Measurement system

Abstract

To effectively measure current consumption during intermittent operation in a semiconductor integrated circuit.SOLUTION: A first control unit (12) uses a release of a second mode determined by a mode determination circuit (13) as a trigger to control an intermittent operation circuit (1A) to wait for a first predetermined time before operating, and a measuring device (2) measures current consumption of a semiconductor integrated circuit (1) when a second predetermined time shorter than the first predetermined time has elapsed since the release of the second mode.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to measurement systems. [Background technology]

[0002] 2. Description of the Related Art Conventionally, semiconductor integrated circuits have been known that cause component circuits to perform intermittent operations in order to reduce power consumption (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-42012 A

[0004] [overview] In the semiconductor integrated circuit described above, it is necessary to measure the current consumption during intermittent operation and guarantee the product.

[0005] In view of the above circumstances, an object of the present disclosure is to provide a measurement system capable of effectively measuring current consumption during intermittent operation in a semiconductor integrated circuit.

[0006] A measurement system according to one embodiment of the present disclosure includes: An intermittent operation circuit; a mode determination circuit configured to determine a first mode in which the intermittent operation circuit performs an intermittent operation and a second mode in which the intermittent operation circuit is maintained in an operating state; a first control unit configured to control operation of the intermittent operation circuit in accordance with the mode determined by the mode determination circuit; A semiconductor integrated circuit having A measuring device, the first control unit controls the intermittent operation circuit to wait for a first predetermined time before operating, using release of the second mode determined by the mode determination circuit as a trigger; The measurement device is configured to measure the current consumption of the semiconductor integrated circuit when a second predetermined time, which is shorter than the first predetermined time, has elapsed since the second mode was released. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing the configuration of a measurement system according to a first comparative example. [Diagram 2] FIG. 2 is a diagram showing an example of a waveform of a current consumption and a waveform of the current consumption smoothed by an RC filter. [Diagram 3] FIG. 3 is a diagram showing a configuration of an IC according to a second comparative example. [Figure 4] FIG. 4 shows an example of the waveform of the current consumption of an IC in normal operation in the upper part, and an example of the waveform of the current consumption in test mode in the lower part. [Diagram 5] FIG. 5 is a diagram showing a configuration of an IC according to a third comparative example. [Figure 6] FIG. 6 is a diagram showing a configuration of a measurement system according to an exemplary embodiment of the present disclosure. [Figure 7] FIG. 7 is a timing chart showing an example of the operation of the measurement system shown in FIG.

[0008] [Detailed Description] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings.

[0009] <First Comparative Example> Before describing the embodiments of the present disclosure, a comparative example will be described for comparison purposes. Fig. 1 is a diagram showing the configuration of a measurement system 101 according to a first comparative example.

[0010] The measurement system 101 includes an IC (semiconductor integrated circuit) 10, an RC filter 15, and an ammeter 16. The measurement system 101 is a system for measuring the current consumption of the IC 10 that performs intermittent operation. The IC 10 has a power terminal 10A, a ground terminal 10B, and an output terminal 10C as external terminals for establishing an electrical connection with the outside. A power supply voltage Vdd is applied to the power terminal 10A. A ground potential is applied to the ground terminal 10B. An output signal OUT is output from the output terminal 10C. The current consumption of the IC 10 is a current that flows through the power terminal 10A. Since the IC 10 performs intermittent operation, there are an operating current and a standby current as the current consumption. However, if the current consumption is simply measured, the timing of the current consumption and the timing of the measurement cannot be synchronized, and therefore it is not possible to know whether the measured current is an operating current or a standby current.

[0011] Therefore, the measurement system 101 is provided with an RC filter 15. The RC filter 15 has a resistor 15A and a capacitor 15B. A first terminal of the resistor 15A is connected to a first terminal of the capacitor 15B and the power supply terminal 10A. A second terminal of the capacitor 15B is connected to an application terminal of the ground potential. The ammeter 16 is disposed between the application terminal of the power supply voltage Vp and the second terminal of the resistor 15A.

[0012] FIG. 2 shows an example of the waveform of the current consumption Ic and an example of the waveform of the current consumption Ics obtained by smoothing the current consumption Ic by the RC filter 15. The current consumption Ic alternates between an operating current Ic1 and a standby current Ic2. Ic1>Ic2. In the unstable period TA, the behavior of the current consumption Ics is unstable depending on the initial state of the capacitor 15B. After the unstable period TA, the current consumption Ics stabilizes in a stable period TB. In the stable period TB, the current consumption Ics is measured by the ammeter 16. However, the capacitance of the capacitor 15B becomes large due to the smoothing, and the unstable period TA becomes long, which takes time to measure and increases the cost of testing.

[0013] <Second Comparative Example> 3 is a diagram showing a configuration of IC20 according to a second comparative example. IC20 performs intermittent operation and has a first test terminal 20D and a second test terminal 20E in addition to a power terminal 20A, a ground terminal 20B, and an output terminal 20C as external terminals. A first test signal Stst1 is applied to the first test terminal 20D. A second test signal Stst2 is applied to the second test terminal 20E. The first test signal Stst1 is a signal for shifting IC20 to a test mode. The second test signal Stst2 is a signal for switching the current consumption mode of IC20 in the test mode.

[0014] FIG. 4 shows an example of the waveform of the current consumption Ic of IC20 in normal operation in the upper part, and shows an example of the waveform of the current consumption Ic in test mode in the lower part. In normal operation, the current consumption Ic alternates between the operating current Ic1 and the standby current Ic2. When IC20 transitions to the test mode by the first test signal Stst1, the second test signal Stst2 switches between a mode TEST1 in which the operating current Ic1 is fixed and a mode TEST2 in which the standby current Ic2 is fixed. This makes it possible to measure the operating current Ic1 in the mode TEST1 and the standby current Ic2 in the mode TEST2. However, in the second comparative example, there is a problem that the number of external terminals of IC20 increases.

[0015] <Third Comparative Example> FIG. 5 is a diagram showing a configuration of IC30 according to a third comparative example. IC30 has an overvoltage determination circuit 30A. The overvoltage determination circuit 30A is a circuit that determines an overvoltage of the power supply voltage Vdd. When an overvoltage of the power supply voltage Vdd is detected by the overvoltage determination circuit 30A, IC30 transitions to a test mode. In the test mode, IC30 is in an operating current mode for a predetermined period of time and then in a standby current mode. This makes it possible to measure the operating current and the standby current while suppressing the number of external terminals without providing a test terminal as in the second comparative example. However, in the case of the standby current mode, if the overvoltage determination circuit 30A is turned off to reduce current consumption as much as possible, it becomes impossible to detect the release of the overvoltage of the power supply voltage Vdd, and IC30 cannot return to the normal mode from the test mode.

[0016] <Embodiments of the present disclosure> In order to solve the problems in the comparative examples as described above, the following embodiment is implemented. Fig. 6 is a diagram showing a configuration of a measurement system 5 according to an exemplary embodiment of the present disclosure.

[0017] The measurement system 5 includes an IC1 and a measurement device 2. The IC1 includes an oscillation circuit 11, a logic circuit (control unit) 12, a mode determination circuit 13, and a main circuit 14. The IC1 also includes a power supply terminal T1, a ground terminal T2, and an output terminal T3 as external terminals. A power supply voltage Vdd is applied to the power supply terminal T1. A ground potential is applied to the ground terminal T2. The power supply voltage Vdd is supplied to the oscillation circuit 11, the logic circuit 12, the mode determination circuit 13, and the main circuit 14.

[0018] Oscillator circuit 11 generates clock CLK. Mode determination circuit 13 and main circuit 14 constitute intermittent operation circuit 14. Intermittent operation circuit 14 performs intermittent operation. Logic circuit 12 counts clock CLK to control the intermittent operation of intermittent operation circuit 14. Intermittent operation timing is generated by counting clock CLK. In intermittent operation, the on and off states of intermittent operation circuit 1A are alternately repeated. Oscillator circuit 11 and logic circuit 12 operate constantly.

[0019] Mode determination circuit 13 is a circuit that determines the mode. Specifically, mode determination circuit 13 determines between a normal mode (first mode) and a test mode (second mode). In the normal mode, logic circuit 12 causes intermittent operation circuit 14 to perform intermittent operation. The test mode will be described later.

[0020] The mode determination circuit 13 has a comparator 131. The comparator 131 compares the power supply voltage Vdd applied to the power supply terminal T1 with a reference voltage Vref. A comparison output Cout as a comparison result by the comparator 131 is output to the logic circuit 12. When the power supply voltage Vdd is equal to or lower than the reference voltage Vref, the comparator 131 outputs a low-level comparison output Cout indicating a normal mode. When the power supply voltage Vdd exceeds the reference voltage Vref, the power supply voltage Vdd is determined to be an overvoltage, and the comparator 131 outputs a high-level comparison output Cout indicating a test mode. In this way, the comparator 131 determines whether the power supply voltage Vdd is an overvoltage, and determines the mode.

[0021] The main circuit 14 is a circuit having a main function of the IC 20, and is configured as, for example, a magnetic field detection circuit. An output signal OUT is output from the main circuit 14 via an output terminal T3. When the main circuit 14 is a magnetic field detection circuit, the output signal OUT indicates the result of magnetic field detection.

[0022] The measuring device 2 is disposed outside the IC1, and includes a voltage source 21, an ammeter 22, and a control unit 23. The voltage source 21 generates a power supply voltage Vdd. The ammeter 22 is disposed between the output end of the voltage source 21 and a power supply terminal T1. The ammeter 22 detects a consumption current Ic flowing through the power supply terminal T1. The control unit 23 controls the voltage source 21 and the like.

[0023] The ammeter 22 detects the current by using, for example, a Hall element and outputs the result as a voltage signal Vdet. The voltage signal Vdet is acquired by the control unit 23, whereby the consumption current Ic is measured.

[0024] Fig. 7 is a timing chart showing an example of operation of the measurement system 5 configured as above. In Fig. 7, the power supply voltage Vdd, the mode, and the current consumption Ic are shown from the top.

[0025] The power supply voltage Vdd can be a normal voltage Vdd1 or an overvoltage Vdd2 (>Vdd1) depending on the output of the voltage source 21. The normal voltage Vdd1 corresponds to the normal mode (MODE1), and the overvoltage Vdd2 corresponds to the test mode (MODE2).

[0026] When intermittent operation circuit 1A is switched to the on state (ON1 in FIG. 7), mode determination circuit 13 is switched to the on state, and logic circuit 12 acquires comparison output Cout output from comparator 131. When intermittent operation circuit 1A is in the on state, current consumption Ic becomes operating current Ic1. When voltage Vdd is normal voltage Vdd1, comparison output Cout becomes low level and the mode becomes normal mode. When logic circuit 12 confirms that it is in normal mode, it switches intermittent operation circuit 1A to the off state at a first predetermined timing by counting clock CLK (OFF1 in FIG. 7). At this time, current consumption Ic becomes standby current Ic2. Thereafter, logic circuit 12 switches intermittent operation circuit 1A to the on state at a second predetermined timing by counting clock CLK. In normal mode, intermittent operation is performed by repeating such operations.

[0027] In measuring device 2, when the mode is shifted to the test mode, control unit 23 performs control to switch the output of voltage source 21 to overvoltage. As a result, power supply voltage Vdd is switched to overvoltage Vdd2 (timing t1). When logic circuit 12 switches intermittent operation circuit 1A to the on state and acquires comparison output Cout, if it confirms that comparison output Cout is at a high level, that is, that power supply voltage Vdd is overvoltage Vdd2 and that the mode is the test mode, it maintains the on state of intermittent operation circuit 1A. Thereafter, every time logic circuit 12 confirms the test mode by comparison output Cout, it maintains the on state of intermittent operation circuit 1A (ON2 in FIG. 7). In measuring device 2, control unit 23 acquires voltage signal Vdet output from ammeter 22 when a predetermined time T1 has elapsed since switching to overvoltage, and measures current consumption Ic (measurement timing Dt1). As a result, it is possible to measure operating current Ic1 during period ON2 during which intermittent operation circuit 1A is maintained in the on state by the test mode. Note that although in FIG. 7 timing t1 at which power supply voltage Vdd switches to overvoltage Vdd2 coincides with the timing at which intermittent operation circuit 1A switches to the on state, timing t1 may occur before the timing at which intermittent operation circuit 1A switches to the on state.

[0028] In the measuring device 2, when the control unit 23 switches the output of the voltage source 2 from an overvoltage to a normal voltage in order to switch the mode to the normal mode, the power supply voltage Vdd switches to the normal voltage Vdd1 (timing t2). When the logic circuit 12 confirms from the comparison output Cout that the power supply voltage Vdd has switched to the normal voltage Vdd1, that is, that the mode has switched to the normal mode, while the on state of the intermittent operation circuit 1A is maintained by the test mode, the logic circuit 12 switches the intermittent operation circuit 1A to the off state. As a result, the consumption current Ic switches to the standby current Ic2. The logic circuit 12 maintains the off state of the intermittent operation circuit 1A for a predetermined time T2, triggered by the mode switching to the normal mode (release of the test mode), and switches the intermittent operation circuit 1A to the on state after the predetermined time T2 has elapsed. Thereafter, the logic circuit 12 operates as in the normal mode described above, and intermittent operation is performed.

[0029] In the measuring device 2, when a predetermined time T3 has elapsed from timing t2 when the control unit 23 switches the output of the voltage source 2 to the normal voltage, the control unit 23 acquires the voltage signal Vdet output from the ammeter 22 and measures the current consumption Ic (measurement timing Dt2). The predetermined time T3 is shorter than the predetermined time T2, and the measurement timing Dt2 is, for example, immediately before timing t3 when the predetermined time T2 has elapsed. Note that the predetermined time T3 is preferably set longer than the time it takes for the voltage signal Vdet to become stable after the control unit 23 switches the output of the voltage source 2 to the normal voltage.

[0030] According to this embodiment, the operating current Ic1 and the standby current Ic2 can be measured. In order to measure the standby current Ic2, the mode determination circuit 13 is turned off. However, at timing t3 when a predetermined time T2 has elapsed, the mode determination circuit 13 is switched on, so that the intermittent operation in the normal mode can be restored. In addition, since the mode determination circuit 13 is configured as an overvoltage determination circuit, the number of external terminals of IC1 can be reduced.

[0031] If it takes time for the voltage signal Vdet to stabilize, the measurement timing may be changed to Dt2_1 by extending the predetermined time T3 to T3_1, as shown in FIG. 7, and the predetermined time T2 may be extended to T2_1 accordingly.

[0032] Furthermore, mode determination circuit 13 is not limited to performing intermittent operation and may operate constantly, in which case mode determination circuit 13 is not included in intermittent operation circuit 1A.

[0033] <Other> In addition to the above-mentioned embodiment, various technical features disclosed in this specification can be modified in various ways without departing from the spirit of the technical creation. In other words, the above-mentioned embodiment should be considered to be illustrative and not restrictive in all respects, and the technical scope of the present invention should be understood to be not limited to the above-mentioned embodiment, but to include all modifications that fall within the meaning and scope equivalent to the claims. In addition, the embodiments of the present disclosure can be implemented in appropriate combinations.

[0034] <Additional Notes> As described above, the measurement system (5) according to one embodiment of the present disclosure is An intermittent operation circuit (1A); a mode determination circuit (13) configured to determine between a first mode (normal mode) in which the intermittent operation circuit operates intermittently and a second mode (test mode) in which the intermittent operation circuit is maintained in an operating state (on state); a first control unit (12) configured to control the operation of the intermittent operation circuit in accordance with the mode determined by the mode determination circuit; A semiconductor integrated circuit (1) having A measuring device (2), the first control unit controls the intermittent operation circuit to wait for a first predetermined time (T2) before operating, using the release of the second mode determined by the mode determination circuit as a trigger; The measuring device is configured to measure the current consumption of the semiconductor integrated circuit when a second predetermined time (T3) shorter than the first predetermined time has elapsed since the second mode was released (first configuration).

[0035] With this configuration, it is possible to measure the operating current and the standby current during intermittent operation of the semiconductor integrated circuit.

[0036] In the above first configuration, the intermittent operation circuit (1A) may include the mode determination circuit (13) (second configuration).

[0037] In the first or second configuration, the mode determination circuit (13) may have a circuit for determining whether a power supply voltage (Vdd) supplied to the semiconductor integrated circuit is overvoltage (third configuration).

[0038] In the third configuration, the circuit for determining an overvoltage may be a comparator (131) configured to compare the power supply voltage with a reference voltage (fourth configuration).

[0039] Furthermore, in the third or fourth configuration, the measuring device (2) may be configured to include a voltage source (21) for generating the power supply voltage (Vdd), an ammeter (22) for measuring the current consumption, and a second control unit (23) configured to control the output of the voltage source to switch between a normal voltage and the overvoltage and to obtain a detection signal (Vdet) of the current consumption from the ammeter (fifth configuration).

[0040] In addition, in the above fifth configuration, the second predetermined time (T3) may be set to be longer than the time from when the power supply voltage is switched from the overvoltage to the normal voltage until the detection signal becomes stable (sixth configuration). [Industrial Applicability]

[0041] The present disclosure can be used, for example, to measure the current consumption of various semiconductor integrated circuits. [Explanation of symbols]

[0042] 1. IC 1A intermittent operation circuit 2. Measuring Equipment 5. Measurement System 10A power terminal 10B Ground terminal 10C Output terminal 11 Oscillator Circuit 12 Logic Circuits 13 Mode determination circuit 14 Main Circuit 15 RC Filter 15A resistor 15B Capacitor 16 Ammeter 20A power terminal 20B Ground terminal 20C output terminal 20D 1st test terminal 20E 2nd test terminal 21 Voltage Source 22 Ammeter 23 Control Unit 30 IC 30A overvoltage detection circuit 101 Measurement System 131 Comparator T1 power terminal T2 Ground terminal T3 output terminal

Claims

1. An intermittent operation circuit; a mode determination circuit configured to determine a first mode in which the intermittent operation circuit performs an intermittent operation and a second mode in which the intermittent operation circuit is maintained in an operating state; a first control unit configured to control an operation of the intermittent operation circuit in accordance with the mode determined by the mode determination circuit; A semiconductor integrated circuit having A measuring device, the first control unit controls the intermittent operation circuit to wait for a first predetermined time before operating, using release of the second mode determined by the mode determination circuit as a trigger; The measurement device measures the current consumption of the semiconductor integrated circuit when a second predetermined time, which is shorter than the first predetermined time, has elapsed since the second mode was released.

2. The measurement system according to claim 1 , wherein the intermittent operation circuit includes the mode determination circuit.

3. 2. The measurement system according to claim 1, wherein the mode determination circuit includes a circuit for determining an overvoltage of a power supply voltage supplied to the semiconductor integrated circuit.

4. 4. The measurement system of claim 3, wherein the circuit for determining an overvoltage is a comparator configured to compare the power supply voltage with a reference voltage.

5. The measuring device is a voltage source for generating the power supply voltage; an ammeter for measuring the current consumption; a second control unit configured to perform control to switch the output of the voltage source between a normal voltage and the overvoltage and to obtain a detection signal of the current consumption from the ammeter; The measurement system of claim 3 , further comprising:

6. The measurement system according to claim 5 , wherein the second predetermined time is set to be longer than the time it takes for the detection signal to become stable after the power supply voltage is switched from the overvoltage to the normal voltage.

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