Primary side information detection circuit, method and chip of secondary side PD controller

Abstract

The present application provides a primary side information detection circuit, method and chip of a secondary side PD controller, the circuit includes a first acquisition module, a second acquisition module, a first comparator, an adder, a switch module and a controller, the first acquisition module is used to collect VBUS voltage, the second acquisition module is used to collect VD platform voltage, and the first acquisition module and the second acquisition module have the same sampling ratio; when the VD platform voltage is greater than the sum of the VBUS voltage and the configured bias voltage, the first comparator is used to output a drive signal to the switch module to drive the switch module to turn on; the switch module is used to generate an output signal according to the VD platform voltage in different on and off states; the controller is used to determine the primary side information according to the pulse width and pulse strength of the output signal. The present application has the advantages of simple circuit structure, flexible configuration, high sampling accuracy and low cost.

Description

Technical Field

[0001] The present application relates to the technical field of primary side information detection, and in particular to a primary side information detection circuit, method and chip of a secondary side PD controller. Background Art

[0002] The secondary side PD controller is usually used to control the power transistor connected to the secondary coil of the power system to control the output voltage on the secondary coil. In the application, it is necessary to detect the switching frequency, on-time, off-time and effective value of the line voltage of the primary side controller.

[0003] However, in the prior art, the circuits used in detecting the primary side information are relatively complex, the detection cost is high, and the detection accuracy is low.

[0004] In summary, the prior art has the problem that the primary side information detection circuit is complex and the detection cost is high. Summary of the invention

[0005] The purpose of the present application is to provide a primary side information detection circuit, method and chip for a secondary side PD controller to solve the problems of complex primary side information detection circuit and high detection cost in the prior art.

[0006] In order to achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

[0007] In a first aspect, an embodiment of the present application provides a primary side information detection circuit of a secondary side PD controller, the circuit comprising a first acquisition module, a second acquisition module, a first comparator, an adder, a switch module and a controller, the first acquisition module is electrically connected to the adder, the adder is also electrically connected to the first input end of the first comparator, the second acquisition module is electrically connected to the second input end of the first comparator, the output end of the first comparator is electrically connected to the switch module, and the switch module is also electrically connected to the second acquisition module and the controller respectively; wherein,

[0008] The first acquisition module is used to acquire the VBUS voltage, the second acquisition module is used to acquire the VD platform voltage, and the first acquisition module and the second acquisition module have the same sampling ratio;

[0009] The adder is used for adding the VBUS voltage and the configured bias voltage and outputting the resultant to the first comparator;

[0010] When the VD platform voltage is greater than the sum of the VBUS voltage and the configured bias voltage, the first comparator is used to output a driving signal to the switch module to drive the switch module to turn on;

[0011] The switch module is used to generate an output signal according to the VD platform voltage in different on and off states;

[0012] The controller is used to determine the primary side information according to the pulse width and pulse strength of the output signal.

[0013] Optionally, the first acquisition module includes an acquisition unit and a filtering unit, the acquisition unit is electrically connected to the first input terminal of the adder, and the input terminal of the acquisition unit is also grounded through the filtering unit, the acquisition unit is used to acquire the VBUS voltage, the second input terminal of the adder is used to receive the configured bias voltage, and the output terminal of the adder is electrically connected to the first input terminal of the first comparator; wherein,

[0014] The adder is used for adding the VBUS voltage and the configured bias voltage and outputting the resultant sum to the first input terminal of the comparator.

[0015] Optionally, the acquisition unit includes a first resistor and a second resistor, one end of the first resistor and the second resistor connected in series is connected to the main circuit to collect the VBUS voltage, and the other end is grounded, and the first input end of the adder is connected between the first resistor and the second resistor.

[0016] Optionally, the primary side information detection circuit of the secondary side PD controller further includes a second comparator, a first input end of the second comparator is used to receive a preset voltage, a second input end of the second comparator is electrically connected to the second acquisition module, and an output end of the second comparator is electrically connected to the second input end of the adder; wherein,

[0017] The second comparator is used for generating a bias voltage, and transmitting the bias voltage to the second input terminal of the adder.

[0018] Optionally, the second acquisition module includes a third resistor and a fourth resistor, one end of the third resistor and the fourth resistor connected in series is used to collect the VD platform voltage, and the other end is grounded, and the second input end of the first comparator and the switch module are both connected between the third resistor and the fourth resistor.

[0019] Optionally, the switch module includes a transmission gate, a gate of the transmission gate is electrically connected to the output end of the first comparator, an input end of the transmission gate is electrically connected to the second acquisition module, and an output end of the transmission gate is electrically connected to the controller.

[0020] Optionally, the primary side information detection circuit of the secondary side PD controller also includes a first capacitor, a second capacitor, a buffer and a fifth resistor, one end of the buffer and the first capacitor are electrically connected to the switching module, the other end of the first capacitor is grounded, the other end of the buffer is electrically connected to one end of the fifth resistor, the other end of the fifth resistor is electrically connected to the controller, and the other end of the fifth resistor is grounded through the second capacitor.

[0021] In a second aspect, an embodiment of the present application further provides a detection chip, wherein the detection chip includes the primary side information detection circuit of the secondary side PD controller mentioned above.

[0022] In a third aspect, an embodiment of the present application further provides a primary side information detection method of a secondary side PD controller, which is applied to the primary side information detection circuit of the secondary side PD controller, and the method includes:

[0023] Collect VBUS voltage and VD platform voltage;

[0024] Generate an output signal according to the sum of the VBUS voltage and the configured bias voltage and the VD platform voltage;

[0025] The original side information is determined according to the pulse width and pulse strength of the output signal.

[0026] Optionally, the step of generating an output signal according to the sum of the VBUS voltage and the configured bias voltage and the VD platform voltage includes:

[0027] An adder is used to add the VBUS voltage and the configured bias voltage to generate an output signal with the VD platform voltage; wherein the configured bias voltage is generated according to the VD platform voltage and a preset voltage.

[0028] Compared with the prior art, this application has the following beneficial effects:

[0029] The present application provides a primary side information detection circuit, method and chip of a secondary side PD controller, the circuit includes a first acquisition module, a second acquisition module, a first comparator, an adder, a switch module and a controller, the first acquisition module is electrically connected to the adder, the adder is also electrically connected to the first input end of the first comparator, the second acquisition module is electrically connected to the second input end of the first comparator, the output end of the first comparator is electrically connected to the switch module, and the switch module is also electrically connected to the second acquisition module and the controller respectively; wherein the first acquisition module is used to collect VBUS voltage, the second acquisition module is used to collect VD platform voltage, and the sampling ratio of the first acquisition module and the second acquisition module is the same; the adder is used to add the VBUS voltage and the configured bias voltage and then output it to the first comparator, when the VD platform voltage is greater than the sum of the VBUS voltage and the configured bias voltage, the first comparator is used to output a drive signal to the switch module to drive the switch module to turn on; the switch module is used to generate an output signal according to the VD platform voltage in different on and off states; the controller is used to determine the primary side information according to the pulse width and pulse strength of the output signal. Since the circuit module provided by the present application is relatively simple, its cost is relatively low. In addition, by collecting and comparing the sum of the VD platform voltage, the VBUS voltage and the configured bias voltage, the original side information can be determined with higher accuracy.

[0030] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A system block diagram of a secondary-side PD controller in the prior art is shown.

[0033] Figure 2 A schematic diagram of a secondary side VDS waveform in the prior art is shown.

[0034] Figure 3 A module schematic diagram of a primary side information detection circuit of a secondary side PD controller provided in an embodiment of the present application is shown.

[0035] Figure 4 A circuit diagram of a primary side information detection circuit of a secondary side PD controller provided in an embodiment of the present application is shown.

[0036] Figure 5 An exemplary flow chart of a primary side information detection method of a secondary side PD controller provided in an embodiment of the present application is shown.

[0037] In the figure:

[0038] 110 - first acquisition module; 120 - second acquisition module; 130 - adder; 140 - first comparator; 150 - switch module; 160 - controller; 170 - second comparator. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0041] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0042] It should be noted that, in this document, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0043] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0044] As described in the background technology, the secondary side PD controller is generally used to control the power transistor connected to the secondary coil of the power system to control the output voltage on the secondary coil. In the application, the system diagram of the secondary side PD controller is as shown in FIG. Figure 1 shown.

[0045] like Figure 1As shown, the secondary-side PD controller is connected to the secondary coil, and controls the on-off state and on-off frequency of the power transistor on the main circuit by obtaining information on the secondary coil, thereby controlling the output voltage on the secondary coil.

[0046] However, the current related detection circuits are relatively complex. In view of this, an embodiment of the present application provides a primary side information detection circuit for a secondary side PD controller, which realizes the detection of primary side information through a relatively simple circuit structure, thereby reducing costs.

[0047] The primary side information detection circuit of the secondary side PD controller provided by the present application is exemplarily described below:

[0048] As an alternative implementation, see Figure 2 The circuit includes a first acquisition module 110, a second acquisition module 120, a first comparator 140, an adder 130, a switch module 150 and a controller 160. The first acquisition module 110 is electrically connected to the adder 130, and the adder 130 is also electrically connected to the first input end of the first comparator 140. The second acquisition module 120 is electrically connected to the second input end of the first comparator 140. The output end of the first comparator 140 is electrically connected to the switch module 150, and the switch module 150 is also electrically connected to the second acquisition module 120 and the controller 160 respectively; wherein the first acquisition module 110 is used to collect VBUS voltage, and the second acquisition module Block 120 is used to collect the VD platform voltage, and the sampling ratio of the first acquisition module 110 is the same as that of the second acquisition module 120; the adder 130 is used to add the VBUS voltage and the configured bias voltage and output it to the first comparator 140. When the VD platform voltage is greater than the sum of the VBUS voltage and the configured bias voltage, the first comparator 140 is used to output a drive signal to the switch module 150 to drive the switch module 150 to turn on; the switch module 150 is used to generate an output signal according to the VD platform voltage in different on and off states; the controller 160 is used to determine the primary side information according to the pulse width and pulse strength of the output signal.

[0049] The VD platform voltage described in this application refers to the voltage on the secondary side of the transformer, and it satisfies the formula:

[0050] VD platform voltage = VBUS + VIN / NPS;

[0051] Among them, VBUS voltage represents the secondary output voltage, VIN is the equivalent value of the primary output AC power supply voltage, and NPS is the primary-to-secondary turns ratio of the transformer.

[0052] Since the second acquisition module 120 can acquire the VD platform voltage, the first acquisition module 110 can acquire the VBUS voltage and drive the switch module 150 to be turned on by comparison. When the switch module 150 is turned on, the second acquisition module 120 can output the VD platform voltage to the controller 160; when the switch module 150 is turned off, the second acquisition module 120 cannot output the VD platform voltage to the controller 160, so that the output signal through the switch module 150 is actually a continuous pulse signal.

[0053] Since the output signal is directly related to the VD platform voltage, and the voltage frequency remains unchanged after the transformer transformation, only the voltage magnitude changes. On this basis, the frequency, on-time, off-time and primary voltage of the switch signal of the primary controller 160 can be determined according to the pulse width and pulse strength (pulse strength represents the voltage value) of the output signal, providing the secondary side main controller 160 with complete primary side information, thereby meeting the system decision-making requirements of the main controller 160.

[0054] In normal operation, the VDS waveform on the SR (secondary) side changes according to the effective value of the line voltage VIN and the load, such as Figure 3 As shown in the figure, VIN is the equivalent value of the primary output AC power supply voltage, and NPS is the primary-to-secondary turns ratio of the transformer. Since the VDS waveform changes with the effective value of VIN and the switching frequency, and there will be a resonant sine waveform that interferes with the correct sampling of line voltage information, in order to detect the primary controller switching frequency and the effective value of the line voltage from the SR (secondary) side VDS waveform, it is necessary to take a suitable comparison threshold to compare with this waveform, and at the same time, the platform voltage of the VDS waveform is required.

[0055] Therefore, as an implementation, see Figure 4 The first acquisition module 110 includes an acquisition unit and a filtering unit. The acquisition unit is electrically connected to the first input terminal of the adder 130, and the input terminal of the acquisition unit is also grounded through the filtering unit. The acquisition unit is used to acquire the VBUS voltage. The second input terminal of the adder 130 is used to receive the bias voltage. The output terminal of the adder 130 is electrically connected to the first input terminal of the first comparator 140; wherein the adder 130 is used to add the VBUS voltage and the bias voltage and output them to the first input terminal of the comparator. The filtering unit can be a capacitor, and the filtering function of the VBUS voltage is realized by the capacitor.

[0056] In addition, the primary side information detection circuit of the secondary side PD controller 160 also includes a second comparator 170, the first input end of the second comparator 170 is used to receive a preset voltage, the second input end of the second comparator 170 is electrically connected to the second acquisition module 120, and the output end of the second comparator 170 is electrically connected to the second input end of the adder 130; wherein the second comparator 170 is used to generate a bias voltage and transmit the bias voltage to the second input end of the adder 130.

[0057] The acquisition unit includes a first resistor and a second resistor, one end of the first resistor and the second resistor connected in series is connected to the main circuit to collect the VBUS voltage, and the other end is grounded, and the first input end of the adder 130 is connected between the first resistor and the second resistor. The sampling ratio of the present application is 50:1.

[0058] The second acquisition module 120 includes a third resistor and a fourth resistor, one end of the third resistor and the fourth resistor connected in series is used to collect the VD platform voltage, and the other end is grounded, and the second input end of the first comparator 140 and the switch module 150 are both connected between the third resistor and the fourth resistor.

[0059] The switch module 150 includes a transmission gate, a gate of the transmission gate is electrically connected to the output end of the first comparator 140 , an input end of the transmission gate is electrically connected to the second acquisition module 120 , and an output end of the transmission gate is electrically connected to the controller 160 .

[0060] The primary side information detection circuit of the secondary side PD controller 160 also includes a first capacitor, a second capacitor, a buffer and a fifth resistor. One end of the buffer and the first capacitor are electrically connected to the switch module 150, the other end of the first capacitor is grounded, the other end of the buffer is electrically connected to one end of the fifth resistor, the other end of the fifth resistor is electrically connected to the controller 160, and the other end of the fifth resistor is grounded through the second capacitor.

[0061] Therefore, the working principle of this application is:

[0062] The VBUS voltage is sampled through a 10:1 resistor network and then a 5:1 ratio circuit is used to obtain a 1 / 50 VBUS voltage. The voltage is added to the high-side bias voltage OS_HS to obtain TH_HS, which is compared with the VD voltage to obtain the VDS ON Signal. The VDS frequency can be calculated from the interval between the two ON Signals. After the ON Signal is delayed by BlankingTime, the VD platform voltage VBUS+VIN / NPS is sampled through the transmission gate TG1. The sampled VD platform voltage is stored in the second capacitor through the Buffer. The system calculates the original line voltage value based on the output voltage. In addition, the VDS on-time and off-time signals are obtained from the high-side comparator, from which the on-time of the VDS signal can be calculated. The off-time of the VDS signal can be obtained from the timing from the VDS off-time signal to the first rising edge of the fixed voltage comparator.

[0063] Based on the above implementation, an embodiment of the present application further provides a detection chip, which includes the above primary side information detection circuit.

[0064] Also, see Figure 5 The embodiment of the present application further provides a primary side information detection method of the secondary side PD controller 160, the method comprising:

[0065] S102, collecting VBUS voltage and VD platform voltage.

[0066] S104 , generating an output signal according to the sum of the VBUS voltage and the configured bias voltage and the VD platform voltage.

[0067] S106, determining the original side information according to the pulse width and pulse strength of the output signal.

[0068] Optionally, S104 includes:

[0069] An adder is used to add the VBUS voltage and the configured bias voltage to generate an output signal with the VD platform voltage; wherein the configured bias voltage is generated based on the VD platform voltage and the preset voltage.

[0070] The following is an exemplary description of the high voltage input protection circuit provided by the present application:

[0071] In summary, the present application provides a primary side information detection circuit, method and chip of a secondary side PD controller, the circuit includes a first acquisition module, a second acquisition module, a first comparator, an adder, a switch module and a controller, the first acquisition module is electrically connected to the adder, the adder is also electrically connected to the first input end of the first comparator, the second acquisition module is electrically connected to the second input end of the first comparator, the output end of the first comparator is electrically connected to the switch module, and the switch module is also electrically connected to the second acquisition module and the controller respectively; wherein the first acquisition module is used to collect VBUS voltage, the second acquisition module is used to collect VD platform voltage, and the sampling ratio of the first acquisition module and the second acquisition module is the same; the adder is used to add the VBUS voltage and the configured bias voltage and then output it to the first comparator, when the VD platform voltage is greater than the sum of the VBUS voltage and the configured bias voltage, the first comparator is used to output a drive signal to the switch module to drive the switch module to turn on; the switch module is used to generate an output signal according to the VD platform voltage in different on and off states; the controller is used to determine the primary side information according to the pulse width and pulse strength of the output signal. Since the circuit module provided by the present application is relatively simple, its cost is relatively low. In addition, by collecting and comparing the sum of the VD platform voltage, the VBUS voltage and the configured bias voltage, the primary side information can be determined with higher accuracy.

[0072] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0073] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above, and that the present application can be implemented in other specific forms without departing from the spirit or essential features of the present application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present application. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A primary side information detection circuit of a secondary side PD controller, characterized in that: The circuit includes a first acquisition module, a second acquisition module, a first comparator, an adder, a switch module and a controller, wherein the first acquisition module is electrically connected to the adder, and the adder is also electrically connected to the first input end of the first comparator, the second acquisition module is electrically connected to the second input end of the first comparator, the output end of the first comparator is electrically connected to the switch module, and the switch module is also electrically connected to the second acquisition module and the controller respectively; wherein, The first acquisition module is used to acquire the VBUS voltage, the second acquisition module is used to acquire the VD platform voltage, and the first acquisition module and the second acquisition module have the same sampling ratio; The adder is used for adding the VBUS voltage and the configured bias voltage and outputting the resultant to the first comparator; When the VD platform voltage is greater than the sum of the VBUS voltage and the configured bias voltage, the first comparator is used to output a driving signal to the switch module to drive the switch module to turn on; The switch module is used to generate an output signal according to the VD platform voltage in different on and off states; The controller is used to determine the original side information according to the pulse width and pulse strength of the output signal; The primary side information detection circuit of the secondary side PD controller further includes a second comparator, a first input end of the second comparator is used to receive a preset voltage, a second input end of the second comparator is electrically connected to the second acquisition module, and an output end of the second comparator is electrically connected to the second input end of the adder; wherein, The second comparator is used for generating a bias voltage, and transmitting the bias voltage to the second input terminal of the adder.

2. The primary side information detection circuit of the secondary side PD controller according to claim 1, characterized in that: The first acquisition module includes an acquisition unit and a filtering unit, the acquisition unit is electrically connected to the first input end of the adder, and the input end of the acquisition unit is also grounded through the filtering unit, the acquisition unit is used to acquire the VBUS voltage, the second input end of the adder is used to receive the configured bias voltage, and the output end of the adder is electrically connected to the first input end of the first comparator; wherein, The adder is used for adding the VBUS voltage and the configured bias voltage and outputting the resultant sum to the first input terminal of the comparator.

3. The primary side information detection circuit of the secondary side PD controller according to claim 2, characterized in that: The acquisition unit includes a first resistor and a second resistor, one end of the first resistor and the second resistor connected in series is connected to the main circuit to collect the VBUS voltage, and the other end is grounded, and the first input end of the adder is connected between the first resistor and the second resistor.

4. The primary side information detection circuit of the secondary side PD controller according to claim 1, characterized in that: The second acquisition module includes a third resistor and a fourth resistor, one end of the third resistor and the fourth resistor connected in series is used to collect the VD platform voltage, and the other end is grounded, and the second input end of the first comparator and the switch module are both connected between the third resistor and the fourth resistor.

5. The primary side information detection circuit of the secondary side PD controller according to claim 1, characterized in that: The switch module includes a transmission gate, a gate of the transmission gate is electrically connected to the output end of the first comparator, an input end of the transmission gate is electrically connected to the second acquisition module, and an output end of the transmission gate is electrically connected to the controller.

6. The primary side information detection circuit of the secondary side PD controller according to claim 1, characterized in that: The primary side information detection circuit of the secondary side PD controller also includes a first capacitor, a second capacitor, a buffer and a fifth resistor, one end of the buffer and the first capacitor are electrically connected to the switch module, the other end of the first capacitor is grounded, the other end of the buffer is electrically connected to one end of the fifth resistor, the other end of the fifth resistor is electrically connected to the controller, and the other end of the fifth resistor is grounded through the second capacitor.

7. A detection chip, characterized in that: The detection chip comprises a primary side information detection circuit of a secondary side PD controller as claimed in any one of claims 1 to 6.

8. A primary side information detection method of a secondary side PD controller, characterized in that: The primary side information detection circuit applied to the secondary side PD controller according to any one of claims 1 to 6, the method comprising: Collect VBUS voltage and VD platform voltage; Generate an output signal according to the sum of the VBUS voltage and the configured bias voltage and the VD platform voltage; The original side information is determined according to the pulse width and pulse strength of the output signal.

9. The primary side information detection method of the secondary side PD controller according to claim 8, characterized in that: The step of generating an output signal according to the sum of the VBUS voltage and the configured bias voltage and the VD platform voltage comprises: An adder is used to add the VBUS voltage and the configured bias voltage to generate an output signal with the VD platform voltage; wherein the configured bias voltage is generated according to the VD platform voltage and a preset voltage.

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