV <n-1>=3' b010, DRV <n-1>= 3' b011, DRV <n-1>= 3' b100, DRV <n-1>=3' b101, DRV <n-1>=3' b 110, DRV <n-1>=3' b111. The first control signals corresponding to the above eight binary numbers are:

[0091] VREFO<1:0> = {VREF1, VREF1}, VREFO<1:0> = {VREF2, VREF1}, VREFO<1:0> = {VREF3, VREF2}, VREFO<1:0> = {VREF4, VREF3}, VREFO<1:0> = {VREF5, VREF4}, VREFO<1:0> = {VREF6, VREF5}, VREFO<1:0> = {VREF7, VREF7}, VREFO<1:0> = {VREF7, VREF7}.

[0092] In this embodiment, a software configuration selection circuit 70 is further included, which is connected with the output terminal of the interval selection circuit 60, for providing a software configuration value, and selecting one of the binary number and the software configuration value to output.

[0093] Referring to Figure 7 In particular, the software configuration circuit in this embodiment generally adopts the automatic hardware selection interval as described above, and selects the software configuration value to output when debugging or performing special configuration interval. The software configuration circuit is driven by inputting a software driving signal SOFTDRVEN and inputting a software configuration value SOFTDRV <n-1:0>to retain flexibility of software configuration.

[0094] In the embodiment, a decoding circuit 80 is further included, which adopts thermometer decoding to convert the binary numbers or software configuration values into thermometer codes as the second control signals, the thermometer codes including M+1 different values, and the greater the value is, the more the controllable transmission power tubes are turned on and the greater the voltage division ratio of the voltage division resistor array is.

[0095] Specifically, taking the interval selection circuit 60 with 8 intervals as an example, the second control signals corresponding to the above-mentioned 8 binary numbers are represented by thermometer decoding as follows: SWEN <m:1>=7' b0000000, SWEN <m:1>=7' b0000001, SWEN <m:1>= 7'b0000011, SWEN <m:1>=7' b0000111, SWEN <m:1>=7' b0001111, SWEN <m:1>=7' b0011111, SWEN <m:1>= 7'b0111111, SWEN <m:1>=7'b1111111.

[0096] Wide-range high-precision IV conversion method for real-time monitoring of power transmission

[0097] With reference to Figure 2 The embodiments of the present application relate to a wide-range high-precision IV conversion method for real-time monitoring of power transmission, which is applied to a wide-range high-precision IV conversion circuit for real-time monitoring of power transmission and comprises:

[0098] S1: The power transmission circuit 10 transmits power through the first MOS transistor MP10 and M controllable transmission power transistors, and the reference voltage generation circuit 30 selects two initial reference voltages.

[0099] S2: The current detection circuit 20 detects the on-current of the first MOS transistor MP10 and the controllable transmission power transistors and converts it into a detection voltage output; the double comparator circuit 40 compares the detection voltage with the two reference voltages respectively and outputs a comparison result.

[0100] S3: The interval selection circuit 60 determines whether the current interval is the best interval according to the comparison result, and if yes, the interval is maintained; if no, the interval is switched, and a first control signal and a second control signal are output.

[0101] S4: The reference voltage generation circuit 30 reselects the corresponding two reference voltage outputs according to the first control signal, and the power transmission circuit 10 adjusts the on-quantity of the controllable transmission power transistors and the voltage division ratio of the voltage division resistor array according to the second control signal, and returns to step S2.

[0102] Specifically, the interval selection circuit 60 is taken as an example with 8 intervals, M=7 and N=3, and the current detection range of the controllable transmission power transistors when on is 0-70 mA, and the voltage interval is set with 10 mA as an increment. The working process of the IV conversion circuit is as follows:

[0103] When the power transmission starts, the highest interval is selected by default, and DRV <n-1>= 3' b111, SWEN <m:1>= 7'b1111111, the reference voltage generating module outputs VREFO<1:0> = {VREF7, VREF7}. If the current of the power transmission is detected as 15 mA, after the first comparison and denounce, at this time DRV <n-1>of the value of the variable X minus 1, becomes 3'bl 10, SWEN <m:1>The value of VREF0<1:0> becomes 7'b0111111, and the value of VREFO<1:0> becomes {VREF7, VREF6}. Since the current range corresponding to the interval at this time is (60mA~70mA), the interval continues to be adjusted step by step downward until DRV <n-1>to 3'b001, SWEN <m:1>VREF0<1:0> changes to {VREF2, VREF1}, at this time the interval corresponding current range is (10mA~20mA), the best interval is reached, and maintained in the interval until the power transmission current changes, and the above process is repeated.

[0104] The above embodiments are only preferred embodiments of the present application, and cannot be used to limit the scope of protection of the present application. Any non-essential changes and substitutions made by those skilled in the art on the basis of the present application shall fall within the scope of protection of the present application. ​

Claims

1. A wide-range, high-precision IV-V conversion circuit for real-time monitoring of power transfer, comprising a power transfer circuit, a current detection circuit, and a control circuit, wherein the power transfer circuit includes a plurality of controllable power transfer transistors for power transfer, and the current detection circuit and the controllable power transfer transistors form a current mirror circuit for detecting the current when the controllable power transfer transistors are turned on and converting it into a detection voltage output to the control circuit, characterized in that, The control circuit comprises: The reference voltage generating circuit is provided with M reference voltages of different sizes, two of which are selected as a first comparison threshold voltage and a second comparison threshold voltage and output to the double-comparator circuit; the double-comparator circuit inputs the detection voltage and compares the detection voltage with the first comparison threshold voltage and the second comparison threshold voltage respectively, and outputs comparison results to the interval selection circuit; the interval selection circuit is provided with M+1 different intervals according to the current detection range of the controllable power transmission tube when it is turned on, the threshold values of the M+1 different intervals correspond to the M reference voltages one by one, the interval selection circuit is used to switch intervals according to the comparison results, and outputs a first control signal and a second control signal to the reference voltage generating circuit and the power transmission circuit respectively to form a feedback loop; the reference voltage generating circuit is used to reselect the corresponding two reference voltages according to the first control signal; the power transmission circuit is used to adjust the number of controllable power transmission tubes turned on according to the second control signal; the interval selection circuit switches to the best interval of the controllable power transmission tube detection current through the feedback loop, so as to realize the adjustment of the controllable power transmission tube to achieve the best current mirror ratio.

2. The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 1, wherein: The power transmission circuit comprises a first MOS tube, a plurality of switches and M controllable power transmission tubes; the gate of the first MOS tube is connected to a first voltage, the source thereof is connected to a second voltage, and the drain thereof is connected to a voltage output terminal; the M controllable power transmission tubes are connected in parallel with the first MOS tube, and the gates thereof are connected to the first voltage or the second voltage through the plurality of switches.

3. The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 2, wherein: The current detection circuit comprises a second MOS tube, a clamping circuit and a voltage output circuit; the gate of the second MOS tube is connected to the first voltage, the source thereof is connected to the second voltage, and the drain thereof is connected to a first input terminal of the clamping circuit; a second input terminal of the clamping circuit is connected to a voltage output terminal of the power transmission circuit, for clamping the drain-source voltage of the controllable power transmission tube to be equal to the drain-source voltage of the second MOS tube, and outputting the detection current; the voltage output circuit adopts a voltage dividing resistor array, for selecting different voltage output levels according to the second control signal to convert the detection current into detection voltages of different sizes.

4. The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 3, wherein: The ratio of the detection current to the current of the voltage output terminal of the power transmission circuit is: wherein, is the (W / L) size of the second MOS transistor, i.e. the ratio between the width and the length of the conductive channel, is the sum of the (W / L) sizes of the first MOS transistor and the MOS transistors of the M controllable power transmission tubes that are in the on state.

5. The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 4, wherein: The voltage output circuit further comprises a calibratable resistor connected to the output end of the clamping circuit, and the calibratable resistor is calibrated by a register to ensure that an IV conversion scale factor remains constant; the IV conversion scale factor is: wherein is the detection voltage, is the resistance value of the calibratable resistance, is: wherein, is the detected current, is the end voltage of the calibratable resistance. 6.The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to any one of claims 1-5, characterized in that: The comparison logic of the double-comparator circuit is that when the detection voltage is greater than the first comparison threshold voltage or the second comparison threshold voltage, the comparison result is 1, and when the detection voltage is less than the first comparison threshold voltage and the second comparison threshold voltage, the comparison result is 0; The comparison result output by the double-comparator circuit is: When the detection voltage is greater than the first comparison threshold voltage and the second comparison threshold voltage, the comparison result is 11; When the detection voltage is less than the first comparison threshold voltage and the second comparison threshold voltage, the comparison result is 00; When the detection voltage is between the first comparison threshold voltage and the second comparison threshold voltage, the comparison result is 01. 7.The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 5, characterized in that: The interval selection circuit uses N-bit binary numbers to represent M+1 different intervals, and the Mth interval is represented as a binary number DRV <n-1> ： ；< / n-1> If the binary number DRV <n-1>The greater the value, the greater the current detection value corresponding to the interval, and the interval switching logic is: the condition that the current interval is the best interval is that the comparison result is 11, binary number DRV <n-1>is all ones; or the comparison result is 00, binary number DRV <n-1>All 0; or the comparison result is 01; When the comparison result is 11, the binary number DRV <n-1>for non-all-ones, the binary number DRV <n-1>Add 1, i.e., increase an interval; when the comparison result is 00, the binary number DRV <n-1>DRV = 0 for all 1's <n-1>Subtract 1, i.e., decrease an interval. 8.The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 7, characterized in that: It further comprises a software configuration selection circuit connected to the output end of the interval selection circuit, for providing a software configuration value and selecting one of the binary number and the software configuration value as an output. 9.The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to claim 8, characterized in that: It further comprises a decoding circuit, which adopts thermometer decoding to convert the binary number or the software configuration value into a thermometer code as the second control signal output, and the thermometer code comprises M+1 different values, and the greater the value, the greater the number of turn-on of the controllable transmission power tube and the greater the voltage division ratio of the voltage division resistor array.

10. A wide range high precision IV conversion method for power transfer real time monitoring characterized in that, The wide-range high-precision IV conversion circuit for real-time monitoring of power transmission according to any one of claims 1-9 comprises: S1: the power transmission circuit transmits power through a first MOS tube and M controllable transmission power tubes, and the reference voltage generation circuit selects two initial reference voltages as outputs; S2: the current detection circuit detects the conduction current of the first MOS tube and the controllable transmission power tubes and converts it into a detection voltage output; the double-comparator circuit compares the detection voltage with the two reference voltages respectively and outputs a comparison result; S3: the interval selection circuit determines whether the current interval is the best interval according to the comparison result, and if yes, the interval is maintained; if no, the interval is switched, and a first control signal and a second control signal are output. S4: the reference voltage generating circuit reselects the corresponding two reference voltage outputs according to the first control signal, and the power transmission circuit adjusts the number of conduction of the controllable transmission power tube and the voltage division ratio of the voltage division resistance array according to the second control signal, and returns to execute step S2.

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