Switching regulator, method for sensing ready state of driver of switching regulator, multiphase switching regulator

Abstract

The invention relates to a switching regulator, a method for sensing a ready state of a driver of the switching regulator, and a multi-phase switching regulator. The switching regulator includes a driver having a driver wake-up circuit configured to report a readiness state of the driver for operation during a start-up period. The driver wake-up circuit may operate during startup by temporarily drawing power from a power supply of the controller until the power supply of the driver has reached a level sufficient to power the driver wake-up circuit. The driver wake-up circuit is configured to communicate a state of a power supply of the driver through a pin typically used to communicate temperature during startup. Accordingly, the disclosed driver may deliver a state during startup without the need for additional pins, and consumes very little additional power since the circuit is automatically disconnected after startup.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 506,604, filed on June 7, 2023, which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure relates to power electronics and, more particularly, to switching regulators configured to provide a regulated voltage to rail(s). Background Art

[0004] For high power requirements (for example, for computing V CORE For applications such as power supply, a switching regulator may be desirable due to its ability to efficiently provide a regulated voltage at high currents. A switching regulator may include a high power switch configured to alternately charge and discharge an inductor. The high power switch may be switched at a duty cycle that may be increased or decreased to control a direct current (DC) voltage at the output of the switching regulator. Therefore, the switching regulator includes a controller configured to control the duty cycle of a switching signal to provide a constant output voltage when the load state changes. The controller is a low power device, while the switch is a high power device. Therefore, the voltage regulator includes a driver configured to drive the high power switch based on a low power switching signal from the controller. In some embodiments, the driver and the switch are integrated together in the device. Summary of the invention

[0005] The driver and controller may operate based on power from different power supplies, which may start up differently. A startup period before switching begins allows both power supplies to stabilize. This startup period may be longer than desired because the driver cannot communicate the status of its power supply until a communication channel is established between the controller and the driver. There is a need for the driver to communicate its status more quickly in a manner that does not require additional pins and / or excess power.

[0006] Thus, in some aspects, the technology described herein relates to a switching regulator comprising: a driver coupled to a driver power supply; a controller coupled to the controller power supply and configured to couple the controller power supply to the driver during a startup period; and a driver wake-up circuit included in the driver that receives power from the controller power supply during the startup period to control a temperature monitoring pin of the driver based on a driver supply voltage of the driver power supply.

[0007] In some aspects, the technology described herein relates to a method for sensing a ready state of a driver in a switching regulator, the method comprising: starting a controller power supply of a controller for the switching regulator; enabling a driver power supply of the driver of the switching regulator; coupling the controller power supply to a driver wake-up circuit of the driver; coupling the controller power supply to a gate of an output transistor when a driver supply voltage of the driver power supply is less than a controller supply voltage of the controller power supply; configuring the output transistor to an on state using power from the controller power supply to pull down a temperature monitoring pin of the driver to a low voltage level when the driver supply voltage is less than the controller supply voltage; decoupling the controller power supply from the gate of the output transistor when the driver supply voltage is greater than or equal to the controller supply voltage; configuring the output transistor to an off state using power from the driver power supply to open the temperature monitoring pin when the driver supply voltage is greater than or equal to the controller supply voltage; and sensing the ready state of the driver based on the state of the temperature monitoring pin.

[0008] In some aspects, the technology described herein relates to a multi-phase switching regulator, which includes: a controller, which is configured to receive power from a first power supply at a first power supply pin and couple the power from the first power supply to a driver turn-on pin; a first driver, which is coupled to the driver turn-on pin at a first driver wake-up pin and to a second power supply at a second power supply pin, and the first driver is configured to: receive power from the first power supply and block power from the second power supply when the second power supply voltage is less than the first power supply voltage; and a second driver, which is coupled to the driver turn-on pin at a second driver wake-up pin and to a third power supply at a third power supply pin, and the second driver is configured to: receive power from the first power supply and block power from the third power supply when the third power supply voltage is less than the first power supply voltage.

[0009] In some aspects, the technology described herein relates to a switching regulator comprising: a driver coupled to a driver power supply; a controller coupled to the controller power supply and configured to couple the controller power supply to the driver during a startup period; and a driver wake-up circuit included in the driver, receiving power from the controller power supply during the startup period to control a temperature monitoring pin of the driver based on a driver supply voltage of the driver power supply.

[0010] In some aspects, the technology described herein relates to a method for sensing a ready state of a driver in a switching regulator, the method comprising: starting a controller power supply of a controller for the switching regulator; coupling the controller power supply to the driver of the switching regulator; enabling a driver power supply of the driver of the switching regulator; comparing a driver supply voltage of the driver power supply with a controller supply voltage of the controller power supply; using the larger of the driver supply voltage and the controller supply voltage to power a driver wake-up circuit of the driver; using the driver wake-up circuit to compare the driver supply voltage with a power-on reset threshold; when the driver supply voltage is less than the power-on reset threshold, using the driver wake-up circuit to generate a short circuit state at a temperature monitoring pin of the driver; when the driver supply voltage is greater than the power-on reset threshold, using the driver wake-up circuit to generate an open circuit state at the temperature monitoring pin of the driver; and sensing the ready state of the driver based on the short circuit state or the open circuit state of the temperature monitoring pin.

[0011] In some aspects, the technology described herein relates to a multi-phase switching regulator, which includes: a controller, which is configured to receive power from a first power supply at a first power supply pin and couple the power from the first power supply to a driver turn-on pin; a first driver, which is coupled to the driver turn-on pin at a first driver wake-up pin and to a second power supply at a second power supply pin, and the first driver is configured to: receive power from the first power supply and block power from the second power supply when the second power supply voltage is less than the first power supply voltage; and a second driver, which is coupled to the driver turn-on pin at a second driver wake-up pin and to a third power supply at a third power supply pin, and the second driver is configured to: receive power from the first power supply and block power from the third power supply when the third power supply voltage is less than the first power supply voltage.

[0012] The foregoing illustrative summary, as well as other exemplary objects and / or advantages of the present disclosure, and implementations are further explained in the following detailed description and its accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic block diagram of a multi-phase switching regulator according to a possible implementation of the present disclosure.

[0014] Figure 2 is a schematic diagram of a high-power portion of an integrated MOSFET driver according to a possible implementation of the present disclosure.

[0015] Figure 3is a graph illustrating startup of a power supply of a switching regulator according to a possible implementation of the present disclosure.

[0016] Figure 4 is a schematic block diagram of a switching regulator with a driver wake-up circuit according to a possible implementation of the present disclosure.

[0017] Figure 5A A driver wake-up circuit in a driver not ready state according to a possible implementation of the present invention is shown.

[0018] Figure 5B A driver wake-up circuit in a driver ready state according to a possible implementation of the present invention is shown.

[0019] Figure 5C A driver wake-up circuit in an operational state is shown according to a possible implementation of the present invention.

[0020] Figure 6 is a flow chart of a method for sensing a ready state of a driver in a switching regulator according to a possible implementation of the present disclosure.

[0021] Figure 7 It shows that Figure 6 A flow chart of a method for using a method of sensing temperature monitoring pins together.

[0022] The components in the drawings are not necessarily drawn to scale relative to each other. Like reference numerals indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0023] A switching regulator may include a controller and one or more drivers. The one or more drivers may be powered for operation by one or more power supplies, which may be different from the power supply used to power the controller. The driver cannot operate properly until the power supply supplying the driver reaches a sufficient voltage. For example, the driver may not be able to provide a stable feedback signal to the controller until the power supply of the driver is at a sufficiently high voltage. Therefore, the controller may wait for all drivers to be ready before starting operation (i.e., regulation). This waiting time may be longer than required when the communication used for reporting requires that the power supply of the driver is completely stable. Adding a dedicated communication channel to report the ready state of the driver may have technical problems of consuming too much power and / or requiring additional pins. A driver that uses a driver wake-up circuit to solve these technical problems is disclosed, which driver wake-up circuit can report the ready state of an existing pin used for another purpose after startup, and can temporarily draw power from the controller's power supply until the driver's own power supply reaches a sufficient voltage.

[0024] Figure 1is a schematic block diagram of a multiphase switching regulator according to a possible implementation of the present disclosure. The multiphase switching regulator 100 may include multiple rails configured to output a regulated voltage. As shown, the multiphase switching regulator 100 includes a first rail 131 and a second rail 132. Each rail may include multiple phases that are combined to provide the current required to drive a load coupled to the rail, even if the load changes. In a possible implementation, the phases of the rail may be activated or deactivated based on the power demand of the load. Although each phase may be identical, each rail may include a different number of phases to provide the power (e.g., current) required by the rail. As shown in FIG. Figure 1 As shown, the first rail 131 includes four phases, while the second rail 132 includes two phases.

[0025] The multi-phase switching regulator 100 includes a controller 110. The controller 110 can be configured by software instructions to configure the controller to perform the operation of the switching regulator. For example, during regulation, the controller 110 can be configured to transmit a switching signal (i.e., a PWM signal) at a plurality of pulse width modulation (PWM) outputs (e.g., PWM1, PWM2, PWM3, PWM4, PWM1A, PWM2A), wherein one PWM output is used for each phase in a plurality of phases. Also during regulation, the controller 110 can be configured to monitor the operation of the phases. For example, the controller 110 can receive temperature signals from all phases at a temperature sensing pin (i.e., TSENSE) via a temperature bus 160. When the temperature signal indicates that one or more phases are above a maximum temperature, the controller 110 can be configured to send a signal via an enable bus 150 to deactivate these phases. The controller 110 includes a driver on pin (i.e., DRON) coupled to the enable bus 150. The DRON pin may be electrically coupled to a first power source 101 (ie, controller power source) that supplies power to the controller 110 via an enable transistor 111 (ie, Q1 ) of the controller 110 .

[0026] Each phase may include a driver and a filter 130. Figure 1As shown, the first rail 131 includes a first driver 121, a second driver 122, a third driver 123, and a fourth driver 124, while the second rail 132 includes a fifth driver 125 and a sixth driver 126. Each driver may include two high-power switches in a half-bridge configuration. Each high-power switch may be a transistor, such as a metal oxide semiconductor field effect transistor (i.e., MOSFET). Each driver may also include a drive circuit configured to drive the high-power MOSFET on and off according to a PWM signal received at a PWM pin of the driver. The switch and the gate drive circuit may be integrated together in a device (e.g., an integrated circuit (IC)) referred to as an integrated MOSFET driver (i.e., DrMOS). Although the driver of the present disclosure is not limited to a DrMOS specific implementation, this specific implementation will be assumed below. Therefore, the terms "driver" and "DrMOS" are used interchangeably.

[0027] Figure 2 Schematic diagram of a high power section 210 of a DrMOS for regulating the phases of a multi-phase switching regulator 100. The high power section 210 includes a high side transistor (e.g., a high side MOSFET 211) coupled between a switch node pin 202 of a driver and a driver power supply 203. The high power section 210 also includes a low side transistor (e.g., a low side MOSFET 212) coupled between a switch node pin 202 of the driver and a ground 204. The high power section 210 also includes a gate driver circuit 215, which is configured to switch a high side MOSFET (i.e., HS-FET) and a low side MOSFET (i.e., LS-FET) according to a PWM signal received at a PWM pin 201 of the driver.

[0028] Return to Figure 1, the drivers of the first rail 131 may be coupled to the second power supply 102 (i.e., the driver power supply) of the multi-phase switching regulator 100. The second power supply 102 may be configured to output a driver power supply voltage (VCC2) that is different from the controller power supply voltage (i.e., VCC1) output by the first power supply 101. For example, VCC2 may be a voltage (e.g., 5 volts) higher than VCC1 (e.g., 3.3 volts). In one possible implementation, the drivers of the multi-phase switching regulator 100 are all coupled to the same power supply. In another possible implementation, the drivers of the multi-phase switching regulator 100 are coupled to different power supplies. For example, as shown, the first driver 121, the second driver 122, the third driver 123, and the fourth driver 124 (i.e., the drivers of the first rail 131) may be coupled to the second power supply 102, while the fifth driver 125 and the sixth driver 126 (i.e., the drivers of the second rail 132) may be coupled to the third power supply 103. The second power supply 102 and the third power supply 103 may be configured to output the same driver power supply voltage (VCC2). This configuration may be advantageous when one power source is insufficient to power all of the drives based on the location and / or availability of the power source relative to the multiple drives.

[0029] In a possible implementation, the controller 110 and the driver may communicate using synchronous serial communication over the communication bus 140. Thus, the communication bus 140 may include a data line (ie, DB1) configured to carry digital packets and a clock line (ie, DB2) configured to carry a digital clock signal.

[0030] The drivers of the multiphase switching regulator 100 are switched by PWM signals from the PWM pins of the controller during regulation, but before regulation can begin, each of the power supplies in the multiphase switching regulator 100 must be at an appropriate operating voltage. Otherwise, a fault (e.g., a pass-through state) may occur. The fault may cause damage to the multiphase switching regulator 100 and / or devices coupled to the multiphase switching regulator 100, particularly in high power environments. To prevent a fault from occurring, the controller 110 may be configured to wait until all drivers are fully functional before starting regulation. Without communicating with the driver, it is impossible to know exactly when the driver is fully functional. However, communication with the driver via the communication bus 140 cannot be established until the driver is fully functional. Therefore, the controller may be configured to wait for a startup period longer than required to ensure that the driver has enough time to become fully functional before establishing communication via the communication bus 140.

[0031] The disclosed system and method can reduce the startup period of the multi-phase switching regulator 100 by establishing a means for transmitting the ready state of the driver to the controller when no communication bus 140 exists or before communication through the communication bus 140 has been established. In other words, the driver can transmit its ready state without using the communication bus, and the controller can immediately respond to the driver with the ready state by configuring it to be in an operating mode. The driver in the operating mode can be configured to (i) communicate with the driver through the communication bus 140, (ii) switch the high-side MOSFET 211 and the low-side MOSFET 212 according to the PWM signal received at the PWM pin, and / or (iii) report the temperature to the controller at the temperature monitoring pin. The driver can be configured to be in the operating mode after operating in the startup mode.

[0032] Figure 3 3 is a graph showing the startup of a power supply of a switching regulator according to a possible implementation of the present disclosure. At activation time 310, a controller supply voltage 301 of a controller power supply increases from zero voltage to a controller power ready voltage 380 over a controller startup period 350. When the controller power supply reaches the controller power ready voltage 380, the controller power supply is ready at a controller ready time 320. Prior to the controller ready time 320, the controller may not be fully functional (i.e., not ready).

[0033] When the controller power ready voltage 380 is reached, the controller may configure the enable transistor 111 to be in an on state so that a driver wake-up signal corresponding to the controller power ready voltage 380 is transmitted to the driver through the enable bus 150. The relatively high voltage level of the driver wake-up signal may activate (i.e., turn on) the driver power supply. At the controller ready time 320, the driver power supply generates the driver supply voltage 302. The driver supply voltage 302 increases from zero voltage at the controller ready time 320 to the driver power ready voltage 390 over the driver startup period 360. When the driver power supply reaches the driver power ready voltage 390, the driver power supply is ready at the driver ready time 340. Before the driver ready time 340, the driver may not be fully functional (i.e., not ready).

[0034] During the driver startup period 360, there is a crossover time 330 where the driver supply voltage 302 becomes greater than the controller supply voltage 301. Before the crossover time 330, the driver supply may not be able to provide the power (e.g., voltage) necessary to communicate a ready state to the controller, and after the crossover time 330, the driver supply may be able to provide the power (e.g., voltage) necessary to communicate a ready state to the controller.

[0035] At driver ready time 340, the driver reaches driver supply ready voltage 390. At this point, operation period 375 may begin. The controller and driver of the switching regulator may operate in a startup mode during startup period 370, and the controller and driver of the switching regulator may operate in an operation mode during operation period 375.

[0036] Figure 4 4 is a schematic block diagram of a switching regulator with a driver wake-up circuit according to a possible specific implementation of the present disclosure. The switching regulator 400 includes a controller 410, which is powered by a controller power supply 411 to implement electrical functions. The controller 410 includes an enable transistor 412 (Q3), which can be configured to be in an on state when the controller power supply 411 is ready. For example, when the controller power supply 411 is at a voltage (i.e., V CON ), the controller power supply 411 is ready.

[0037] When the controller is activated, it can be configured to be in a startup mode. In the startup mode, the temperature sensing pin 415 (ie, T SENSE ) can be coupled (e.g., by switch 414) to the ready detection circuit 401 and decoupled from the temperature monitoring circuit 409. In other words, in the startup mode, the controller 410 can be configured to sense the ready state of the driver 430 by receiving a signal from the temperature bus 160 at the temperature sensing pin 415. Sensing the ready state of the driver can temporarily replace sensing the temperature reported by the driver. Therefore, in the startup mode, the temperature monitoring circuit 409 can be decoupled from the temperature sensing pin 415 (by switch 414).

[0038] The switching regulator 400 includes a driver 430, which is powered by a driver power supply 421 to implement electrical functions. In a possible specific implementation, the driver power supply 421 is activated at the same time as the controller power supply 411 is activated. In another possible specific implementation, the driver power supply 421 is activated after the controller power supply 411 is activated. For example, the driver power supply 421 may be activated based on a driver wake-up signal transmitted to a driver wake-up pin 432 of the driver through the enable bus 150.

[0039] The driver power supply 421 may include a filter 422 (eg, a low pass filter) and the driver 430 may output a filtered driver supply voltage ( VCC2 ) and an unfiltered (ie, digital) driver supply voltage (VCCD).

[0040] The driver 430 of the switching regulator 400 includes a driver wake-up circuit 500. When the enable transistor 412 is in the on state, the driver wake-up circuit 500 is coupled to the controller power supply 411 at the driver wake-up pin 432 (DRWK). The driver wake-up circuit 500 is also coupled to the driver power supply 421 (VCC) at the supply pin 435 via the filter 422.

[0041] Driver 430 includes an analog OR circuit configured to output the higher of two inputs. The analog OR is coupled to the controller power supply 411 at a first input and to the driver power supply 421 at a second input. The analog OR is configured to output the higher of the controller power supply 411 or the driver power supply 421 to a power node 513 of the driver 430.

[0042] In a possible specific implementation, the analog OR circuit includes a first diode 501 coupled between the driver wake-up pin 432 and the power node 513 and a second diode 502 coupled between the power supply pin 435 and the power node 513. The anode is oriented so that when the controller power supply 411 has a higher voltage than the driver power supply 421, the first diode 501 is turned on (i.e., conducting) and the second diode 502 is turned off (i.e., non-conducting, blocking). In addition, when the controller power supply 411 has a voltage lower than the driver power supply 421, the first diode 501 is turned off (i.e., blocking) and the second diode 502 is turned on (i.e., conducting).

[0043] Return to Figure 3 During the driver startup period 360 before the crossover time 330, the driver wake-up circuit 500 receives power from the controller power supply 411 through the first diode and draws negligible (e.g., zero) power (e.g., current) from the driver power supply 421 through the second diode 502. Alternatively, after the crossover time 330, the driver wake-up circuit 500 receives power from the driver power supply 421 through the second diode and draws negligible (e.g., zero) power (e.g., current) from the controller power supply 411 through the first diode 501. Therefore, the driver wake-up circuit 500 is powered to operate before the driver power supply 421 is ready (i.e., before the driver ready time 340).

[0044] Return to Figure 4, the driver wake-up circuit 500 also includes an output transistor 503. In a possible specific implementation, the output transistor 503 is an N-type MOSFET transistor. The output transistor 503 is coupled to the temperature monitoring pin 431 (TMON) of the driver 430 at the drain terminal (D), coupled to the ground 505 at the source terminal (S), and coupled to the power node 513 via a pull-up resistor 506 at the gate terminal (G). A second resistor (R2) can be coupled between the gate terminal and the second diode 502 to help set the voltage at the gate terminal. When the output transistor 503 is in the on state, the temperature monitoring pin 431 is shorted to the ground 505. When the output transistor is in the off state, the temperature monitoring pin 431 is decoupled from the driver wake-up circuit 500.

[0045] The driver wake-up circuit 500 also includes a bypass transistor 504. In a possible specific implementation, the bypass transistor 504 is an N-type MOSFET transistor. The bypass transistor 504 is coupled to the gate terminal (G) of the output transistor 503 at the drain terminal (D2) and is coupled to the ground 505 at the source terminal (S2). The bypass transistor 504 is controlled to be in an on state or an off state by a threshold circuit 510 coupled to the bypass transistor 504 at the gate terminal (G2). When the bypass transistor 504 is in the on state, the gate terminal (G) of the output transistor 503 is pulled down to the ground 505. When the bypass transistor 504 is in the off state, the gate terminal (G) of the output transistor 503 can be pulled up to the voltage of the power node 513 (e.g., V CON ).

[0046] The threshold circuit 510 is configured to receive the driver supply voltage (i.e., VCC) at the supply pin 435 and compare the driver supply voltage to a power-on reset (POR) threshold. In a possible implementation, the output of the threshold circuit 510 is a relatively low voltage when the driver supply voltage is less than the POR threshold, and the output of the threshold circuit 510 is a relatively high voltage when the driver supply voltage is greater than or equal to the POR threshold. In a possible implementation, the POR threshold can be set (e.g., factory set, user defined) to the driver power ready voltage 390. In this implementation, when the driver power supply 421 is ready, the bypass transistor 504 can be configured to be in an on state to pull down the gate terminal of the output transistor 503.

[0047] Driver 430 may also include temperature sensing circuit 434. Temperature sensing circuit 434 may include a temperature sensor and a temperature amplifier (T_amp) configured to convert the temperature of a phase of multi-phase switching regulator 100 into a voltage. When temperature sensing circuit 434 is enabled, a voltage may be transmitted to temperature monitoring pin 431.

[0048] The temperature sensing circuit 434 may be enabled by an internal enable signal (EN_INT). For example, the temperature sensing circuit 434 may be enabled when the driver 430 is in an operating mode. In a possible implementation, the temperature sensing circuit 434 is enabled by a high internal enable signal and disabled by a low internal enable signal.

[0049] The internal enable signal (EN_INT) may be generated by the internal enable circuit 433. The internal enable circuit 433 may include a logic circuit (e.g., an AND gate). In a possible implementation, the internal enable signal is high when both the driver wake-up signal (DRWK) and the communication bus enable signal (EN_DB) are high. The communication bus enable signal is an enable message sent over the communication bus 140 after the driver is ready and communication is established over the communication bus 140 (i.e., in the operating mode). Otherwise, the internal enable signal is low, and the temperature sensing circuit 434 is decoupled from the temperature monitoring pin 431.

[0050] It should be noted that the controller can still use the disclosed techniques to check the driver ready state even when the communication bus 140 is not present or is not used for this purpose. In these specific implementations, although the driver is not fully powered by its own power supply to determine when to send the PWM adjustment signal, the controller still checks the driver ready state based on the state of the TMON pin. For example, adjustment can begin immediately after the TMON pin indicates that the driver is ready. Alternatively, adjustment can begin after a waiting period that is set (e.g., factory set) or programmed (e.g., user defined) to allow operation of the driver (e.g., communication) to begin. None of these alternatives require the communication bus 140.

[0051] As previously described, when a driver wake-up signal (DRWK) is received, the driver may be configured in a startup mode. During the startup mode, the driver wake-up circuit 500 may be enabled to output the state of the driver power supply 421 to the temperature monitoring pin 431 of the driver. The driver wake-up circuit 500 may be enabled for operation based on the power received from the controller power supply or based on the power received from the driver power supply. As currently described, the selection of which power supply to use to enable the driver wake-up circuit 500 for operation is based on a comparison between the driver supply voltage and the controller supply voltage, but there may be alternative specific implementations. For example, a threshold value may be set and compared to determine when the driver power supply is at a voltage sufficient to control (e.g., bias) the transistors (e.g., output transistor 503, bypass transistor 504) of the driver wake-up circuit 500. The threshold value may or may not be equal to the controller supply voltage.

[0052] Return to Figure 3, during the driver startup period 360, the driver is in the not ready state while its voltage is below the POR threshold, which may be set equal to the driver supply ready voltage 390. The driver may be in the not ready state even when the voltage of the driver is greater than the controller supply voltage 301. For example, the driver may (i) be in the not ready state and (ii) have a driver supply voltage 302 that is less than the controller supply voltage 301 during a first period between the controller ready time 320 and the crossover time 330. In addition, the driver may (i) be in the not ready state and (ii) have a driver supply voltage 302 that is greater than the controller supply voltage 301 during a second period between the crossover time 330 and the driver ready time 340.

[0053] Figure 5A FIG. 2 shows a driver wake-up circuit in a driver not ready state according to a possible specific implementation of the present invention. In the state shown, the driver supply voltage (V DRV ) is less than the controller supply voltage. Therefore, the second diode 502 blocks the driver power supply 421 (i.e., is turned off), while the first diode 501 couples the controller power supply 411 (i.e., is turned on). In addition, the bypass transistor 504 is in the off state because the driver supply voltage (V DRV ) is less than the POR threshold. Therefore, the gate terminal of the output transistor 503 is pulled up along the first pull-up path 521 in the on state including the pull-up resistor 506, the first diode 501 and the enable transistor 412. The voltage at the gate terminal of the output transistor 503 is sufficient to configure the output transistor 503 to the on state. Therefore, the temperature sensing pin 415 of the controller is shorted to ground along the short-to-ground path 522.

[0054] The ready detection circuit 401 included in the switching regulator 400 is configured to compare the voltage at the temperature sensing pin 415 with the ready threshold 403. In a possible implementation, the ready detection circuit 401 includes a comparator 402 coupled to the temperature sensing pin 415 at a first input and coupled to a voltage source corresponding to the ready threshold 403 at a second input. When the temperature monitoring pin 431 is shorted to ground, as shown in FIG. Figure 5A As shown, the ready detection circuit 401 may be configured to output a not ready signal based on the voltage at the temperature sensing pin 415 being less than the ready threshold 403 .

[0055] Figure 5B1 shows a driver wake-up circuit in a driver ready state according to a possible implementation of the present invention. In the state shown, the driver supply voltage (VDRV) is greater than (or equal to) the controller supply voltage. Therefore, the first diode 501 blocks the controller power supply 411 (i.e., disconnected), while the second diode 502 couples the driver power supply 421 (i.e., connected), so that there is a second pull-up path 531 through the pull-up resistor 404. In addition, the bypass transistor 504 is in the on state because the driver supply voltage (V DRV ) is greater than (or equal to) the POR threshold. Therefore, the gate terminal of the output transistor 503 is shorted to ground along the bypass path 532, which configures the output transistor 503 to be in an off state. Therefore, the drain terminal of the output transistor 503 is an open drain, so that the temperature sensing pin 415 of the controller is open.

[0056] When the temperature monitoring pin 431 is open, the ready detection circuit 401 can be configured to pull up the temperature sensing pin 415 to a voltage (i.e., a high voltage) above the ready threshold 403 along the open pull-up path 533. Therefore, the comparator 402 is configured to output a ready signal. And the controller is triggered to configure the multi-phase switching regulator 100 to be in an operating mode. The temperature monitoring pin 431 remains decoupled from the temperature sensing circuit 434 until the controller establishes communication with the driver through the communication bus 140 and sends a communication bus enable signal.

[0057] Figure 5C A driver wake-up circuit in an operational state according to a possible specific implementation of the present invention is shown. In the state shown, the controller 410 has been triggered by the ready signal to configure the switching regulator 400 to be in an operational mode. In the operational mode, the enable transistor 412 remains in an on state, but is decoupled from the driver wake-up circuit 500 by the first diode 501 that remains in an off state. Therefore, in the operational mode, the driver wake-up circuit 500 draws very little current (e.g., leakage current) from the controller power supply 411. The output transistor 503 remains in an off state, so that the driver wake-up circuit 500 is decoupled from the temperature monitoring pin 431. In the operational mode, the temperature sensing circuit 434 is configured to generate a voltage (V corresponding to the sensed temperature) corresponding to the sensed temperature. TEMP ) is transmitted to the temperature monitoring pin 431. The controller 410 receives the voltage (V TEMP ), the temperature monitoring circuit 409 is coupled to the temperature sensing pin 415 of the switching regulator 400 through the switch 414.

[0058] Figure 66 is a flow chart of a method for sensing a ready state of a driver in a switching regulator according to a possible implementation of the present disclosure. The method 600 includes starting 610 a controller power supply (VCC1) for powering a controller of the switching regulator. The method 600 also includes coupling 620 the controller power supply to the driver of the switching regulator. For example, when the controller is ready for operation (e.g., has increased and stabilized at a controller power ready voltage), the controller power supply may be coupled to the enable bus 150 through an enable transistor 412 of the controller. The method 600 also includes enabling 630 a driver power supply (VCC2) for powering the driver. For example, when a controller supply voltage from the enable bus is received at a driver wake-up pin of the driver, the driver power supply may be enabled (e.g., activated, turned on, etc.).

[0059] The method 600 also includes comparing a driver supply voltage of the driver power supply to a controller supply voltage of the controller power supply 640. Based on the comparison, the method 600 also includes using the controller power supply to power a driver wake-up circuit of the driver 650 (and blocking the driver power supply) when the driver supply voltage is less than the controller supply voltage. Alternatively, the method 600 includes using the driver power supply to power a driver wake-up circuit 660 (and blocking the controller power supply) when the driver supply voltage is greater than the controller supply voltage.

[0060] When the driver supply voltage is less than the POR threshold, method 600 includes configuring 680 the driver wake-up circuit to generate a short circuit condition at the temperature monitoring pin of the driver. Figure 5A As shown, configuring the driver wake-up circuit may include configuring the output transistor 503 ( Q1 ) of the driver wake-up circuit 500 to be in an on state and configuring the bypass transistor 504 ( Q2 ) of the driver wake-up circuit 500 to be in an off state.

[0061] When the driver supply voltage is greater than or equal to the POR threshold, method 600 includes configuring 680 the driver wake-up circuit to generate an open circuit state at the driver's temperature monitoring pin. Figure 5B As shown, configuring the driver wake-up circuit may include configuring the output transistor 503 ( Q1 ) of the driver wake-up circuit 500 to be in an off state and configuring the bypass transistor 504 ( Q2 ) of the driver wake-up circuit 500 to be in an on state.

[0062] The method 600 also includes sensing a ready state of the driver based on the state of the temperature monitoring pin (ie, short circuit or open circuit).

[0063] Figure 7 It shows that Figure 6Flowchart of a method for sensing a temperature monitoring pin for use in conjunction with a method of . Method 700 includes enabling a controller to sense the state of a temperature monitoring pin. This may include connecting 710 an input of a ready detection circuit to the temperature monitoring pin (e.g., via a temperature bus). Method 700 may also include receiving an open circuit state or a short circuit state at an input to the ready detection circuit (i.e., at a temperature sensing pin of the controller). When an open circuit state exists, method 700 includes pulling up the temperature monitoring pin to a voltage (V) greater than a ready threshold (i.e., V = high). When a short circuit state exists, the temperature monitoring pin is shorted to a voltage less than the ready threshold (i.e., V = low). Method 700 includes pulling the voltage at the temperature monitoring pin (V TMON ) is compared to a ready threshold. When the voltage is greater than or equal to the ready threshold, then the driver is in a ready state 780, otherwise the driver is in a not ready state 770. After the driver is in the ready state 780, the method 700 may include connecting 790 a temperature monitoring circuit of the driver to the temperature monitoring pin to resume temperature reporting of the driver.

[0064] In the specification and / or drawings, typical embodiments have been disclosed. The present disclosure is not limited to such exemplary embodiments. The use of the term "and / or" includes any and all combinations of one or more associated listed items. The drawings are schematic representations and are therefore not necessarily drawn to scale. Unless otherwise specified, specific terms have been used in a general and descriptive sense, not for limiting purposes.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those of ordinary skill in the art. Methods and materials similar or equivalent to those described herein may be used in the practice or testing of the present disclosure. As used in this specification and in the appended claims, the singular forms "one", "a", "the" include multiple referents unless the context clearly specifies otherwise. The term "include" and its variants as used herein are used synonymously with the term "include" and its variants, and are open-ended, non-restrictive terms. The term "optional" or "optionally" used herein refers to the features, events or situations described subsequently that may or may not occur, and the description includes instances where the features, events or situations occur and instances where they do not occur. The range can be expressed herein as from "about" a specific value, and / or to "about" another specific value. When such a range is expressed, one aspect includes from a specific value and / or to another specific value. Similarly, when a value is expressed as an approximation by using the antecedent "about", it should be understood that the specific value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both relative to the other endpoint, and independently of the other endpoint.

[0066] Some implementations may be implemented using various semiconductor processing and / or packaging technologies. Some implementations may be implemented using various types of semiconductor processing technologies associated with semiconductor substrates, including but not limited to, for example, silicon (Si), gallium arsenide (GaAs), gallium nitride (GaN), silicon carbide (SiC), etc.

[0067] Although certain features of the described implementations have been described as described herein, those skilled in the art will now appreciate that many modifications, alternatives, variations, and equivalents are contemplated. Therefore, it should be understood that the appended claims are intended to cover all such modifications and variations that fall within the scope of the implementations. It should be understood that these modifications and variations are presented only by way of example and not limitation, and that various changes in form and detail may be made. In addition to mutually exclusive combinations, any portion of the apparatus and / or method described herein may be combined in any combination. The implementations described herein may include various combinations and / or sub-combinations of the functions, components, and / or features of the different implementations described.

[0068] It will be understood that in the foregoing description, when an element is referred to as being on another element, connected to another element, electrically connected to another element, coupled to another element, or electrically coupled to another element, the element may be directly on another element, connected or coupled to another element, or one or more intermediate elements may be present. On the contrary, when an element is referred to as being directly on another element, directly connected to another element, or directly coupled to another element, there is no intermediate element. Although the term directly on, directly connected to, or directly coupled to may not be used throughout the specific embodiments, the element shown as being directly on an element, directly connected, or directly coupled can be mentioned in this manner. The claims of the present application, if present, may be revised to narrate the example relationships described in the specification or shown in the accompanying drawings.

[0069] As used in this specification, singular forms may include plural forms unless the context clearly indicates a particular case. Spatially relative terms (e.g., above, above, above, below, below, below, below, etc.) are intended to cover different orientations of the device in use or operation, in addition to the orientations shown in the drawings. In some specific implementations, the relative terms above and below may include vertically above and vertically below, respectively. In some specific implementations, the term adjacent can include lateral adjacent or horizontal adjacent.

Claims

1. A switching regulator, comprising: a driver coupled to a driver power supply; a controller coupled to a controller power supply and configured to couple the controller power supply to the driver during a startup period; and A driver wake-up circuit is included in the driver and is configured to receive power from the controller power supply during the startup period to control a temperature monitoring pin of the driver according to a driver supply voltage of the driver power supply.

2. The switching regulator of claim 1 , wherein the controller is configured to: coupling the controller power supply to the driver during the startup period when the controller power supply reaches a controller power ready voltage corresponding to the controller being ready for operation; and The temperature monitor pin of the driver is monitored during the startup period to determine when the driver power supply reaches a driver supply ready voltage corresponding to the driver being ready for operation.

3. The switching regulator according to claim 1 , wherein the driver wake-up circuit is configured to: receiving power from the controller power supply when the driver supply voltage is less than a controller supply voltage of the controller power supply; and When the driver supply voltage is greater than the controller supply voltage of the controller power supply, power from the controller power supply is blocked.

4. The switching regulator of claim 1 , wherein the driver wake-up circuit is configured to control an output transistor (Q1) coupled to the temperature monitoring pin of the driver to: The driver is in a disconnected state when the driver supply voltage is greater than or equal to a power-on reset threshold; and The driver is in an on state when the driver supply voltage is less than the power-on reset threshold.

5. The switching regulator of claim 4, wherein the temperature monitoring pin of the driver is coupled to an input of a ready detection circuit of the controller.

6. The switching regulator of claim 5 , wherein the ready detection circuit is configured to: When the input is open drain, the input is pulled up to a high voltage that is above the ready threshold.

7. The switching regulator of claim 5, wherein the ready detection circuit is configured to: A ready signal or a not ready signal is output based on a comparison between the input and a ready threshold.

8. The switching regulator of claim 7, wherein the controller is further configured to: determining that the drive is ready based on the ready signal; and An enable signal is transmitted to trigger the driver to enable a temperature sensing circuit to transmit to the temperature monitoring pin of the driver.

9. The switching regulator of claim 1, wherein the driver wake-up circuit is coupled to the controller power supply via a driver wake-up pin (DRWK) and to the driver power supply (VCC) via a power pin.

10. The switching regulator of claim 9, wherein the driver wake-up circuit comprises: a first diode coupled between the driver wake-up pin and a power node of the driver wake-up circuit; a second diode coupled between the power pin and the power node of the driver wake-up circuit; an output transistor coupled to the temperature monitoring pin at a first drain terminal (D), coupled to ground at a first source terminal (S), and coupled to the power node via a pull-up resistor at a first gate terminal (G); and A bypass transistor is coupled at a second drain terminal (D2) to the first gate terminal (G) and the power node via the pull-up resistor, coupled at a second source terminal (S2) to the ground, and coupled at a second gate (G2) terminal to a threshold circuit, the threshold circuit being configured to output a low signal when the driver supply voltage is below a power-on reset threshold and to output a high signal when the driver supply voltage is above the power-on reset threshold.

11. The switching regulator of claim 1 , wherein the driver is one of a plurality of drivers, the plurality of drivers: coupled to the controller power supply via an enable bus at a corresponding driver wake-up pin, wherein the enable bus is coupled to the controller power supply via an enable transistor of the controller; and A readiness detection circuit is coupled to the controller via a temperature bus at a corresponding temperature monitoring pin, wherein each temperature monitoring pin is configured to be powered by the controller power supply to communicate a status of each driver power supply to the temperature bus during the startup period.

12. The switching regulator of claim 1 , wherein the driver further comprises: a high-side transistor and a low-side transistor coupled in a series connection between the driver power supply and ground; a switch node pin coupled between the high-side transistor and the low-side transistor; and A gate driver circuit is configured to switch the high-side transistor and the low-side transistor according to a pulse width modulation (PWM) signal received at a pulse width modulation (PWM) pin, wherein the gate driver circuit, the high-side transistor and the low-side transistor are integrated together in an integrated circuit.

13. A method for sensing a ready state of a driver of a switching regulator, the method comprising: activating a controller power supply for a controller of the switching regulator; coupling the controller power supply to the driver of the switching regulator; enabling a driver power supply for the driver of the switching regulator; comparing a driver supply voltage of the driver power supply with a controller supply voltage of the controller power supply; powering a driver wake-up circuit of the driver using the greater of the driver supply voltage and the controller supply voltage; comparing the driver supply voltage to a power-on reset threshold using the driver wake-up circuit; When the driver supply voltage is less than a power-on reset threshold, configuring the driver wake-up circuit to generate a short circuit state at a temperature monitoring pin of the driver; configuring the driver wake-up circuit to generate an open circuit state at the temperature monitoring pin of the driver when the driver supply voltage is greater than the power-on reset threshold; as well as The ready state of the driver is sensed based on the short circuit state or the open circuit state of the temperature monitoring pin.

14. The method of claim 13, wherein the driver power supply is enabled when the controller power supply reaches a controller power-ready voltage.

15. The method of claim 13, wherein sensing the ready state of the drive comprises: When the temperature monitoring pin is in the short circuit state, it is determined that the voltage of the temperature monitoring pin is less than a ready threshold.

16. The method of claim 13, wherein sensing the ready state of the drive comprises: When the temperature monitoring pin is in the open circuit state, it is determined that the voltage of the temperature monitoring pin is greater than a ready threshold.

17. The method of claim 16, wherein when the temperature monitoring pin is in the open circuit state, determining that the voltage of the temperature monitoring pin is greater than the ready threshold comprises: When the temperature sensing pin is coupled to the temperature monitoring pin in the open circuit state, the temperature sensing pin is pulled up to a high voltage level above the ready threshold.

18. The method according to claim 16, further comprising: decoupling a temperature sensing circuit from the temperature monitoring pin when the driver power supply is enabled; as well as After the driver is ready, the temperature sensing circuit is recoupled to the temperature monitoring pin.

19. A multi-phase switching regulator, comprising: a controller configured to receive power from a first power supply at a first supply pin and to couple the power from the first power supply to a driver enable pin; a first driver coupled to the driver-on pin via a first driver wake-up pin and to a second power supply via a second power supply pin, the first driver being configured to: When the second power supply voltage is less than the first power supply voltage, receiving power from the first power supply and blocking power from the second power supply; and a second driver coupled to the driver on pin via a second driver wake-up pin and to a third power supply at a third power supply pin, the second driver being configured to: When the third power supply voltage is lower than the first power supply voltage, power from the first power supply is received and power from the third power supply is blocked.

20. The multiphase switching regulator of claim 19, wherein: The first driver is further configured to block power from the first power supply and receive power from the second power supply when the second power supply voltage is greater than the first power supply voltage; and The second driver is further configured to block power from the first power supply and receive power from the third power supply when the third power supply voltage is greater than the first power supply voltage.

21. The multiphase switching regulator of claim 19, wherein: The first driver is further configured to control a first state of a first temperature monitoring pin based on a comparison of the second supply voltage and a first threshold; and The second driver is further configured to control a second state of a second temperature monitoring pin based on a comparison of the third supply voltage with a second threshold.

22. The multi-phase switching regulator of claim 21 , wherein the controller comprises a ready detection circuit coupled to the first temperature monitoring pin and the second temperature monitoring pin, the ready detection circuit being configured to: A ready state of the first driver is sensed based on the first state of the first temperature monitoring pin, and the ready state of the second driver is sensed based on the second state of the second temperature monitoring pin.

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