Control method and control device

Abstract

This invention discloses a control method and a control device, wherein the control device includes an energy transfer device that operates one or more input switches on the input side of an isolation device to transfer energy through the isolation device to the output side of the isolation device for activating the switches. The device includes a voltage conversion device that converts energy from an input voltage on the input side to an output voltage to control the switches when energy transfer is valid. The device includes a passive shutdown device that passively deactivates the switches when energy transfer is invalid. When energy transfer is valid, the passive shutdown device is prevented from deactivating the switches.

Description

Technical Field

[0001] This disclosure relates to the field of operating switches through an isolation barrier. Background Technology

[0002] Various types of devices can utilize switches, such as solid-state switches. Switches can be controlled via the device's power domain. The power domain can be isolated relative to the area within the device where the switch is located. Isolation can also be achieved using optical isolation barriers. These barriers are positioned within the device between a first side comprising the power domain and a second side comprising the switch. To control the switch across the optical isolation barrier, information and / or energy must be transmitted across it. Unfortunately, the manufacturing costs associated with producing optically isolated switches are prohibitively high.

[0003] Many existing solutions, such as those using current isolation as an alternative to optical isolation, are based on capacitive or transformer coupling, both of which require integration capabilities. These solutions have various drawbacks. One such drawback is the need for additional dedicated power supply pins on one or more sides of the isolation barrier. Another drawback is the inability to integrate the isolation barrier and solid-state switch into the same package. Yet another drawback is the lack of pin-to-pin compatibility with other isolation devices used to drive solid-state switches, such as optocouplers or solid-state relays. Furthermore, existing isolation solutions are not always able to generate a voltage on the output side of the isolation barrier (e.g., the second side where the switch is located) higher than on the input side (e.g., the first side where the power domain is located). This severely restricts and limits the types of switches that can be used, as such switches would have to have a threshold voltage compatible with the input voltage range, which may be too low relative to the voltage used to operate the switch. A drawback of capacitive isolation is common-mode transient immunity between the two sides of the isolation barrier, which causes the potentials on both sides of the isolation barrier to move rapidly in opposite directions. Although some products can combine these isolation solutions and / or one or more of their characteristics, there is currently no product that can simultaneously solve all of the aforementioned drawbacks. Summary of the Invention

[0004] This summary is provided to introduce a series of concepts in a simplified form, which will be further described in the detailed description below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

[0005] In an embodiment of the technology proposed herein, a method is provided. The method includes: operating one or more input switches on the input side of an isolation device according to a frequency and duty cycle to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles for activating the switches. A voltage conversion device converts the energy from the input voltage on the input side into an output voltage to control the switches. When energy transfer is active, a passive turn-off device is disabled to deactivate the switches. When energy transfer is inactive, the passive turn-off device passively deactivates the switches.

[0006] In embodiments of the technology presented herein, an apparatus is provided. The apparatus includes means for operating one or more input switches on the input side of an isolation device according to a frequency and duty cycle to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles for activating the switches. The apparatus includes means for converting energy from an input voltage on the input side into an output voltage to control the switches. The apparatus includes means for passively deactivating the switches when energy transfer is invalid. The apparatus includes means for disabling deactivation of the switches when energy transfer is valid.

[0007] In an embodiment of the technology proposed herein, an apparatus is provided. The apparatus includes an energy transfer device configured to operate one or more input switches on the input side of an isolator according to a frequency and duty cycle to transfer energy through the isolator to the output side of the isolator during a series of switching cycles for activating the switches. The apparatus includes a voltage conversion device configured to convert energy from an input voltage on the input side to an output voltage to control the switches when energy transfer is active. The apparatus includes a passive shutdown device configured to passively deactivate the switches when energy transfer is inactive. The apparatus includes a negative charge pump configured to prevent the passive shutdown device from deactivating the switches when energy transfer is active.

[0008] In an embodiment of the technology presented herein, an apparatus is provided. The apparatus includes an energy transfer device configured to operate one or more input switches on the input side of an isolation device to transfer energy through the isolation device to the output side of the isolation device for activating the switches. The apparatus includes a voltage conversion device configured to convert energy from an input voltage on the input side to an output voltage to control the switches when energy transfer is active. The apparatus includes a passive shutdown device configured to passively deactivate the switches when energy transfer is inactive, wherein the passive shutdown device is prevented from deactivating the switches when energy transfer is active.

[0009] To achieve the foregoing and related objectives, the following description and accompanying drawings illustrate some illustrative aspects and implementations. These illustrative aspects and implementations indicate only some of the various ways in which one or more aspects can be adopted. Other aspects, advantages, and novel features of this disclosure will become apparent from the following detailed description when considered in conjunction with the accompanying drawings. Attached Figure Description

[0010] Figure 1 This is an illustration of an example method for operating a switch through an isolation device according to the technology proposed in this paper.

[0011] Figure 2 This is a component block diagram illustrating a device for operating a switch through an isolation device according to the technology proposed herein.

[0012] Figure 3 This is a block diagram illustrating the composition of a device according to the technology proposed herein, comprising a flyback converter, a transformer for operating the switch through an isolation device, a switch controlled by the device, a negative charge pump, and a depletion-type NMOS as a passive turn-off device.

[0013] Figure 4A This is a block diagram illustrating the composition of a device according to the technology proposed herein, comprising a voltage multiplier, a transformer for operating a switch through an isolation device, a switch controlled by the device, a negative charge pump, and a depletion-type NMOS as a passive turn-off device.

[0014] Figure 4B This is a block diagram illustrating the composition of a device according to the technology proposed herein, comprising a voltage multiplier, a capacitive coupling device for operating a switch through an isolation device, a switch controlled by the device, a negative charge pump, and a depletion-type NMOS as a passive turn-off device. Detailed Implementation

[0015] The claimed subject matter will now be described with reference to the accompanying drawings, wherein similar reference numerals are used to denote similar elements. In the following description, numerous specific details are set forth for illustrative purposes to provide a thorough understanding of the claimed subject matter. However, it will be apparent that the claimed subject matter can be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form to facilitate the description of the claimed subject matter.

[0016] In the field of electronics, a device includes a switch to be controlled via a region of the device isolated from the switch (such as the power domain region of the device). The ability to operate the switch is enhanced by using electrical isolation (e.g., by utilizing capacitive coupling devices, transformers such as cored or coreless transformers or any other type of transformer, or other electrical isolation barriers). Electrical isolation barriers can be used in a manner that does not introduce topological differences or losses into the device, and thus the device can be easily interchanged with other existing devices without introducing significant differences in, for example, device size, packaging, or leads. For example, pin-to-pin compatibility is provided because additional pins are not required to otherwise provide dedicated power on either side of the electrical isolation barrier.

[0017] The techniques and apparatus provided herein enable the transfer of a sufficient amount of energy from a first side of the device (e.g., the side where the power domain region is located) across an electrical isolation barrier to a second side of the device where the switch is located. The transfer of energy over a series of switching cycles allows for the correct and reliable switching (e.g., a solid-state switch) at a sufficiently high speed without requiring additional energy from the second side. Furthermore, power to the switch is safely switched off at a sufficient speed without the need to transfer energy across the electrical isolation barrier or require external components.

[0018] In this implementation, an integrated energy transfer process is provided across an isolation barrier, such as an electrical isolation barrier. Energy is transferred from the input side of the isolation barrier to its output side to ensure the correct, complete, and safe activation of a switch (e.g., a solid-state switch) located on the output side. Energy is transferred during a series of switching cycles, during which the energy transfer is either active or inactive. The switch is activated at a sufficient speed without requiring additional energy from the output side. This can be achieved by implementing on-off keying technology, which is used to store and release electromagnetic energy across the isolation barrier for transfer to the output side in a manner compatible with the energy loss allowed by the isolation barrier. On-off keying includes a high-frequency pulse drive on the input side, where a switching mode is used to apply a drive between the input power supply and input ground to the input terminals of the isolation barrier. To interrupt the energy transfer process, the switching mode is stopped so that no current flows within the isolation barrier. Various types of energy transfer devices can be used to perform the integrated energy transfer process.

[0019] In this implementation, a sufficiently high output voltage can be generated on the output side to ensure the use of various types of switches, such as MOSFETs, IGBTs, or other types of switches. The output voltage can be relatively higher than the input voltage used on the input side. This can be achieved by utilizing various boost rectifier topologies that can be coupled to the output side, such as flyback converters, voltage multipliers (e.g., Cockroft-Walton voltage multipliers), or other types of voltage conversion devices. The voltage conversion device can be used to achieve an output voltage capable of driving the gate of the switch, which can be a voltage higher than the voltage used on the input side. The activation of the power conversion process of the voltage conversion device is activated and controlled according to the on / off keying on the primary side. In this implementation, auxiliary functions (e.g., current sensing or temperature sensing for the switch) can be powered on the output side by the output voltage provided by the voltage conversion device.

[0020] In implementation, a reliable passive turn-off path is provided for the gate of the switch. This can be achieved by utilizing various integration technology options, such as depletion-mode MOSFETs (e.g., n-channel depletion-mode MOSFETs or p-channel depletion-mode MOSFETs) or other types of passive turn-off devices that have a conductive channel even when they cannot be actively driven (e.g., when no active power is provided). The passive turn-off device is capable of reliably and passively turning off the switch without performing energy transfer from the input side to the output side.

[0021] In this implementation, the passive shutdown device can be quickly and reliably deactivated as soon as the energy transfer process begins. No additional energy from the input or output side is required for activation and deactivation of the passive shutdown device. Deactivation can be achieved through an on / off keying process that generates a negative voltage on the output side by means of a negative charge pump coupled to an isolation barrier (e.g., coupled to the secondary winding of a transformer used as an isolation barrier). In this implementation, by means of the negative charge pump, as soon as the on / off keying process begins, the gate of the passive shutdown device, such as a depletion-type MOSFET (e.g., a depletion-type n-channel MOSFET), can be actively driven below its source to prevent the depletion-type MOSFET from turning on. In this way, the depletion-type MOSFET is deactivated. This causes the rising voltage driving the switch to turn on the switch. Once the on / off keying process stops, the load of the negative charge pump should release the negative voltage at the output and allow the depletion-type MOSFET to turn on again. Specifically, a passive discharge element (e.g., a resistor connecting the source and gate of a depletion-type MOSFET) will bring the source and gate of the depletion-type MOSFET to the same voltage, thereby activating the depletion-type MOSFET. Once energy transfer stops, the passive discharge element will reduce the voltage previously generated by the negative charge pump to zero with an appropriate time constant. In an implementation, in contrast to a depletion-type n-channel MOSFET, a charge pump can be used to generate a positive voltage to control a depletion-type p-channel MOSFET.

[0022] In this way, electrical isolation is provided to the device in a manner that allows for reliable, safe, and fast control of switches (e.g., solid-state switches) without introducing topological differences or losses.

[0023] Figure 1 The exemplary method 100 illustrates an implementation of a control switch across an isolation barrier and combines it with Figures 2 to 4B This implementation will be described further. For example, Figure 2 The device 200 includes an isolation device 208 that isolates the input side 202 of the device 200 from the output side 216 of the device 200. The isolation device 208 may include an electrical isolation device that provides electrical isolation between the input side 202 and the output side 216 of the device 200. In some embodiments, the isolation device 208 includes a transformer, such as a coreless transformer or a cored transformer (e.g., Figure 3 Transformer 310 and Figure 4A Transformer 404 in the embodiment). In this embodiment, the isolation device 208 includes a capacitive coupling device (e.g., Figure 4B (Capacitive coupling device 456 in the middle). Isolation device 208 provides current isolation between input side 202 and output side 216.

[0024] Input side 202 includes input source 204. Input source 204 may be associated with an input power supply domain that provides an input voltage to input side 202. Input side 202 may include one or more input switches 218 (e.g., Figure 3 The single input switch SW in IN 304 or Figure 4A and Figure 4B The first input switch SW1A 418, the second input switch SW1B 422, the third input switch SW2A 420, and the fourth input switch SW2B 424 are included in the device 200. The input side 202 includes an energy transfer device 206 configured to operate one or more input switches 218 to perform multiple switching cycles to transfer energy through the isolation device 208 to the output side 216 for controlling the switch 212 located at the output side 216 of the device 200. The multiple switching cycles correspond to a series of switching cycles in which energy transfer is active or inactive. The energy transfer device 206 can operate one or more switches 218 according to a frequency (e.g., switching frequency) and duty cycle to transfer energy through the isolation device 208 during a switching cycle to activate the switch 212. In this embodiment, the energy transfer device 206 utilizes on / off keying technology to perform multiple switching cycles to transfer energy through the isolation device 208 to operate the switch 212.

[0025] Accordingly, at 102, one or more input switches 218 are operated according to the frequency and duty cycle to transfer energy through the isolation device 208 during a series of switching cycles to activate switch 212. In the embodiment, on / off keying is applied by operating one or more input switches 218 according to a determined frequency and duty cycle. The frequency can be set to a sufficiently high value to limit the current flowing through the primary winding of the isolation device 208 (e.g., a transformer) during the switching cycle. Depending on whether a flyback converter (e.g., Figure 3 ) or a voltage multiplier (e.g., Figure 4A and Figure 4B The voltage conversion device 210, used at the output side 216, can utilize different duty cycles. For example, for a voltage multiplier, the duty cycle can be set to 50%, where the energy transfer device 206 drives the energy in a push-pull manner. In this example, the switching cycle includes a first phase where the input current flows from the top terminal to the bottom terminal of the isolation device 208. The switching cycle includes a second phase where the input current flows from the bottom terminal to the top terminal. For a flyback converter, the duty cycle can be set based on the switching frequency so that the inductance across the isolation device 208 does not reach saturation or cause reliability issues.

[0026] If one or more input switches 218 are kept off via energy transfer device 206, no energy transfer occurs. If one or more switches 218 are turned on via energy transfer device 206, energy is transferred through isolation device 208 to output side 216 to turn on switch 212. In this way, energy transfer is performed as a series of switching cycles that are active or inactive.

[0027] Device 200 includes a voltage conversion device 210 located at the output side 216 of device 200. Voltage conversion device 210 may include a flyback converter (e.g., Figure 3 ), voltage multiplier (e.g., Figure 4A and Figure 4B For example, a Cocroft-Walton voltage multiplier, or other voltage conversion devices. Voltage conversion device 210 can be configured to convert energy transferred via energy transfer device 206 from an input voltage associated with input source 204 into an output voltage capable of controlling (e.g., turning on) switch 212. In embodiments, voltage conversion device 210 can convert the input voltage into a relatively high voltage as an output voltage capable of turning on switch 212 (e.g., turning on the gate of a solid-state switch). In this way, various types of switches 212 can be used that would otherwise not be operable with / compatible with the relatively low input voltage associated with input source 204. Voltage conversion device 210 outputs an output voltage when energy transfer via energy transfer device 206 is active. Therefore, at 104, when energy transfer is active, energy is converted from the input voltage on input side 202 into an output voltage to control switch 212.

[0028] Device 200 includes a passive shutdown device 214 (e.g., on the output side 216 of device 200) Figure 3 The passive shutdown device 318 and Figure 4A and Figure 4BPassive shutdown device 214 (428 in the embodiment). In this embodiment, passive shutdown device 214 includes a depletion-type MOSFET (e.g., a depletion-type n-channel MOSFET or a depletion-type p-channel MOSFET). When the power transfer device 206 is not performing power transfer and the switch 212 is otherwise activated, the passive shutdown device 214 passively (e.g., when no power needs to be supplied to the passive shutdown device 214) activates the switch 212 to turn it off. For example, when there is no power transfer, the capacitor on the output side 216 discharges, and the source and gate of the passive shutdown device 214 are at the same / similar potential, thus establishing a conductive channel between the source and drain of the passive shutdown device 214. The conductive channel acts as a resistor whose size is determined according to the size of the passive shutdown device 214, and applies a turn-off strength (e.g., by short-circuiting the gate and source of the switch 212) between the gate and source of the switch 212 to turn off the switch 212. In this way, when no energy transfer is being performed, the passive shut-off device 214 passively activates the switch 212 without using electricity for active driving.

[0029] When energy transfer is effective, the passive shutdown device 214 can be prevented from passively activating the switch 212. In an embodiment, a charge pump 220 (e.g., a positive charge pump for a depletion-type p-channel MOSFET) or a negative charge pump for a depletion-type n-channel MOSFET (e.g., ...) can be used. Figure 3 The negative charge pump 324 is used to prevent the passive shutdown device 214 from passively deactivating the switch 212 when energy transfer is active. For a depletion-type n-channel MOSFET, when energy transfer is active, the negative charge pump is used to actively drive down the gate of the depletion-type n-channel MOSFET with a negative voltage to prevent the depletion-type n-channel MOSFET from passively deactivating the switch 212. In this way, at 106, when energy transfer is active, the passive shutdown device 214 is prevented from passively deactivating the switch 212. When energy transfer is inactive, the load at the output of the negative charge pump discharges a negative voltage so that the depletion-type n-channel MOSFET can passively deactivate the switch 212. When there is no switching activity, the negative charge pump is inactive. In this way, at 108, when energy transfer is inactive, the passive shutdown device 214 can passively activate the switch 212.

[0030] Figure 3An embodiment of a device 300 for operating a switch 320 through an isolation barrier is shown. Device 300 includes a transformer 310 that operates as an isolation barrier to isolate the input side 312 of device 300 from the output side 314 of device 300, for example, through electrical isolation. Switch 320 is located on the output side 314 of device 300. Input source 302 and input switch 304 are located on the input side 312 of device 300. Switch 320, a passive turn-off device 318 (e.g., a depletion-type p-channel MOSFET), a voltage conversion device (e.g., a flyback converter utilizing diode D1 316, which is forward-biased or reverse-biased based on whether energy transfer occurs), and a negative charge pump 324 are located on the output side 314 of device 300. Negative charge pump 324 may include a resistor R1 and an equivalent capacitance C. G1 And / or diode D2.

[0031] On the input side 312, on / off keying is performed to operate the input switch 304 to perform a series of switching cycles, transferring energy (e.g., energy generated by the input source 302) from the input side 312 to the output side 314 to operate the switch 320. In this embodiment, the input switch 304 is turned on at the beginning of the switching cycle to drive the lower terminal of the primary side 306 of the transformer 310. This generates a magnetizing current Im 326 flowing into the equivalent magnetizing inductance Lm of the transformer 310. As long as the input switch 304 is turned on, the magnetizing current Im 326 of the transformer 310 will continue to increase. The duty cycle for switching the input switch 304 on and off is set based on the switching frequency so that the magnetizing current Im 326 does not reach transformer saturation or cause transformer reliability issues for the transformer 310. While input switch 304 is turned on and magnetizing current Im 326 flows into the primary winding of transformer 310, the secondary winding of transformer 310 (which provides a reverse voltage relative to the voltage applied to the primary winding) holds diode D1 316 in reverse bias so that no current flows through the gate of switch 320. After this duty cycle phase, input switch 304 is turned off and the lower terminal of the primary side 306 of transformer 310 is left floating.

[0032] Magnetic energy stored in transformer 310 (e.g., corresponding to the peak magnetizing current Im reached in the stage before input switch 304 is turned on) is output through the secondary side 308 of transformer 310, thereby causing a demagnetizing current. Therefore, the stored magnetic energy is released through a reduced Idm (e.g., the magnetic energy stored in transformer 310) appearing on the secondary side 308 of transformer 310, and the voltage on the secondary side 308 is reflected in the primary voltage on the primary side. Diode D1 316 is forward biased, and the gate of switch 320 is connected to the equivalent capacitance C. G2322 (e.g., represented as the gate capacitance of switch 320) is charged until Idm disappears or the next switching cycle begins. Each charge packet from the primary side 306 to the secondary side 308 of transformer 310 will cause the equivalent capacitance C to... G2 The voltage across 322 increases until it reaches C. G2 The voltage thresholds at both ends will prevent the diode D1316 from being further forward biased.

[0033] In this implementation, the winding ratio of transformer 310 can be changed for a higher output voltage. In this way, at the start of energy transfer, there is energy flowing through diode D1 316 and a sinking current flowing through diode D2, both of which pull up the equivalent capacitance C. G2 The voltage (e.g., output voltage) of the top plate of the 322 and the equivalent pull-down capacitance C G1 The voltage on the base plate (e.g., the gate capacitance at a depletion-type n-channel MOSFET) causes the equivalent capacitance C to be such that... G2 As the voltage across diode 322 increases with energy transfer through diode D1 316, passive shutdown device 318 is prevented from deactivating switch 320 (e.g., passive shutdown device 318 is disabled during energy transfer). Equivalent capacitance C G1 This represents the gate capacitance of the passive shutdown device 318. When switching on the primary side is active (e.g., on / off keying is active), resistor R1 is used as the equivalent gate capacitance C of the passive shutdown device 318 so as not to adversely affect the negative charge pump 324 from fully pumping the passive shutdown device 318. G1 A specific amount of load (e.g., a load below a threshold load) is applied to the negative charge pump 324, causing the gate voltage of the passive shutdown device 318 to be more negative than its source voltage. In other words, when a load is applied to the negative charge pump 324, resistor R1 does not prevent the negative charge pump 324 from disabling the passive shutdown device 318 because resistor R1 can be configured as a load below the load threshold to prevent overloading of the negative charge pump 324. Once switching on the primary side stops (e.g., the on / off key is disabled), the negative charge pump 324 can no longer pump a gate voltage more negative than the source voltage of the passive shutdown device 318. Therefore, resistor R1 can begin to make the equivalent capacitance C... G1 Discharge, thereby causing the equivalent capacitance C G1 The gate and source reach the same voltage again.

[0034] Resistor R1 corresponds to the design parameters because it should have at least a threshold resistance such that the negative charge pump 324 is not overloaded when switching on the primary side is active (e.g., on-key active), preventing and / or preventing the adverse consequences of the gate of the passive shutdown device 318 being pulled down relative to the source due to overloading of the negative charge pump 324 in other ways. Simultaneously, when switching on the primary side is stopped (e.g., on-key inactive), resistor R1 should be low enough to reduce the equivalent capacitance C within a reasonable time. G1 Discharge. The equivalent capacitance C, determined by resistor R1. G1 The discharge time will determine the turn-off speed of switch 320. Therefore, the determination of the size of resistor R1 depends on the trade-off efficiency between the deactivation efficiency of passive turn-off device 318 and the turn-off speed of switch 320.

[0035] To avoid transformer 310 saturation, the flyback converter operates in discontinuous conduction mode (DCM), causing Idm (e.g., magnetic energy stored in transformer 310) to discharge to zero after each switching cycle without energy accumulation between switching cycles. Therefore, the duty cycle of input switch 304 is set such that Im does not become too high during the time input switch 304 is on, and Idm is fully discharged when input switch 304 is off. Since all current flowing into the forward-biased diode D1 316 disappears when diode D1 316 is reverse-biased, this avoids reverse recovery losses in diode D1 316.

[0036] A flyback converter is used as a voltage conversion device. The flyback converter converts energy from the input voltage to the output voltage to control switch 320. In this way, the equivalent capacitance C... G2 The voltage across 322 (e.g., the output voltage) can be relatively larger than the input voltage of the input source 302.

[0037] The passive turn-off device 318 (e.g., a depletion-type n-channel MOSFET) is connected to the equivalent capacitance C. G2 322 is used in parallel to ensure the passive turn-off of switch 320. In the steady state where there is no effective energy transfer and input switch 304 is off, the capacitor (e.g., equivalent capacitance) discharges. Therefore, the source and gate of the depletion-type n-channel MOSFET are at the same potential and a conductive channel exists between the source and drain. This conductive channel acts as a resistor whose size is determined based on the dimensions of the depletion-type n-channel MOSFET, thereby deactivating switch 320 (e.g., applying a turn-off strength between the gate and source of switch 320). The depletion-type n-channel MOSFET is deactivated when the on-off keying begins to turn on input switch 304 to initiate energy transfer, such that the equivalent capacitance C... G2 The voltage at 322 can be increased from 0 to the voltage required to reliably turn on switch 320.

[0038] When input switch 304 is turned on, diode D1 316 is reverse biased and diode D2 is forward biased, thereby causing the equivalent capacitance C to... G1 (For example, the gate capacitance of a depletion-type n-channel MOSFET) negative charge. When input switch 304 is off, diode D1 316 is forward biased and diode D2 316 is reverse biased, while the equivalent capacitance C G1 The charge and voltage are maintained in accordance with the discharge rate caused by a passive discharge element, such as resistor R1. Therefore, one switching cycle after another, the gate of the depletion-type n-channel MOSFET (passive turn-off device 318) is negatively pumped below its source potential to match the load of resistor R1, thereby deactivating the depletion-type n-channel MOSFET (passive turn-off device 318) and increasing the drive voltage of switch 320, which is then turned on. Once the on / off key switch activity is stopped to turn off input switch 304, resistor R1 discharges through the depletion-type n-channel MOSFET (passive turn-off device 318), causing the depletion-type n-channel MOSFET (passive turn-off device 318) to turn on and turn off switch 320.

[0039] Figure 4A An embodiment of a device 400 for operating switch 432 through a transformer 404 that serves as an isolation barrier is shown, and Figure 4B An embodiment of a device 400 for operating a switch 432 through a capacitive coupling device 456 that serves as an isolation barrier is shown. Figure 4A The transformer 404 includes a primary side 412 connected to the input side 402 of the device 400 and a secondary side 410 connected to the output side 406 of the device 400. Figure 4B The capacitive coupling device 456 in the device 400 includes one or more capacitors, such as a first capacitor 452 and a second capacitor 454 positioned between the input side 402 and the output side 406 of the device 400. These isolation barriers provide electrical isolation between the input side 402 and the output side 406 of the device 400.

[0040] Device 400 utilizes a voltage multiplier 414 (e.g., a Cocroft-Walton multiplier) as a voltage conversion device to convert energy (e.g., energy transferred from input source 416 through an isolation barrier to output side 406) from the input voltage at input side 402 into an output voltage to control switch 432. Voltage multiplier 414 includes one or more stages. Each stage includes a diode and a capacitor / capacitor (e.g., capacitor CP1 and diode D2 as a first stage, capacitor CP2 and diode D3 as a second stage, capacitor CP3 and diode D4 as a third stage, etc.). Voltage multiplier 414 converts the input voltage into an output voltage, which can be a voltage higher than the input voltage to turn on switch 432.

[0041] Device 400 may include one or more input switches located on input side 402, such as first input switch SW1A 418, second input switch SW1B 422, third input switch SW2A 420 and fourth input switch SW2B 424. These input switches are controlled by on / off key control to perform a series of switching cycles to transfer energy from input side 402 to output side 406 for controlling, for example, switching 432 on output side 406.

[0042] The input side 402 of the isolation barrier is driven in a push-pull manner (e.g., Figure 4A The primary side 412 of transformer 404 in the middle or Figure 4B The method of operating one or more input switches (using the input sides of the first capacitor 452 and the second capacitor 454 of the capacitive coupling device 456) is used. During the first phase of the switching cycle, input current flows from the top terminal of the isolation barrier (e.g., the connection on the input side 402 to the top terminal of the primary side 412 of the transformer 404, or the connection on the input side 402 to the first capacitor 452 of the capacitive coupling device 456) to the bottom terminal of the isolation barrier (e.g., the connection on the input side 402 to the bottom terminal of the primary side 412 of the transformer 404, or the connection on the input side 402 to the second capacitor 454 of the capacitive coupling device 456). Specifically, the top terminal is pulled up and the bottom terminal is pulled down. Capacitors CP1, CP3, and CP5 are charged through diodes D2, D4, and D6, while diodes D3 and D5 are reverse biased. During the second phase of the switching cycle, current flows from the bottom terminal of the isolation barrier to the top terminal. Specifically, the top terminal is pulled down and the bottom terminal is pulled up. Capacitors CP2 and CP4 are charged via diodes D3 and D5, while diodes D2, D4, and D6 are reverse biased. For symmetry, the duty cycle can be set to 50%. The switching frequency during each stage can be set to a value that will not cause the isolation barrier to reach / exceed saturation and / or cause reliability issues.

[0043] and Figure 3 Equipment 300 Figure 4A and Figure 4B The device 400 includes a switch 432, a passive turn-off device 428 (e.g., a depletion-type n-channel MOSFET), and an equivalent capacitance C located on the output side of the device 400. G2 430 (e.g., representation of the gate capacitance of switch 432) and charge pump 408, charge pump 408 including an equivalent capacitance C G1 For example, the gate capacitance of a depletion-type n-channel MOSFET, passive discharge elements such as resistor R1, and similar... Figure 3 The diode D2 in the device 400 is a diode D1. These components / elements of the device 400 can operate similarly to their corresponding components / elements of the device 300 in order to turn the switch 432 on and off.

[0044] The methods and apparatus provided herein enable control of switches, such as solid-state switches or other types of switches, across isolation barriers. Switches can be turned on and off without additional energy consumption on the output side of the isolation barrier where the switch is located. The isolation barrier provides electrical isolation between its input and output sides. Electrical isolation is provided without introducing topology differences or topology losses. Because devices with electrical isolation will have similar / identical dimensions, packages, and / or leads, easy replacement of these devices with other devices is possible. It is understood that these methods and apparatuses can be implemented for any type of device, such as computers, mobile devices, electronic devices, devices utilizing switches, etc.

[0045] Embodiments of this disclosure include a method. The method includes operating one or more input switches on the input side of an isolation device according to a frequency and duty cycle to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles for activating the switches, wherein a voltage conversion device converts energy from an input voltage on the input side into an output voltage to control the switches, and a passive shutdown device is prevented from deactivating the switches when energy transfer is valid, wherein the passive shutdown device passively deactivates the switches when energy transfer is invalid.

[0046] According to some implementations, the method includes: when energy transfer is effective, using a negative charge pump on the output side to actively drive the gate of a passive shutdown device downward with a negative voltage to prevent the passive shutdown device from activating the switch.

[0047] According to some implementations, a negative charge pump pumps the gate of a passive shutdown device to a position below the source of the passive shutdown device to deactivate the passive shutdown device, wherein a passive discharge element loads the negative charge pump to bring the source and gate to the same voltage.

[0048] According to some implementations, operating one or more input switches involves using on / off keying technology to perform multiple switching cycles to transfer energy through an isolation device for operating the switches.

[0049] According to some implementations, the passive shutdown device includes a depletion-type MOSFET.

[0050] According to some implementations, the voltage conversion device includes a voltage multiplier.

[0051] According to some implementations, the voltage conversion device includes a flyback converter.

[0052] According to some implementations, the voltage conversion device generates an output voltage higher than the input voltage.

[0053] According to some implementations, the isolation device includes a transformer.

[0054] According to some implementations, the isolation device includes a capacitive coupling device.

[0055] Implementations of the technology disclosed herein include an apparatus comprising means for operating one or more input switches on the input side of an isolation device according to a frequency and duty cycle to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles for activating the switches, wherein a voltage conversion device converts energy from an input voltage on the input side into an output voltage to control the switches, and wherein a passive shutdown device is prevented from deactivating the switches when energy transfer is valid, wherein the passive shutdown device passively deactivates the switches when energy transfer is invalid.

[0056] Embodiments of this disclosure include an apparatus. The apparatus includes: an energy transfer device configured to operate one or more input switches on the input side of an isolation device according to a frequency and duty cycle to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles for activating the switches; a voltage conversion device configured to convert energy from an input voltage on the input side to an output voltage to control the switches when energy transfer is active; a passive shutdown device configured to passively deactivate the switches when energy transfer is inactive; and a negative charge pump configured to prevent the passive shutdown device from deactivating the switches when energy transfer is active.

[0057] According to some implementations, the energy transfer device is located on the input side of the isolation device, and the passive shutdown device, negative charge pump, and switch are located on the output side of the isolation device.

[0058] According to some embodiments, the voltage conversion device includes a voltage multiplier, and the isolation device includes a transformer.

[0059] According to some embodiments, the voltage conversion device includes a voltage multiplier, and the isolation device includes a capacitive coupling device.

[0060] According to some embodiments, the voltage conversion device includes a flyback converter, and the isolation device includes a transformer.

[0061] According to some embodiments, the voltage conversion device includes a voltage multiplier, and the energy transfer device is configured to drive energy to the isolation device in a push-pull manner, wherein the switching cycle includes a first phase in which input current flows from the top terminal of the isolation device to the bottom terminal of the isolation device and a second phase in which input current flows from the bottom terminal to the top terminal.

[0062] Embodiments of this disclosure include an apparatus. The apparatus includes: an energy transfer device configured to operate one or more input switches on the input side of an isolation device to transfer energy through the isolation device to the output side of the isolation device for activating the switches; a voltage conversion device configured to convert energy from an input voltage on the input side to an output voltage to control the switches when energy transfer is valid; and a passive shutdown device configured to passively deactivate the switches when energy transfer is invalid, wherein the passive shutdown device is prohibited from deactivating the switches when energy transfer is valid.

[0063] According to some implementations, the isolation device provides current isolation between the input side and the output side.

[0064] According to some implementations, the energy transfer device is configured to operate a first switch, a second switch, a third switch, and a fourth switch to perform multiple switching cycles to transfer energy through an isolation device.

[0065] According to some embodiments, the voltage conversion device includes one or more stages, wherein each of the one or more stages includes a diode and a capacitor.

[0066] Although the subject matter has been described in language specific to structural features and / or methodological actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as exemplary forms of implementing the claims.

[0067] As used in this application, the terms "component," "module," "system," etc., are generally intended to refer to computer-related entities, hardware, combinations of hardware and software, software, or software in execution. One or more components may be located on a single computer and / or distributed among two or more computers.

[0068] Furthermore, the claimed subject matter can be implemented as a method, apparatus, or article of manufacture using standard programming and / or engineering techniques to produce software, firmware, hardware, or any combination thereof for controlling a computer to implement the disclosed subject matter. As used herein, the term "article of manufacture" is intended to include computer programs accessible from any computer-readable device, carrier, or medium. Of course, those skilled in the art will recognize that many modifications can be made to this configuration without departing from the scope or spirit of the claimed subject matter.

[0069] This document provides various operations for each implementation. In one implementation, one or more of the described operations may constitute computer-readable instructions stored on one or more computer-readable media, which, when executed by a computing device, would cause the computing device to perform the described operations. The order in which some or all of the operations are described should not be construed as implying that these operations must depend on a specific order. Alternative orderings will be understood by those skilled in the art who benefit from this specification. Furthermore, it will be understood that not all operations must be present in every implementation provided herein.

[0070] Any aspect or design described herein as an "example" is not necessarily to be construed as advantageous over other aspects or designs. Rather, the use of the word "example" is intended to illustrate one possible aspect and / or implementation that may relate to the technology presented herein. Such examples are not necessary for such technology or are not intended to be limiting. Various implementations of such technology may include such examples alone or in combination with other features, and / or the examples shown may be modified and / or omitted.

[0071] As used in this application, the term "or" is intended to mean inclusive "or" rather than exclusive "or". That is, unless otherwise specified or clear from the context, "X adopts A or B" is intended to mean any natural inclusive arrangement. That is, if X adopts A, X adopts B, or X adopts both A and B, then "X adopts A or B" is satisfied in any of the foregoing cases. Additionally, unless otherwise specified or clearly addressed to the singular form from the context, the articles "a" and "an" as used in this application and the appended claims should generally be interpreted as meaning "one or more". Furthermore, unless otherwise specified, "first", "second", etc., are not intended to imply temporal, spatial, or sequential aspects. Rather, such terms are used only as identifiers, names, etc., of features, elements, items, etc. For example, a first element and a second element generally correspond to element A and element B, or two different or two identical elements, or the same element.

[0072] Furthermore, while this disclosure has been shown and described with respect to one or more implementations, equivalent changes and modifications will occur to those skilled in the art based on a reading and understanding of this specification and the accompanying drawings. This disclosure includes all such modifications and changes and is defined only by the scope of the appended claims. In particular, with respect to the various functions performed by the components described above (e.g., elements, sources, etc.), unless otherwise indicated, the terminology used to describe such components is intended to correspond to any component that performs the specified function of the described component (e.g., a functionally equivalent component), even where the function performed in the example implementations shown herein is not structurally equivalent to the disclosed structure. Additionally, although a particular feature of this disclosure may be disclosed with respect to only one of several implementations, such features may be combined with one or more other features of other implementations as may be expected and advantageous for any given or particular application. Furthermore, with regard to the terms “includes,” “having,” “has,” “with,” or variations thereof used in the detailed description and claims, such terms are intended to be inclusive in a manner similar to the term “comprising.”

Claims

1. A control method, comprising: Based on frequency and duty cycle, on-off keying technology is used to operate one or more input switches on the input side of the isolation device through multiple switching cycles, so as to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles to activate the switches. The voltage conversion device converts the energy from the input voltage on the input side into an output voltage to control the switch. When energy transfer is effective, a negative charge pump at the output side uses a negative voltage to actively drive the gate of the passive shutdown device downwards, thereby preventing the passive shutdown device from activating the switch. Specifically, when energy transfer is invalid, the passive shutdown device passively deactivates the switch. In each of the plurality of switching cycles: The negative charge pump generates a negative voltage on the output side. Initiate the on / off keying process to drive the gate of the passive shutdown device below its source, thereby preventing the passive shutdown device from turning on; Stop the on / off key control process to release the negative voltage, thereby turning on the passive shutdown device.

2. The control method according to claim 1, wherein, The negative charge pump pumps the gate of the passive shutdown device to a position below the source of the passive shutdown device to deactivate the passive shutdown device, and wherein a passive discharge element loads the negative charge pump to bring the source and the gate to the same voltage.

3. The control method according to claim 1, wherein, The passive shutdown device includes a depletion-type MOSFET.

4. The control method according to claim 1, wherein, The voltage conversion device includes a voltage multiplier.

5. The control method according to claim 1, wherein, The voltage conversion device includes a flyback converter.

6. The control method according to claim 1, wherein, The voltage conversion device generates an output voltage that is higher than the input voltage.

7. The control method according to claim 1, wherein, The isolation device includes a transformer.

8. The control method according to claim 1, wherein, The isolation device includes a capacitive coupling device.

9. A control device, comprising: An energy transfer device is configured to operate one or more input switches on the input side of an isolation device by performing multiple switching cycles based on frequency and duty cycle using on-off keying technology, so as to transfer energy through the isolation device to the output side of the isolation device during a series of switching cycles for activating the switches; A voltage conversion device configured to convert the energy from an input voltage on the input side into an output voltage to control the switch when energy transfer is effective; A passive shutdown device configured to passively deactivate the switch when the energy transfer is invalid; as well as A negative charge pump is configured to actively drive the gate of the passive shutdown device downwards using a negative voltage when the energy transfer is active, thereby preventing the passive shutdown device from activating the switch. In each of the plurality of switching cycles: The negative charge pump generates a negative voltage on the output side. Initiate the on / off keying process to drive the gate of the passive shutdown device below its source, thereby preventing the passive shutdown device from turning on; Stop the on / off key control process to release the negative voltage, thereby turning on the passive shutdown device.

10. The control device according to claim 9, wherein, The energy transfer device is located on the input side of the isolation device, and the passive shutdown device, the negative charge pump, and the switch are located on the output side of the isolation device.

11. The control device according to claim 9, wherein, The voltage conversion device includes a voltage multiplier, and the isolation device includes a transformer.

12. The control device according to claim 9, wherein, The voltage conversion device includes a voltage multiplier, and the isolation device includes a capacitive coupling device.

13. The control device according to claim 9, wherein, The voltage conversion device includes a flyback converter, and the isolation device includes a transformer.

14. The control device according to claim 9, wherein, The voltage conversion device includes a voltage multiplier, and the energy transfer device is configured to: The energy is driven to the isolation device in a push-pull manner, wherein the switching cycle includes a first stage and a second stage, in which the input current flows from the top terminal of the isolation device to the bottom terminal of the isolation device; and in the second stage, the input current flows from the bottom terminal to the top terminal.

15. A control device, comprising: An energy transfer device is configured to operate one or more input switches on the input side of an isolation device by performing multiple switching cycles using on / off keying technology, so as to transfer energy through the isolation device to the output side of the isolation device for activating the switches; A voltage conversion device configured to convert the energy from an input voltage on the input side into an output voltage when energy transfer is effective, in order to control the switch; as well as A passive shutdown device configured to passively deactivate the switch when the energy transfer is invalid. Specifically, when the energy transfer is effective, a negative voltage is used to actively drive the gate of the passive shutdown device downwards, thereby preventing the passive shutdown device from activating the switch. In each of the plurality of switching cycles: A negative voltage is generated on the output side using a negative charge pump; Initiate the on / off keying process to drive the gate of the passive shutdown device below its source, thereby preventing the passive shutdown device from turning on; Stop the on / off key control process to release the negative voltage, thereby turning on the passive shutdown device.

16. The control device according to claim 15, wherein, The isolation device provides current isolation between the input side and the output side.

17. The control device according to claim 15, wherein, The energy transfer device is configured to operate a first switch, a second switch, a third switch, and a fourth switch to perform multiple switching cycles to transfer the energy through the isolation device.

18. The control device according to claim 15, wherein, The voltage conversion device includes one or more stages, wherein each of the one or more stages includes a diode and a capacitor.

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