Fast transient detection

Abstract

This disclosure relates to fast transient detection. A voltage monitor (VS) or voltage sensing circuit or architecture capable of detecting fast voltage transients. To detect fast voltage transients, a dedicated differential pair is positioned between the point of load (such as a die or other chip, processor, etc.) and the circuitry of the voltage monitor. By connecting the differential pair at the point of load, fast voltage transients can be detected at the load level (e.g., at the point of load) and subsequently used to enable, disable, and / or restart electronic devices, such as dies, chips, processors, or other electronic components or systems.

Description

Technical Field

[0001] This disclosure relates to the detection of fast transients. Background Technology

[0002] Many modern electronic devices (including electronic systems and individual electronic components) have strict power supply operating ranges. When supplied with power outside the proper operating range, these electronic devices may be damaged, malfunction, and / or suffer performance degradation. If the supplied power is outside the proper operating range, some electronic devices may not be able to power on.

[0003] A voltage monitor (sometimes also called a reset integrated circuit, power-down detector, or voltage detector) is a device that monitors and controls the power delivered to electronic devices. Voltage monitors can detect voltage transients, which are undervoltage or overvoltage events. An undervoltage event is a voltage drop or fall below a certain threshold, while an overvoltage event is a voltage surge above a certain threshold. When a voltage monitor detects a voltage transient event, it can assert a signal to enable, disable, or reset another device, such as an electronic device. By doing so, the voltage monitor can prevent performance problems or malfunctions in electronic devices.

[0004] Typical voltage monitors can only detect voltage transients longer than 100 ns. However, fast transient events (such as those lasting less than 100 ns and not detected by voltage monitors) can still damage electronic equipment and negatively impact its performance. Summary of the Invention

[0005] This disclosure provides a voltage monitor capable of detecting and responding to fast voltage transient events. One aspect of this disclosure relates to an apparatus comprising: a voltage monitoring circuit for sensing voltage changes and having a first connection point and a second connection point; and a lead pair connected to a die and coupled to the first and second connection points such that the voltage monitoring circuit can sense a differential voltage associated with an effective supply voltage at the die.

[0006] In some cases, differential voltage includes voltage changes with a duration of less than or equal to 10 nanoseconds.

[0007] In some cases, differential voltage includes voltage changes with a duration of less than or equal to 1 nanosecond.

[0008] In some cases, the lead is connected to the die across resistors and capacitors connected in series.

[0009] In some cases, the lead pair is directly connected to the die.

[0010] In some cases, the lead pair couples the changes in current load on the die to the first connection point and the second connection point.

[0011] In some cases, voltage monitoring circuits include voltage monitors.

[0012] In some cases, the voltage monitoring circuit is configured to include a threshold voltage that can be adjusted in increments of 5 millivolts or less.

[0013] In some cases, the voltage monitoring circuit includes a reset output that outputs a reset signal based on the differential voltage sensed by the voltage monitoring circuit.

[0014] In some cases, the device includes a printed circuit board, an integrated circuit package, or a system-on-a-chip.

[0015] In some cases, voltage monitoring circuitry includes a voltage monitor.

[0016] In some cases, the voltage monitor also includes a voltage regulator configured to supply power to the die.

[0017] In some cases, the voltage monitor is configured to sense a differential voltage associated with the effective supply voltage at the die and pass that differential voltage to the voltage regulator.

[0018] In some cases, the voltage regulator compares the differential voltage with a reference voltage to determine the voltage change.

[0019] In some cases, the regulator is configured to send a die enable signal to enable, disable, or reset the die.

[0020] In some cases, the voltage monitor is part of the die.

[0021] In some cases, the voltage monitor is configured to sense a differential voltage associated with the effective power supply voltage at the PCB on which the die is mounted.

[0022] In some cases, the voltage monitor is configured to pass a differential voltage associated with the effective supply voltage at the PCB to the voltage regulator.

[0023] In some cases, the voltage regulator compares a differential voltage associated with the effective supply voltage at the PCB with a reference voltage to determine voltage changes.

[0024] In some cases, the regulator is configured to send a die enable signal to enable, disable, or reset the die after determining that the voltage change meets a threshold. Attached Figure Description

[0025] Figure 1 This is a block diagram illustrating example voltage drops in the power signal aspect according to various aspects of this disclosure.

[0026] Figure 2 This is a block diagram of an example voltage regulator that provides power to an integrated circuit according to various aspects of this disclosure.

[0027] Figure 3 These are block diagrams of example voltage monitors and integrated circuits based on various aspects of this disclosure.

[0028] Figure 4 This is a block diagram of an example voltage monitor for monitoring power within an integrated circuit according to various aspects of this disclosure.

[0029] Figure 5 This is a block diagram of components of a voltage monitor and voltage regulator according to various aspects of this disclosure. Detailed Implementation

[0030] This disclosure provides a voltage monitor (VS) or voltage sensing circuit or architecture capable of detecting fast voltage transients. To detect fast voltage transients, a dedicated differential pair is positioned between the point-of-load (PoL) (such as a die or other chip, processor, etc.) and the voltage monitor's circuitry. By connecting the differential pair at the point-of-load, fast voltage transients can be detected at the load level (e.g., at the point-of-load) and subsequently used for, for example, enabling, disabling, and / or restarting electronic devices, such as dies, chips, processors, or other electronic components or systems.

[0031] Figure 1 An example transient event triggered by a voltage drop of 103 (i.e., a decrease in voltage) is shown. Figure 1 The voltage level of the power signal 101 delivered to the electronic device during time period t is shown. Before time t1, the voltage of the power signal 101 is V2. However, at time t1, the voltage of the power signal 101 begins to drop, and at time t2, the voltage of the power signal 101 may drop below a threshold voltage (shown as V1). When the threshold V1 is crossed, a transient event can be considered to have occurred. At time t3, when the voltage of the power signal 101 exceeds the threshold V1, the transient event can be considered to have ended. The voltage of the power signal 101 returns to V2 at time t4. The voltage drop can be defined by its width (shown by line 107) and its "amplitude" (i.e., the maximum decrease in the voltage value of the signal over the width of the voltage drop).

[0032] Transient events may also occur when a power signal surge, such as power signal 101, exceeds the threshold voltage. For example, and as... Figure 1As further shown, if the power signal 101 exceeds the upper threshold voltage (shown as V3), a transient event can be considered to have occurred. Therefore, transient events can be caused by power surges and power reductions.

[0033] As used in this paper, a fast transient event can be considered a transient event when the voltage of power signal 101 remains below the threshold for less than 100 ns. Continuing... Figure 1 The example shown can be used to determine whether a transient event is a fast transient event by subtracting time t2 from t3. If the resulting value is less than 100 ns, the transient event shown, caused by a voltage drop, can be considered a fast transient event. Similarly, if the power signal 101 is held above the upper threshold voltage V3 for less than 100 ns (i.e., exceeding V3 for less than 100 ns and then falling below V3), the transient event caused by a surge can be considered a fast transient event.

[0034] Figure 2 A typical VR 220 is shown connected to an integrated circuit (IC) 250 via a power delivery network 200 (PDN). IC 250 includes a printed circuit board (PCB) 251, a package (Pkg) 252, and a die 253. PDN 200 includes circuitry 211 within PCB 251, circuitry 213 within Pkg 252, and circuitry 215 within die 253. The circuits shown by 211, 213, and 215 are merely examples intended to represent RLC networks typically present in the PCB, Pkg, and die, respectively. More or fewer components may be present in the same or different configurations than those shown in circuits 211, 213, and 215. Although IC 250 is shown as comprising a single PCB 251, Pkg 252, and die 253, IC 250 may include any number of dies, packages, PCBs, and other components (e.g., transistors, resistors, capacitors, inductors, chips, processors, etc.) and circuitry found in integrated circuits. Furthermore, although IC 250 is shown, VR 220 can be connected to printed circuit boards and / or on-chip systems.

[0035] like Figure 2As further shown, VR 220 can be connected to PDN 200 via power line 292. Although not shown, VR 220 may include or be connected to one or more transistors, such as field-effect transistors (FETs) or metal-oxide-semiconductor FETs (MOSFETs), for controlling the voltage output by VR 220, for example, by increasing or decreasing the output voltage to maintain a consistent output voltage. Although VR 220 is shown as being external to IC 250, in some implementations, VR 220 may be internal to the IC. In such implementations, PDN 200 may also be entirely within IC 250.

[0036] PDN 200 carries the power signal from VR 220 to load point 216 in die 253 via power line 292. As the power signal is transmitted across the PDN to load point 216, RLC components or combinations thereof within circuits 211, 213, and 215 can act as high-frequency filters, filtering out high-frequency transients at the PCB or package level. Furthermore, because the current (I) of the power signal encounters resistance (R) from the RLC components and other such circuitry as it travels through PDN 200 to load point 216, the RLC components may cause a current reduction (IR reduction). As used herein, unless otherwise stated, resistance (R) is not limited to the resistance of a resistor, but refers to the resistance encountered by the current as it travels through the PDN (such as PDN 200).

[0037] A decrease in IR can lead to a loss of efficiency in power delivery. At this point, the reduced current may be dissipated (e.g., as heat loss) rather than being delivered to the intended destination (e.g., PoL). Therefore, power delivery is inefficient, which can increase operating costs, waste money, etc.

[0038] The IR drop introduced by the RLC components in PCB 251, Pkg 252, and / or die 253 may also slow down the detection of transient events by the voltage monitor, because the transient event must propagate through the PCB and the circuitry connecting the PCB to the voltage monitor before it can be detected. At this point, the voltage monitor typically monitors voltage transients below the PCB level and is connected to the PDN 200 via the PCB. Therefore, the transient event may strike the load point 216 before it has propagated to the voltage monitor and / or before the voltage monitor has time to act on the detected transient event. Furthermore, IR drops occurring after PCB 251 (such as in Pkg 252 and / or die 253) may not be detected.

[0039] As described herein, the disclosed technology's VS solves filtering by implementing differential remote voltage sensing at or near the load point. By detecting the differential remote voltage at the load point, the effects of fast transient filtering that occurs during sensing at the PCB or package level can be reduced or eliminated. Furthermore, by routing differential lead pairs from the die or other load point to the VS, the VS allows for adjustment of the VR voltage trigger level in small increments. Further, this technology enables the monitoring of multiple power rails on the PCB, in the package, or within the die.

[0040] Another aspect of the disclosed technology is to sense the effective supply voltage as close as possible to the load point, or if possible, directly from the load point. In this case, VS can be integrated into the die or other such components to minimize the propagation time of transients to VS. This will compensate for most of the current reduction (IR reduction) that occurs on the PCB, in the package, and possibly on the die.

[0041] The technique described in this article also advantageously allows the VS to detect voltage drops that cause transient events, including fast transient events. Detecting voltage drops enables the VS to monitor voltage rails within the system (e.g., PCB, package, etc.) to detect such drops and send alarms that can be used to reset the system, processor, etc. As explained earlier, a fault that generates an alarm during a fast transient can cause the system to experience performance problems such as power loss (e.g., causing operation at a lower speed than expected), malfunction (e.g., operating differently than expected or shutting down completely), or damage. This technique can mitigate or prevent these types of events.

[0042] Figure 3 An example voltage monitor 325, including VR 320 and VM 322, is shown within integrated circuit 350. Although VS325 is shown separate from the other components of the IC shown, including PCB 351, Pkg 352, and die 353, VS can be integrated into these components. For example, VS 320 can be mounted to PCB 351 or integrated into die 353. Although IC 250 is shown as including a single PCB 351, Pkg 352, and die 353, IC 350 can include any number of dies, packages, PCBs, and other components (e.g., transistors, resistors, capacitors, inductors, chips, processors, etc.) and circuitry found in integrated circuits. By positioning VS 325 within IC 350, the propagation delay experienced by typical voltage monitors is avoided.

[0043] although Figure 3An example VS 325 including VR 320 is shown. However, in some examples, VR 320 may be a separate component from VS 325. In this case, VR 320 can be connected to VM 322 via an external connection between VS 325 and VR 320.

[0044] In operation, VR 320, which can be compared to VR 220, delivers power to the load point (not shown) in die 353. VM 322 detects the voltage change of the power delivered to the PoL by VR 320 relative to a reference power. Based on these detected differences that VM 322 can provide to VR, VR can adjust (i.e., increase or decrease) the amount of voltage supplied to the PoL. In the event that the power supplied to the PoL moves outside a predetermined operating range (such as due to transient events, including fast transient events), VS 325 (such as via VR 320) can activate a signal on reset line 391 to enable, disable, or reset die 353. In other cases, other component portions of VM 322 or VS 325 can activate signals to enable, disable, or reset die 353. In these examples, reset line 391 can travel from other component portions of VM 322 or VS 325.

[0045] As shown, VR 320 supplies power to other components of integrated circuit 350 (including any components within PCB 351, PCB 352, and die 353 that can be compared with PCB 251, PCB 252, and die 253, respectively) via power line 392. Although not shown, VR 320 can supply power to any number of components in integrated circuit 350 (including components on PCB 351, PCB 352, and die 353).

[0046] like Figure 3 As shown, VM 322 is configured to receive differential voltage measurements acquired at PCB 351 and die 353. At this point, the differential voltage measurement V1 acquired at PCB 351 is provided to VM 322 via a connection indicated by line 371. Similarly, the differential voltage measurement V2 acquired at die 353 is provided to VM 322 via a connection indicated by line 372. Although... Figure 3 The differential voltage measurement V1 captured at PCB 351 is shown, but V1 can be captured at Pkg 352 or before PCB 351. In some embodiments, a third differential voltage measurement can be captured at Pkg 352, in which case three differential voltage measurements can be provided to VM322.

[0047] Figure 4Example connection points are shown for capturing differential voltage measurements V1 and V2 in PCB 351 and die 353, respectively. At these points, differential voltage measurement V1 can be captured at connection points 451a and 451b across capacitor 317 in PCB circuit 311. Similarly, differential voltage measurement V2 can be captured at connection points 453a and 453b across capacitor 318 and resistor 319 connected in series in die circuit 315. Differential voltage measurement V2 is a differential voltage measurement across the load point within die 353. Figure 4 The connection points shown are merely examples. Any connection point that captures the voltage on a power line (such as power line 392) and a ground line (such as ground line 393) can be used to measure differential voltage.

[0048] Measurements corresponding to V1 and V2 can be transmitted back to voltage monitor 322 via connections. For example, measurements associated with voltage measurements V1 captured at points 451a and 451b can be transmitted to VM 322 via lines 551a and 551b, respectively. Similarly, measurements associated with voltage measurements V1 captured at points 453a and 453b can be transmitted to VM 322 via lines 553a and 553b, respectively.

[0049] Figure 5 The connection between the differential voltage measurement and the differential amplifier within VM 322 is shown. At this point, lines 551a and 551b are connected to differential amplifier (DA) 561, and lines 553a and 553b are connected to DA 563. Differential amplifiers 561 and 563 convert the differential voltage measurement into a single-ended ground reference signal. The differential voltage measurement is the difference between the voltages on the lines input to the DA. For example, DA 561 can determine the differential voltage between the voltages on lines 551a and 551b, corresponding to the voltage at PCB 351. Similarly, DA 563 determines the differential voltage between the voltages on lines 553a and 553b, corresponding to the voltage at die 353.

[0050] The differential voltage output by DA 561 and 563 can be boosted or attenuated depending on the gain introduced by the DA. In this respect, DA 561 and 563 can provide a gain value to the differential voltage before the differential voltage is output on lines 571 and 573, respectively.

[0051] The differential voltages output from DAs 561 and 563 on lines 571 and 573, respectively, can be input into a voltage divider formed by resistor pairs. For example, line 571 carrying the differential voltage from DA 561 can be input into a voltage divider 586 formed by resistors 581 and 582 connected in parallel, where resistor 582 is connected to ground 585. Similarly, line 537 can be input into a voltage divider 586 formed by resistors 583 and 584 connected in parallel, where resistor 584 is connected to ground 585. Voltage dividers 586 and 587 can attenuate the differential voltage value based on the resistor values ​​used. In some cases, the VM 322 may not include a voltage divider.

[0052] Refer back Figure 3 VM 322 can be connected to VR 320 via a connection shown as line 323. VM 322 can transmit differential voltage to VR 320 via this connection. For example, and as shown... Figure 5 As shown, the differential voltage from DA 561 can be passed to the input of operational amplifier 565 via line 591. Similarly, the differential voltage from DA 563 can be passed to the input of operational amplifier 567 via line 593.

[0053] Each operational amplifier 565 and 567 can compare its received differential voltage with a reference voltage received via lines 592 and 594, respectively. The reference voltage is a predetermined value to which the differential voltage is compared. The threshold voltage can be adjusted in increments of 5 millivolts or more or less. If the differential voltage falls below the predetermined value, a transient event may have occurred. In some cases, when the differential voltage exceeds the reference voltage, it can be determined that a transient event has occurred.

[0054] The output from the operational amplifier can be sent to other circuitry or processes via lines 575 and 577, as shown in box 567. Other circuitry or processor 567 can determine whether to enable, disable, or reset die 353 based on the output of the operational amplifier.

[0055] Although the techniques described herein have been illustrated with reference to specific embodiments, it should be understood that these embodiments merely demonstrate the principles and applications of the technology. Therefore, it should be understood that various modifications can be made to the illustrative embodiments, and other arrangements can be devised, without departing from the spirit and scope of the technology as defined by the appended claims.

[0056] Most of the foregoing alternative examples are not mutually exclusive, but can be implemented in various combinations to achieve unique advantages. Since these and other variations and combinations of the features discussed above can be utilized without departing from the subject matter defined by the claims, the foregoing description of the embodiments should be viewed in an illustrative manner rather than in a restrictive manner as defined by the claims. As an example, the preceding operations need not be performed in the exact order described above. Instead, the various steps can be processed in different orders, such as in reverse order or simultaneously. Steps may also be omitted unless otherwise stated. Furthermore, the examples described herein and the phrases such as "such as," "comprising," etc., should not be construed as limiting the subject matter of the claims to specific examples; rather, these examples are intended to illustrate only one of many possible embodiments. Furthermore, the same reference numerals in different figures may identify the same or similar elements.

Claims

1. An apparatus for detecting fast transients, comprising: A voltage monitoring circuit for sensing voltage changes and having a first connection point and a second connection point; as well as A lead pair, the lead pair being connected to the die and coupled to the first connection point and the second connection point at the load point in the die, such that the voltage monitoring circuit can sense a differential voltage across the load point, the differential voltage being associated with an effective supply voltage at the die, wherein the differential voltage includes a voltage change with a duration of less than 100 nanoseconds, and wherein the duration is either a continuous period of time during which the differential voltage is below a low threshold voltage or a continuous period of time during which the differential voltage is above a high threshold voltage.

2. The apparatus of claim 1, wherein the duration is less than or equal to 10 nanoseconds.

3. The apparatus of claim 1, wherein the duration is less than or equal to 1 nanosecond.

4. The apparatus of claim 1, wherein the lead pair is connected to the die across a series-connected resistor and capacitor.

5. The apparatus of claim 1, wherein the lead pair is directly connected to the die.

6. The apparatus of claim 4, wherein the lead pair couples the change in current load on the die to the first connection point and the second connection point.

7. The apparatus of claim 1, wherein the voltage monitoring circuit includes a voltage monitor.

8. The apparatus of claim 1, wherein the low threshold voltage or the high threshold voltage is adjustable in increments of 5 millivolts or less.

9. The apparatus of claim 1, further comprising a reset output, the reset output being based on a differential voltage output reset signal sensed by the voltage monitoring circuit.

10. The apparatus of claim 1, wherein the apparatus comprises one of a printed circuit board, an integrated circuit package, or a system-on-a-chip.

11. The apparatus of claim 1, wherein the voltage monitoring circuit includes a voltage monitor, and the voltage monitor includes a voltage sensor.

12. The apparatus of claim 11, wherein the voltage monitor further comprises a voltage regulator configured to provide power to the die.

13. The apparatus of claim 12, wherein the voltage monitor is configured to sense a differential voltage associated with an effective power supply voltage at the die and to pass the differential voltage to the voltage regulator.

14. The apparatus of claim 13, wherein the voltage regulator compares the differential voltage with the low threshold voltage or the high threshold voltage to determine the voltage change.

15. The apparatus of claim 14, wherein the voltage regulator is configured to send an enable signal to the die to enable, disable, or reset the die.

16. The apparatus of claim 12, wherein the voltage monitor is part of the die.

17. The apparatus of claim 12, wherein the voltage monitor is configured to sense the differential voltage associated with an effective power supply voltage at a PCB on which the die is mounted.

18. The apparatus of claim 17, wherein the voltage monitor is configured to pass a differential voltage associated with the effective power supply voltage at the PCB to the voltage regulator.

19. The apparatus of claim 17, wherein the voltage regulator compares the differential voltage associated with the effective power supply voltage at the PCB with the low threshold voltage or the high threshold voltage to determine the voltage change.

20. The apparatus of claim 19, wherein the voltage regulator is configured to, after determining that the voltage change meets a threshold, send an enable signal to the die to enable, disable, or reset the die.

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