MULTI-AREA CURRENT SENSOR TECHNOLOGIES

Abstract

A circuit configured to provide a representation of a load current, the circuit comprising: several shunt resistors, wherein a first shunt resistor of the several shunt resistors has a different type and resistance value than the other shunt resistors of the several shunt resistors, and wherein each shunt resistor of the several shunt resistors is configured to selectively conduct the load current; several gain resistors, including a first gain resistor of the same resistance type as the first shunt resistor, wherein the first gain resistor is a different resistance type than the other gain resistors of the several gain resistors; and a first switch configured to couple the first shunt resistor to the load in a first state and to disconnect the first shunt resistor from the load in a second state.

Description

TECHNICAL AREA OF REVELATION

[0001] The present disclosure relates to current sensing circuits and in particular techniques for multi-range current sensing. BACKGROUND

[0002] Current monitoring circuits can be used to monitor and report the load current information of a system. A conventional way to detect the current is to use a shunt resistor in series with the current flow path and measure the voltage that develops across the shunt resistor. Due to Ohm's law, the voltage across the shunt resistor terminal is proportional to the current through the resistor. A current sensor circuit works with the shunt resistor to produce an output signal that is proportional to the current through the shunt resistor. One source of error for a current sensor circuit is offset error, which is caused by finite open-loop gain or device mismatch. The offset error has the greatest impact on the current monitoring output accuracy when the input signal is small.If the input signal is large relative to the offset error, the output accuracy improves because the measured signal is larger than the offset error in the current monitoring device itself. However, larger signals generally reduce system efficiency, while smaller signals pose a challenge to accuracy. In some systems, it is necessary to report load current information with high accuracy over a span of several decades. SUMMARY OF THE REVELATION

[0003] Techniques for improving multi-range current sensing are provided. In one example, a circuit may include multiple shunt resistors, multiple gain resistors, and a first switch. The first shunt resistor in the multiple shunt resistors may be of a different type and resistance value than the other shunt resistors in the multiple shunt resistors. The multiple gain resistors may include a first gain resistor of the same type as the first shunt resistor. The first gain resistor may have a different type and resistance value than the other gain resistors in the multiple gain resistors. The switch may be configured to couple the first shunt resistor to the load in a first state and to disconnect the first shunt resistor from the load in a second state.

[0004] This section is intended to provide an overview of the subject matter of the present patent application. It is not intended to provide an exclusive or exhaustive explanation of the invention. The detailed description is included to provide further information about the present patent application. List of characters

[0005] In the drawings, which are not necessarily drawn to scale, the same numbers may describe similar components in different views. The same numbers with different letter suffixes may represent different instances of similar components. The drawings generally illustrate various embodiments discussed in this document as examples and not as limitations. Fig. Figure 1 illustrates a general system that includes an exemplary current sensor circuit. Fig. Figure 2 shows the transient simulation result of the exemplary current sensing circuit from Fig. 1. Fig. Figure 3 shows the transient simulation result, as in Fig. 2 shown, for a time between 4.2 ms and 5.8 ms. Fig. Figure 4 shows the simulation result between the time 4.9 ms and 5.12 ms. Fig. Figure 5 shows the control signals of switches Sm1 - Sm6 and Stf1 - Stf9 when the current sensor circuit switches between different ranges. Fig. Figure 6 shows a general implementation of a system that includes a general implementation of an exemplary multi-range current sensor circuit. Fig. Figure 7 illustrates a general system that features an exemplary multi-range current sensor design with more than one power supply providing the load current. Fig. Figure 8 illustrates a general alternative example system. Fig. Figure 9 illustrates a general flowchart of an exemplary method for operating a multi-range current sensor according to the present invention. DETAILED DESCRIPTION

[0006] A multi-range current monitoring circuit can detect current over a wide range with good accuracy. Such a circuit can utilize multiple shunt resistors with varying values ​​to monitor the current and provide a scaled representation of the current level of a unidirectional or bidirectional load current supplied by one or more power supplies. Depending on the current level, the appropriate shunt resistor can be selected to conduct the current.Selecting the appropriate shunt resistor according to the magnitude of the sensing current can ensure that the input signal to the current monitoring device is always within a reasonable range; accordingly, the effect of the offset error on the output accuracy of the current monitoring device is minimized, while using a small shunt resistor to minimize efficiency degradation.

[0007] A low-temperature coefficient (TC) shunt resistor is typically used in current monitoring devices where the output accuracy depends on the absolute resistance value of the shunt resistor. For conventional multi-range current monitoring circuits, this can mean that several low-TC shunt resistors are required. The cost of discrete low-TC shunt resistors is generally high relative to the overall system cost. This is especially true for conventional multi-range current monitoring circuits that employ many multiple shunt resistors.

[0008] The present inventors have identified techniques for a multi-range current monitoring architecture that can help eliminate or reduce the number of discrete low-temperature shunt resistors by using shunt resistors and gain resistors made of different materials. By using shunt and gain resistors made of the same material, the output accuracy of the current monitoring device can be made independent of the absolute resistance value of the shunt resistor. Furthermore, in certain applications, the multi-range current monitoring architecture can utilize shunt resistors made of different materials to detect current in different ranges.For example, shunt and gain resistors for low sensing currents can be implemented using thin-film material; for medium sensing currents, they can be implemented using a metallization resistor; for high sensing currents, they can be implemented using a bismaleimide triazine resin (BT) substrate; and for ultra-high sensing currents, they can be implemented using copper on a PCB or by using discrete low-temperature resistors. In certain examples, a metal shunt resistor with a BT substrate can be used to sensing currents of approximately 100 amperes. Such a shunt resistor can have a copper conducting medium and can be fabricated to have a footprint of approximately 20.00 millimeters (mm) by 25.97 mm.

[0009] Fig. 1 illustrates a general system 100 , which is an exemplary current sensor circuit 101 exhibits. The system 100 can a power supply, the current sensor circuit 101 and a burden 102 exhibit. In some examples, the provision of services can 102 It includes a voltage regulator. The current sensing circuit 101 can the current (I L ), which is provided by the benefit provider 102 to the load 103 is delivered, monitor and can provide a scaled representation (I ÜBERW The output of the supplied current is provided as an output. In some examples, the output of the current sensing circuit can be... 101 as a feedback mechanism for power supply 102 It can be used, but is not so restricted.

[0010] The current sensor circuit 101can accommodate multiple shunt resistors, multiple gain resistors (Rtfs1, Rtfs2, Rms), multiple switches (Stf1-Stf9, Sm1-Sm6) and a conversion circuit arrangement 104 exhibit, in order to represent (I ÜBERW ) of the recorded current (I L ) to provide. In certain examples, the current sensor circuit can 101 Use thin-film (tf) and metal-on-silicon (m) resistors as the shunt resistors. In certain examples, the conversion circuit arrangement can 104 a pair of amplifiers ( A1 and A2 ) and optionally an output resistance ( R0 ), an optional voltage reference 105 and a control system 106 exhibit the control 106 can the scaled representation (I OBERW ) at the output of the current sensing circuit 101monitors and can control the switches (Stf1-Stf9, Sm1-Sm6) to adjust the best detection range for the level of the detected current in most cases.

[0011] During operation, one of the shunt resistors (Rms, Rtfs and Rtfs2) and one of the gain resistors (Rmg and Rtfg) can be selected and controlled by the current sensor circuit. 101 can be used. The gain and shunt resistor, which are used by the current sensor circuit. 101The resistors used are referred to here as the selected gain and shunt resistors. The selected gain and shunt resistors are of the same resistance type. In certain examples, the selected gain and shunt resistors can be adjacent to each other, so that they share the same operating temperature. In certain examples, an integrated circuit can include the selected gain and shunt resistors, and the selected gain and shunt resistors can be entangled, so that they share the same operating temperature.A resistor type is defined by a resistor that is made from a specific type of material or exhibits a specific temperature coefficient (TC) characteristic. For example, a thin-film resistor is one resistor type, a metal resistor is another, and a discrete low-TC shunt resistor is another. The illustrated example is from [reference missing]. Fig. 1 has a metal resistance modulus 107 including a metal shunt resistor (Rms) and a metal reinforcement resistor (Rmg). The illustrated example from Fig. 1 also features a thin-film resistance modulus 108This includes several thin-film shunt resistors (Rtfs1, Rtfs2) and one thin-film reinforcement resistor (Rtfg). Resistor types that can be used include, but are not limited to, diffusion resistors, polyresistors, thin-film resistors, metal resistors, or matched low-temperature resistors. In some examples, the resistors can be integrated on a semiconductor substrate, a bismaleimide triazine resin (BT) substrate, or a printed circuit board (PCB) substrate.

[0012] During operation, an output (V) can be used. AUS ) the provision of services 102 Power via the current sensing circuit 101 to an input node (V LAST ) the load 103 supply. A first group of switches (Stf1, Stf7, Sm1) can act to connect a selected shunt resistor in series between the power supply. 102 and the burden 103to couple. A second group of switches (Stf2, Stf3, Stf8, Stf9, Sm2, Sm3) can act to connect each node of the selected shunt resistor to an input of each amplifier ( A1 , A2 ) to couple. A third group of switches (Stf5, Sm5) can be used to couple a selected gain resistor with a feedback network of the first amplifier ( A1 ) to couple. A fourth group of switches (Stf6, Sm6) can serve as Kelvin connections to the selected gain resistor and do not conduct DC current during operation.

[0013] The illustrated current sensor circuit 101 It has three different detection ranges, but the present invention is not limited in this way. If the current sensor circuit 101Operating in the lowest sensing range, thin-film resistors Rtfs2 and Rtfg can be used as the selected shunt and gain resistors. In certain examples, the lowest sensing range can correspond to the highest resolution range. If the current sensor circuit 101 When operating in the mid-range sensing range, thin-film resistors Rtfs1 and Rtfg can be used as the selected shunt and gain resistors. When the current sensor circuit operates in the highest sensing range, metal resistors Rms and Rmg can be used as the selected shunt and gain resistors. In certain examples, the highest sensing range may correspond to the lowest resolution range. Resistors Rtfs1, Rtfs2, and Rtfg are made of a thin-film material that exhibits a very low temperature coefficient (TC) characteristic, and Rtfg should follow Rtfs1 and Rtfs2 with respect to temperature to minimize temperature drift.

[0014] The following example describes the operation of the current sensor circuit. 101 and assumes that the current sensing circuit 101 It operates in the highest detection range. Therefore, switches Sm1 to Sm6 are closed. The power supply 102 can power be supplied via a load current (I) L ) in the provision of services 102 supplied voltage to the load 103 supply. The load current (I L ) can the load 102 The signal passes through the selected shunt resistor Rms and the switch Sm1 and can develop a detection voltage (Vs) across the selected shunt resistor (Rms). The detection voltage (Vs) can be specified by: Vs = vp − v = iL ⋅ Rms . If the amplifiers ( A1 and A2When the nodes are in equilibrium, the node voltages "vp" and "vn" are reflected onto nodes "vp1" and "vn1". A current (ig) is drawn from the first amplifier ( A1 ) supplied through switch Sm4 to the gain resistor (Rmg) and the current (ig) flows from Rmg to the second amplifier ( A2 The current through Rmg can be given by: ig = ( vp 1 − vn 1 ) / Rmg = ( vp − vn ) / Rmg = IL ⋅ Rms / Rmg . The second output terminal of the first amplifier ( A1 ) or a third amplifier (α) can introduce a current, α·ig, into an output resistance ( R0 ) feed in. In certain examples, the second output of the third amplifier (α) can be implemented via a current-dependent amplifier or a current source, such as a ratio current mirror. The scaled representation (I ÜBERW ) of the load current (I L ) can be given by: I SUPERV = α ⋅ ig ⋅ R0 + Vref . By substituting GI. 2 for “ig” in GI. 3, the I ÜBERW -Voltage can be expressed as follows: I SUPERV = IL ⋅ α ⋅ R0 ⋅ Rms / Rmg + Vref . Eq. 4 shows that the quality of the scaled representation (I ÜBERW ) depends on α, Vref, Ro and the ratio between the selected gain and shunt resistance (e.g., Rms, Rmg). In this example, the selected shunt resistance (Rms) can control the load current (I L) conduct and can be a metal resistor. The conductive material for a metal resistor in silicon processes is typically aluminum, which has a temperature coefficient (TC) of 0.36% / °C. The accuracy of the current measurement depends on the consistency of the ratio of the selected shunt and gain resistor (e.g., Rms / Rmg) across the operating temperature. Therefore, the selected gain resistor can have the same or nearly the same TC as the selected shunt resistor if the selected gain resistor (Rmg) has the same construction as the Rms and they share the operating temperature. Exemplary design techniques for the gain and shunt resistor using metal layers for optimized temperature sharing are detailed in U.S. Patent Application No. 16 / 539,404, entitled “SHUNT RESISTOR AVERAGING TECHNIQUES,” filed on 13 [date missing].Discussed in August 2019, this is hereby incorporated in its entirety by reference. Metal resistors can have a relatively low surface rho and may be better suited to conducting a current that is too large, relative to a silicon area, to be handled by thin-film material. Metal-type shunt resistors can be manufactured in the range of values ​​from a few tens of ohms down to a few milliohms (mΩ).

[0015] In the illustrated example from Fig. 1. Thin-film shunt resistors (Rtfs1, Rtfs2) can be used if the load current (I) L) in the medium or low range. The thin-film shunt resistors can be thin-film resistors and can have values ​​from a few tens of ohms to hundreds of kilohms. The thin-film gain resistor (Rtfg) can be used together with the thin-film shunt resistors (Rtfs1, Rtfs2). A thin-film material typically has a higher area rho compared to metal and is advantageous for manufacturing resistors with values ​​in the range of a few tens to a few hundred kΩ. The operating principle of the current sensing circuit 101 is independent of the type of resistive material for the selected shunt and gain resistor. In the illustrated example from Fig. 1 depends on the quality of the representation (I ÜBERWThe load current, when thin-film resistors are selected, depends on the ratio Rtfs1 / Rtfg or Rtfs2 / Rtfg. Switches Sm1-Sm6 and Stf1-Stf9 allow the current monitoring device to operate in different detection ranges. The selection of which sensor range to use can be made manually or automatically via the controller. 106 based on the representation (I ÜBERW ) of the load current can be programmed.

[0016] Fig. Figure 2 shows the transient simulation result of the exemplary current sensing circuit from Fig. 1. The simulation results are presented graphically. 201 of the current that is passed through the shunt resistor (RMS), a graphical representation 202 of the current that is passed through the first thin-film shunt resistor (Rtfs1), a graphical representation 203of the current that is passed through the second thin-film shunt resistor (Rtfs2), a graphical representation 204 the voltage difference between the output voltage (V AUS ) and the load voltage (V LAST ), a graphical representation 205 of the load current (I L ), a graphical representation 206 the representation of the load current (I OBERW ) and a graphical representation 207 of the error in the representation of the load current (I OBERW ). In the simulation setting, the load current ranges from -25 mA to 25 mA. The positive polarity of the load current is defined as a load current flowing from the power supply to the load. Switches Stf2-Stf8 and Sm1-Sm6 change their states when the magnitude of the load current exceeds the thresholds of ±2.5 mA, ±250 µA, and ±25 µA. The graphical representation 207The diagram below shows the output error of the current monitoring circuit. At time 0s, when the load current is -25 mA, the shunt resistor Rms is selected to conduct the load current. This puts the current monitoring circuit into its highest current monitoring range. As the simulation time increases, the magnitude of the load current, and therefore the input signal to the current monitoring device, decreases. A smaller input signal means that the output of the current sensor circuit is more sensitive to input offset errors from A1 and A2.

[0017] At time 4.5 ms (IL = -2.5 mA), switches Stf1 to Stf6 and Sm1 to Sm6 change their states to select Rtfs1 as the shunt resistor. At this point, Rtfs1 and Rtfg are selected. The current sensor output jumps back to near the negative full-scale deflection immediately after the switches change their states. The moment the range changes, the input signal level recovers to a reasonable level relative to the range's full-scale deflection. Now with Rtfs1 selected, the signal across the selected shunt resistor is larger relative to the offset error of A1 and A2, and the output error of the current monitor decreases.

[0018] If the magnitude of the load current continues to decrease until 4.95 ms (IL = -250 µA), the current monitoring device changes its range. Switches Stf1-Stf3 and Stf7-Stf9 change their states to select Rtfs2 and Rtfg for current sensing. By selecting Rtfs2 as the shunt resistor, the current sensor operates in its lowest sensing range. The voltage across "V" is measured the instantaneously after the range change. AUS “ and “V LAST “ again large and the output error of the power monitoring device becomes smaller. The load current is at time = 5 ms 0Aand increases until it reaches 25 mA at 10 ms. If the load current changes from 0 A to full scale between 5 ms and 10 ms, the current monitor changes its sensing range from low to high. When the load current approaches 250 µA at 5.05 ms, Rtfs1 and Rtfg are selected as the shunt and gain resistors. As the load current continues to increase and approaches 2.5 mA at 5.5 ms, Rms and Rmg are selected as the shunt and gain resistors.

[0019] Fig. Figure 3 shows the transient simulation result, as in Fig. Figure 2 shows a time range between 4.2 ms and 5.8 ms and provides a clearer picture of the range change events at 4.5 ms and 5.5 ms.

[0020] Fig. Figure 4 shows the simulation result from Fig. 2 between the time 4.9 ms and 5.12 ms and provides a clearer picture for the range change events at 4.95 ms and at 5.05 ms.

[0021] Fig. Figure 5 shows the control signals of switches Sm1 - Sm6 and Stf1 - Stf9 when the current sensor circuit is off. Fig. 2 switches between different areas. Fig. 5 shows a graphical representation 501 of the control signals of switches Sm1-Sm5, a graphical representation 502 of the control signals for Stf1-Stf3, a graphical representation 503The diagram shows the control signals for Stf7-Stf9 and a graphical representation of the control signals for Stf4-Stf6. When the current sensor circuit operates in the highest detection range (time < 4.5 ms and > 5.5 ms), switches Sm1-Sm6 are in the closed position. When the current sensor circuit operates in the second-highest detection range (4.5 ms < time < 4.95 ms and 5.05 ms < time < 5.5 ms), switches Stf1-Stf3 and Stf4-Stf6 are in the closed position. When the current sensor circuit operates in the lowest detection range (4.95 ms < time < 5.05 ms), switches Stf7-Stf9 and Stf4-Stf6 are in the closed position.

[0022] The design example in Fig. Figure 1 shows a possible arrangement where the gain and shunt resistors are made of multiple materials: two shunt resistors and one gain resistor as a thin film; and one gain and one shunt resistor as a metal. The proposed architecture is not limited to just one gain resistor of each type. A current monitoring circuit based on the proposed architecture could include multiple shunt resistors and multiple gain resistors made of a first resistor type, and multiple gain resistors and multiple shunt resistors based on a second resistor type. The idea of ​​using multiple gain and shunt resistors made of different resistive materials is not limited to the use of only two resistor types.For example, a current sensor based on the proposed architecture could use a thin-film resistor for low-current sensing, a metal resistor for medium-current sensing, and a third type of resistor, such as a discrete resistor, for high-current sensing.

[0023] Fig. Figure 6 shows a general implementation of a system 600 , which is a general implementation of an exemplary multi-range current sensor circuit 601 The system features a multi-range current sensor circuit. 601 , a benefit provision 602 and a burden 603 exhibit the multi-range current sensor circuit. 601 It can include shunt (Ras, Rbs, ..., Rxs) and gain (Rag, Rbg, ..., Rxg) resistors made from different resistor types: R-type A, R-type B, ..., R-type X. The conversion circuit arrangement 604can use the gain and shunt resistors to generate an output signal (I ÜBERW ) to produce the magnitude and polarity of the load current (I L ) represents. When the gain and shunt resistors (Rag and Ras) of the first resistor type are selected, switches Sa1-Sa6 are closed and couple the voltages of both terminals of the selected gain resistor (Rag) and the selected shunt resistor (Ras) to the conversion circuit arrangement. 604 Similarly, when the resistors (Rbg and Rbs) of the second resistor type are selected, switches Sb1-Sb6 are closed to connect the voltages at both terminals of the selected gain resistor (Rbg) and the selected shunt resistor (Rbs) to the conversion circuit arrangement. 604to couple. If the resistors (Rxg and Rxs) of resistor type X are selected, the corresponding switches Sx1-Sx6 are closed to connect the upper and lower terminals of the selected gain resistor (Rxg) and the selected shunt resistor (Rxs) to the conversion circuit arrangement. 604 to couple. The output signal (I ÜBERW ) of the multi-range current sensor circuit 601 It can be a voltage output or a current signal.

[0024] Fig. Figure 7 illustrates a general system featuring an exemplary multi-range current sensor design with more than one power supply providing the load current. A first power supply 712 It can be a controller with a strong ability to supply and draw current and a second power supply. 702 Can a controller with a power supply be increased compared to the first one? 712Its ability to supply and draw current may be weak. This arrangement may have certain advantages over the example system. 600 out of Fig. 6. In high-current operation, switching DC-DC converters can provide the load current (I). L ) more efficient than linear regulators, which can have higher power losses. In such cases, a DC-DC converter can be used for the initial power supply. 712 can be used and can reduce the load 703 drive during periods of high current demand. The example system 700 It can also reduce the number of switches in series with the shunt resistors (e.g., Rbs, Ras). In contrast to the example from Fig. 6. In configuration 6, where the shunt resistors (Ras, Rbs, ..., Rxs) are in series with the corresponding switches (e.g., Sa1, Sb1, ..., Sx1), the shunt resistors (Ras, Rbs), if selected, can directly connect the corresponding power supply to the shunt resistor. Eliminating the switch series coupling of the shunt resistor to the corresponding power supply can reduce design complexity and cost, since the switch in series with the shunt resistor in the highest current range can handle the full-scale load current (I). L can cope. With reference to Fig. 7 can provide the second benefit 702 , if the load current (I LIf the current is low, the load current is supplied through the corresponding shunt resistor (Rbs). Switches Sa2-Sa6 are open and Sb2-Sb6 are closed to select the gain resistor (Rbg) and the shunt resistor (Rbs). If type B resistors (Rbg, Rbs) are selected, the output signal (I) can be... ÜBERW ) of the multi-range current monitoring device 701 the output stream (I L2 ) of the second power supply. If the load current (I L ) is high, the first benefit payment can 712 the load current (I L ) provided by the corresponding shunt resistor (Ras). Switches Sa2-Sa6 are closed and Sb2-Sb6 are open to select the gain resistor (Rag) and the shunt resistor (Ras). If type A resistors are selected, the output signal (I) ÜBERW ) of the multi-range current monitoring device 701 the output stream (I L1) specify the first benefit payment.

[0025] Fig. Figure 8 illustrates a general alternative example system. This system can be configured with at least one fewer amplifier than the example system from [reference missing]. Fig. 7 can be used. The system can provide initial power. 812 , a second benefit provision 802 , a multi-range current monitoring circuit 801 and a burden 803 exhibit. The multi-range current monitoring circuit 801 shunt resistors (Ras, Rbs), gain resistors (Rag, Rbg), multiple switches (Sa1, Sa2, Sa3, Sb1, Sb2, Sb3) can have an optional output resistor ( R0 ), an optional voltage reference 805 and a control system 806 exhibit the control 806 can the scaled representation (I ÜBERW ) at the output of the current sensing circuit 801It monitors and can control the switches (Sa1, Sa2, Sa3, Sb1, Sb2, Sb3) to adjust the optimal detection range for the level of the detected current in most cases. In certain examples, the first power supply 812 It can be a controller with a strong ability to supply and draw current, and can be the second power supply. 802 a controller with a power supply that is lower than the first one 812 It may have a weak ability to supply and draw current. Compared to the circuit made of Fig. 7 indicates the multi-range current monitoring circuit 801 a single amplifier instead of two amplifiers. When switches Sb1-Sb3 are closed and the other switches are open, the load current (I) flows. L ) through the shunt resistor (Rbs) on the left. When switches Sa1-Sa3 are closed and the other switches are open, the load current (I) flows. L) through the shunt resistor (Ras) on the right side. The amplifier A1 The first terminal of the selected shunt resistor (Ras or Rbs) can be coupled to the first terminal of the selected gain resistor (Rag or Rbg). The second terminals of the selected gain and shunt resistors are physically coupled.

[0026] Fig. Figure 9 illustrates a general flowchart of an exemplary method for operating a multi-range current sensor according to the present invention. 901 A first shunt resistor can be selectively coupled to conduct a load current. The first shunt resistor can be one of two or more shunt resistors of the multi-range current sensor. 903 Nodes of the selected shunt resistor can be selectively coupled to a first node of a first amplifier and a first node of a second amplifier. When 905A first gain resistor among several gain resistors can be selectively coupled between a second input of the first amplifier and a second input of the second amplifier. In certain examples, the selected gain resistor, the first gain resistor, can have the same structural and material construction as the selected shunt resistor. In other examples, the selected shunt resistor and the selected gain resistor can have a different structural and material construction than one or more of the other shunt and gain resistors. Such a construction can include the same conductive material, the same substrate material, or a combination thereof. 907A first node of the selected gain resistor can be selectively coupled to an output of the first amplifier. In certain examples, a signal at the second node of the selected gain resistor can be processed as a feedback signal for the second amplifier. 909 A representation of the load current within a first range can be provided at the output of the first amplifier. A representation of the load current within a second range can be provided by selecting and replacing the first shunt resistor and possibly the first gain resistor with different values ​​from the multiple shunt and gain resistors, as long as the selected shunt and gain resistors are of the same type, as discussed above. NOTES AND EXAMPLES

[0027] In a first example, Example 1, a circuit for providing a representation of a load current may include: several shunt resistors, wherein a first shunt resistor of the several shunt resistors has a different type and resistance value than the other shunt resistors of the several shunt resistors, and wherein each shunt resistor of the several shunt resistors is configured to selectively conduct the load current; several gain resistors, including a first gain resistor of the same resistance type as the first shunt resistor, wherein the first gain resistor is a different resistance type than the other gain resistors of the several gain resistors; and a first switch configured to couple the first shunt resistor to the load in a first state and to disconnect the first shunt resistor from the load in a second state.

[0028] In Example 2, the multiple shunt resistors from Example 1 optionally have more than two individually selectable shunt resistors.

[0029] In Example 3, an integrated circuit may optionally include at least two of the multiple shunt resistors from one or more of Examples 1-2.

[0030] In Example 4, the integrated circuit consisting of one or more of Examples 1-3 optionally includes an amplifier that is selectively coupled to the first gain resistor.

[0031] In Example 5, the integrated circuit from one or more of Examples 1-4 optionally includes a controller configured to control the first switch.

[0032] In Example 6, a first shunt resistor of the multiple shunt resistors from one or more of Examples 1-2 optionally has a laminate substrate.

[0033] In Example 7, the laminate substrate is optionally a bismaleimide triazine resin (BT) substrate, consisting of one or more of Examples 1-6.

[0034] In Example 8, the circuit from one or more of Examples 1-7 optionally includes several switches configured to configure the circuit for a first current sensing area of ​​several current sensing areas, wherein the multiple switches include the first switch.

[0035] In Example 9, a method for operating a multi-range current sensing circuit may include: selectively coupling a first shunt resistor of several shunt resistors to conduct a load current, selectively coupling a node of the first shunt resistor to a first node of a first amplifier, selectively coupling a first gain resistor of several gain resistors to a second input of the first amplifier, selectively coupling a first node of the first gain resistor to an output of the first amplifier, providing a representation of the load current over a first range at the output of the first amplifier, and wherein the first shunt resistor and the first gain resistor have conductive media of the same material.

[0036] In Example 10, the first shunt resistor and the first gain resistor from one or more of Examples 1-9 optionally have the same substrate material.

[0037] In Example 11, the method from one or more of Examples 1-10 optionally captures the load current representation, which approaches an extreme of the first range.

[0038] In Example 12, the method from one or more of Examples 1-11 optionally includes: isolating the first shunt resistor from conducting the load current and from the first amplifier in response to a detection that the representation of the load current is approaching the extreme of the first range; selectively isolating the first gain resistor from the first amplifier in response to a detection that the representation of the load current is approaching the extreme of the first range; and selectively coupling a second shunt resistor to conduct the load current and a second gain resistor to the amplifier to detect the load and provide a representation of the load current over a second range.

[0039] In Example 13, the second range from one or more of Examples 1-12 is optionally higher than the first range.

[0040] In Example 14, the selective coupling of a node of the first shunt resistor from one or more of Examples 1-13 optionally includes selective coupling of a node of the first shunt resistor with a first node of a first amplifier; and with a first node of a second amplifier, and the selective coupling of a first gain resistor of several gain resistors from one or more of Examples 1-13 optionally includes selective coupling of a first gain resistor of several gain resistors between a second input of the first amplifier and a second input of the second amplifier.

[0041] In Example 15, a multi-range current sensing circuit may include: multiple means of shunting a load current, one means of providing a representation of the load current, and multiple means of providing amplification for the means of providing the representation of the load current.

[0042] In Example 16, a conductive material of a first means of several means for bypassing the load current and a conductive material of a first means for providing amplification from one or more of Examples 1-15 are optionally a first material.

[0043] In Example 17, a conductive material of a second means of the multiple means for bypassing the load current and a conductive material of a second means for providing amplification from one or more of Examples 1-16 are optionally a second material.

[0044] In Example 18, a substrate material of the first means of several means for bypassing the load current and a substrate material of the first means for providing amplification from one or more of Examples 1-17 are optionally a first substrate material.

[0045] In Example 19, a substrate material of the second means of the multiple means for bypassing the load current and a substrate material of the second means for providing amplification from one or more of Examples 1-18 are optionally a second substrate material.

[0046] In Example 20, the multiple means for shunting the load current, the means for providing the representation of the load current, and the multiple means for providing an amplification from one or more of Examples 1-19 are optionally configured to provide the representation using at least three resolution ranges.

[0047] The detailed description above refers to the accompanying drawings, which form part of the detailed description. The drawings illustrate specific embodiments in which the invention can be implemented. These embodiments are also referred to here as "examples." Such examples may include elements in addition to those shown or described. However, the inventors of the present invention also intend to provide examples in which only those elements shown or described are provided.Furthermore, the inventors of the present invention also intend to provide examples that use any combination or permutation of the elements shown or described (or one or more aspects thereof), either with reference to a specific example (or one or more aspects thereof) or with reference to other examples (or one or more aspects thereof) shown or described herein. The detailed description above includes references to the accompanying drawings, which form part of the detailed description. The drawings illustrate specific embodiments in which the invention can be implemented. These embodiments are also referred to herein as "examples." Such examples may include elements in addition to those shown or described.However, the inventors of the present invention also intend to provide examples in which only those elements shown or described are provided. Furthermore, the inventors of the present invention also intend to provide examples that use any combination or permutation of those elements shown or described (or one or more aspects thereof), either with reference to a specific example (or one or more aspects thereof) or with reference to other examples (or one or more aspects thereof) shown or described herein.

[0048] In the event of inconsistent usage between this document and any other documents incorporated by reference, the usage in this document shall prevail.

[0049] In this document, the terms "a," "an," or "a" are used as is customary in patent documents to include one or more than one, irrespective of any other instances or uses of "at least one" or "one or more." In this document, the term "or" is used to refer to a non-exclusive "or," so that it includes "A or B," "A but not B," "B but not A," and "A and B," unless otherwise specified. In this document, the terms "including" and "with" are used as the equivalents of the respective terms "showing" and "whereby" in plain English.Furthermore, the terms "including" and "comprising" are open expressions, meaning that a system, device, article, composition, formulation, or process that includes elements in addition to those listed under such a term will still be considered to fall within the scope of protection of that subject matter of the invention. Moreover, the terms "first," "second," and "third," etc., as they may appear in a claim, are used merely as descriptive terms and are not intended to impose any numerical requirements regarding their objects.

[0050] The process examples described here may be at least partially machine- or computer-implemented. Some examples may include a computer-readable or machine-readable medium encoded with instructions capable of configuring an electronic device to perform processes as described in the examples above. An implementation of such processes may include code such as microcode, assembly language code, code of a higher-level programming language, or the like. Such code may contain computer-readable instructions for performing various processes. The code may form parts of computer program products. Furthermore, in one example, the code may be stored tangible on one or more non-volatile, non-persistent, or persistent tangible computer-readable media, such as during execution or at other times.Examples of these tangible, computer-readable media may include hard disks, removable magnetic disks, removable optical disks (e.g., compact disks and digital video disks), magnetic cassettes, memory cards or sticks, random access memory (RAMs), read-only memory (ROMs), and the like.

[0051] The above description is intended to be illustrative and not limiting. For example, the examples described above (or one or more aspects thereof) may be used in combination with one another. Other embodiments may be used, as might be the case for a person skilled in the art, when reviewing the above description. The summary is provided to enable the reader to quickly determine the nature of the technical disclosure. It is presented with the understanding that it is not to be used to interpret or limit the scope of protection or the meaning of any claim. Furthermore, in the above detailed description, various features may be grouped together to streamline the disclosure. This should not be interpreted as an intention that an unclaimed disclosed feature is essential to any claim.Rather, the subject matter of the invention may consist of fewer than all features of a particular disclosed embodiment. The following aspects are hereby included in the detailed description as examples or embodiments, each aspect constituting a separate embodiment on its own, and it is intended that such embodiments may be combined with one another in various combinations or permutations.

[0052] Aspects of the present disclosure relate to techniques for improved multi-range current sensing. In one example, a circuit may include multiple shunt resistors, multiple gain resistors, and a first switch. A first shunt resistor of the multiple shunt resistors may be of a different type than the other shunt resistors of the multiple shunt resistors. The multiple gain resistors may include a first gain resistor of the same resistor type as the first shunt resistor. The first gain resistor may be of a different type than the other gain resistors of the multiple gain resistors. The switch may be configured to couple the first shunt resistor to the load in a first state and to disconnect the first shunt resistor from the load in a second state.

Claims

[1] Circuit configured to provide a representation of a load current, wherein the circuit comprises: multiple shunt resistors, wherein a first shunt resistor of the multiple shunt resistors has a different type and resistance value than the other shunt resistors of the multiple shunt resistors, and wherein each shunt resistor of the multiple shunt resistors is designed to selectively conduct the load current; several gain resistors including a first gain resistor of the same resistance type as the first shunt resistor, wherein the first gain resistor is a different resistance type than the other gain resistors of the several gain resistors; and a first switch designed to couple the first shunt resistor to the load in a first state and to disconnect the first shunt resistor from the load in a second state. [2] Circuit according to claim 1, wherein the multiple shunt resistors comprise more than two individually selectable shunt resistors. [3] Circuit according to one of the preceding claims, wherein an integrated circuit comprises at least two of the multiple shunt resistors. [4] Circuit according to claim 3, wherein the integrated circuit comprises an amplifier that is selectively coupled to the first gain resistor. [5] Circuit according to claim 3 or 4, wherein the integrated circuit has a controller configured to control the first switch. [6] Circuit according to one of the preceding claims, wherein a first shunt resistor of the multiple shunt resistors comprises a laminate substrate. [7] Circuit according to claim 6, wherein the laminate substrate is a bismaleimide triazine resin (BT) substrate. [8] Circuit according to one of the preceding claims, comprising several switches configured to configure the circuit for a first current sensing area of ​​the multiple current sensing areas, wherein the multiple switches comprise the first switch. [9] Method for operating a multi-range current sensing circuit, wherein the method comprises: Selective coupling of a first shunt resistor to several shunt resistors to conduct a load current; selective coupling of a node of the first shunt resistor with a first node of a first amplifier; selective coupling of a first gain resistor of several gain resistors with a second input of the first amplifier; selective coupling of a first node of the first gain resistor with an output of the first amplifier; Providing a representation of the load current across a first region at the output of the first amplifier; and wherein the first shunt resistor and the first amplifying resistor have conductive media made of the same material. [10] Method according to claim 9, wherein the first shunt resistor and the first amplification resistor have the same substrate material. [11] Method according to claim 9 or 10, comprising detection such that the representation of the load current approaches an extreme of the first region. [12] Method according to claim 11, isolating the first shunt resistor from conducting the load current and from the first amplifier in response to a detection that the representation of the load current is approaching the extreme of the first region; selective isolation of the first gain resistor from the first amplifier in response to a detection that the representation of the load current approaches the extreme of the first region; and selectively couples a second shunt resistor to conduct the load current and a second gain resistor to the amplifier to detect the load and provide an indication of the load current over a second range. [13] Method according to claim 12, wherein the second region is higher than the first region. [14] Method according to any one of claims 9 to 13, wherein: selectively coupling a node of the first shunt resistor to a first node of a first amplifier and to a first node of a second amplifier; and selective coupling of a first gain resistor of several gain resistors between a second input of the first amplifier and a second input of the second amplifier. [15] Multi-range current sensing circuit comprising: several means for bypassing a load current; a means of providing a representation of the load flow; and several means of providing amplification for the means of providing the representation of the load current. [16] Multi-range current sensing circuit according to claim 15, wherein a conductive material of a first means of the multiple means for bypassing the load current and a conductive material of a first means for providing amplification are a first material. [17] Multi-range current sensing circuit according to claim 16, wherein a conductive material of a second means of the multiple means for bypassing the load current and a conductive material of a second means for providing amplification are a second material. [18] Multi-range current sensing circuit according to claim 16 or 17, wherein a substrate material of the first means of the multiple means for bypassing the load current and a substrate material of the first means for providing an amplification are a first substrate material. [19] Multi-range current sensing circuit according to claim 17 or claims 17 and 18, wherein a substrate material of the second means of the multiple means for bypassing the load current and a substrate material of the second means for providing an amplification are a second substrate material. [20] Multi-range current sensing circuit according to one of claims 15 to 19, wherein the multiple means for shunting the load current, the means for providing the representation of the load current and the multiple means for providing an amplification are configured to provide the representation using at least three resolution ranges.

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