Power management chip starting circuit and power management device

Abstract

The application discloses a power management chip starting circuit and a power management device. The power management chip starting circuit comprises a wake-up starting module and a switch module; a first input end and a third input end of the wake-up starting module are connected with a first power supply; an output end of the wake-up starting module is connected with a control end of the switch module; a first input end of the switch module is connected with the first power supply; an output end of the switch module is connected with a wake-up pin of a power management chip; a first power supply pin of the power management chip is connected with the first power supply; the wake-up starting module can control the switch module to be turned on when a voltage of the first power supply rises to be greater than or equal to a preset voltage value, so that the switch module outputs a starting signal to the wake-up pin of the power management chip, thereby making the power management chip switch from a fault safety mode to a normal working mode to ensure the continuous performance of normal starting, and thus the technical problem that the power management chip fails to start in a slow rising process of input power supply power-on is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power management chip, and particularly relates to a power management chip starting circuit and a power management device. BACKGROUND

[0002] In the process of continuous development of the vehicle industry, a power management system has become an important part of the vehicle control system. Generally, a power management chip has a function of monitoring and diagnosing the output voltage of itself, and the output voltage of the power management chip rises with the rise of the input power supply of the power management chip. Then, in the process of slow rise of the input power supply, if the output voltage of the power management chip does not exceed the under-voltage threshold voltage within a specified time (such as 3 ms) after power-on, the power management chip will diagnose itself as a short-circuit fault, and trigger the short-circuit protection mechanism of itself. Under the short-circuit protection mechanism, the state machine in the power management chip forces the power management chip to enter a failsafe mode, and after the power management chip enters the failsafe mode, all output voltages are turned off, thereby causing the power management chip to fail to start, and further causing the vehicle system to fail to work normally. SUMMARY

[0003] The present application provides a power management chip starting circuit and a power management device to solve the technical problem of the power management chip failing to start in the process of slow rise of the input power supply, and to ensure the normal start of the power management chip, and further ensure the normal work of the vehicle system.

[0004] According to an aspect of the present application, a power management chip starting circuit is provided, comprising: a wake-up starting module and a switch module.

[0005] The wake-up starting module comprises a first input end, a second input end, a third input end and an output end; the first input end of the wake-up starting module is connected to a first power supply, the second input end of the wake-up starting module is connected to a second power supply, and the third input end of the wake-up starting module is connected to the first power supply.

[0006] The switch module comprises a control end, a first input end, a second input end, a third input end and an output end; the control end of the switch module is connected to the output end of the wake-up starting module, the first input end of the switch module is connected to the first power supply, the second input end of the switch module is connected to the second power supply, the third input end of the switch module is connected to the second power supply, and the output end of the switch module is connected to a wake-up pin of a power management chip.

[0007] The first power pin of the power management chip is connected to the first power supply, and the second power pin of the power management chip is connected to the second power supply; the wake-up opening module is configured to control the switch module to be turned on when the voltage of the first power supply rises to be greater than or equal to a preset voltage value, so that the switch module outputs an opening signal to the wake-up pin, thereby enabling the power module chip to switch from a fail-safe mode to a normal working mode for normal startup.

[0008] Optionally, the wake-up closing module is further included.

[0009] The wake-up closing module includes a first input end, a second input end, a third input end and an output end.

[0010] The first input end of the wake-up closing module is connected to the output end of the wake-up opening module, the second input end of the wake-up closing module is connected to the first power supply, the third input end of the wake-up closing module is connected to the second power supply, and the output end of the wake-up closing module is connected to the control end of the switch module; the wake-up closing module is configured to control the switch module to be turned off after the wake-up pin receives the opening signal for a preset time period, so that the wake-up pin enters an initialization state.

[0011] Optionally, the wake-up opening module includes a first resistor, a second resistor, a first voltage stabilizing diode, a third resistor and a first triode.

[0012] The first end of the first resistor is connected to the first input end of the wake-up opening module, and the second end of the first resistor is connected to the second input end of the wake-up opening module.

[0013] The first end of the second resistor is connected to the first end of the first resistor, the second end of the second resistor is connected to the first pole of the first voltage stabilizing diode, and the second pole of the first voltage stabilizing diode is connected to the control pole of the first triode.

[0014] The first end of the third resistor is connected to the third input end of the wake-up opening module, the second end of the third resistor is connected to the first pole of the first triode, and the second pole of the first triode is connected to the second input end of the wake-up opening module.

[0015] Optionally, the switch module includes a second triode, a fourth resistor, a first diode, a fifth resistor and a sixth resistor.

[0016] The control electrode of the second triode is connected with the control end of the switch module, the first electrode of the second triode is connected with the first input end of the switch module, the second electrode of the second triode is connected with the first electrode of the first diode, the second electrode of the first diode is connected with the first end of the fifth resistor, and the second end of the fifth resistor is connected with the output end of the switch module.

[0017] The first end of the sixth resistor is connected with the second end of the fifth resistor, and the second end of the sixth resistor is connected with the third input end of the switch module; the first end of the fourth resistor is connected with the second input end of the switch module, and the second end of the fourth resistor is connected with the first electrode of the first diode.

[0018] Optionally, the control end of the switch module is connected with the output end of the wake-up opening module through a seventh resistor.

[0019] Optionally, the preset voltage value is greater than or equal to the sum of the conduction voltage of the first voltage stabilizing diode and the conduction voltage of the first triode.

[0020] Optionally, the wake-up closing module comprises a third triode, an eighth resistor, a ninth resistor, a fourth triode, a second voltage stabilizing diode, a fifth triode, a tenth resistor, a first capacitor and an eleventh resistor.

[0021] The first electrode of the third triode is connected with the second input end of the wake-up closing module, the second electrode of the third triode is connected with the output end of the wake-up closing module, the control electrode of the third triode is connected with the first end of the eighth resistor, the first end of the eighth resistor is connected with the first end of the ninth resistor, and the second end of the ninth resistor is connected with the first electrode of the third triode.

[0022] The first electrode of the fourth triode is connected with the first end of the ninth resistor, the second electrode of the fourth triode is connected with the third input end of the wake-up closing module, the control electrode of the fourth triode is connected with the first electrode of the second voltage stabilizing diode, the second electrode of the second voltage stabilizing diode is connected with the first end of the first capacitor, and the second end of the first capacitor is connected with the second electrode of the fourth triode.

[0023] The first end of the tenth resistor is connected with the first end of the first capacitor, the second end of the tenth resistor is connected with the second electrode of the fifth triode, the first electrode of the fifth triode is connected with the first electrode of the third triode, and the control electrode of the fifth triode is connected with the first input end of the wake-up closing module through the eleventh resistor.

[0024] Optionally, the preset time period is positively correlated with the time period for charging the first capacitor to the preset threshold voltage.

[0025] According to another aspect of the present application, there is provided a power management device comprising a power management chip and the power management chip starting circuit according to the above aspect.

[0026] Optionally, the switch module in the power management chip starting circuit comprises a second triode, a fourth resistor, a first diode, a fifth resistor and a sixth resistor; the control electrode of the second triode is connected with the control end of the switch module, the first electrode of the second triode is connected with the first input end of the switch module, the second electrode of the second triode is connected with the first electrode of the first diode, the second electrode of the first diode is connected with the first end of the fifth resistor, the second end of the fifth resistor is connected with the output end of the switch module; the first end of the sixth resistor is connected with the second end of the fifth resistor, the second end of the sixth resistor is connected with the third input end of the switch module; the first end of the fourth resistor is connected with the second input end of the switch module, the second end of the fourth resistor is connected with the first electrode of the first diode.

[0027] The power management device further comprises a second diode; the first electrode of the second diode is connected with a third power supply, and the second electrode of the second diode is connected with the second electrode of the first diode.

[0028] The technical scheme of the embodiment of the present application comprises the following steps: the first input end and the third input end of the wake-up starting module are connected with the first power supply, the second input end of the wake-up starting module is connected with the second power supply, the output end of the wake-up starting module is connected with the control end of the switch module, the first input end of the switch module is connected with the first power supply, the second input end and the third input end of the switch module are connected with the second power supply, the output end of the switch module is connected with the wake-up pin of the power management chip, the first power pin of the power management chip is connected with the first power supply, the second power pin of the power management chip is connected with the second power supply, and the wake-up starting module can control the switch module to be turned on when the voltage of the first power supply rises to be greater than or equal to the preset voltage value, so that the switch module outputs the starting signal to the wake-up pin of the power management chip, thereby making the power management chip switch from the fault safety mode to the normal working mode for normal starting, i.e., making the power management chip wake up from the fault safety mode and enter the normal working mode to ensure the continuous normal starting, and the first power supply is the input power supply. Thus, the technical problem of the power management chip failing to start during the slow rising process of the input power supply is solved, the normal starting of the power management chip is ensured, and the normal working of the vehicle-mounted system is ensured.

[0029] It is to be understood that the details set forth herein do not limit the scope of the embodiments of the application to the specific embodiments described. The foregoing detailed description has set forth various embodiments of the devices and / or processes via the use of specific terminology. However, embodiments of the application are not necessarily limited to those described, but can be practiced with the BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0031] Figure 1 is a structural schematic diagram of a power management chip starting circuit provided by an embodiment of the present application;

[0032] Figure 2 is a structural schematic diagram of another power management chip starting circuit provided by an embodiment of the present application;

[0033] Figure 3 is a structural schematic diagram of another power management chip starting circuit provided by an embodiment of the present application;

[0034] Figure 4 is a structural schematic diagram of another power management chip starting circuit provided by an embodiment of the present application;

[0035] Figure 5 is a structural schematic diagram of another power management chip starting circuit provided by an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the technical personnel in the art better understand the present application scheme, the following will combine the drawings in the embodiments of the present application, the technical solutions in the embodiments of the present application are described clearly and completely, obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0037] It should be noted that the terms "first", "second", and the like in the description and in the claims of the present application and the above-described accompanying drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus including a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products, or apparatuses.

[0038] Figure 1 is a structural schematic diagram of a power management chip starting circuit provided by an embodiment of the application, and Figure 1 The power management chip is also shown in the figure. Figure 1 The power management chip starting circuit comprises a wake-up starting module 100 and a switch module 200.

[0039] The wake-up starting module 100 comprises a first input end a1, a second input end b1, a third input end c1, and an output end d1. The first input end a1 of the wake-up starting module 100 is connected to the first power supply KL30, the second input end b1 of the wake-up starting module 100 is connected to the second power supply, and the third input end c1 of the wake-up starting module 100 is connected to the first power supply KL30.

[0040] The switch module 200 comprises a control end a2, a first input end b2, a second input end c2, a third input end d2, and an output end e2. The control end a2 of the switch module 200 is connected to the output end d1 of the wake-up starting module 100, the first input end b2 of the switch module 200 is connected to the first power supply KL30, the second input end c2 of the switch module 200 is connected to the second power supply, the third input end d2 of the switch module 200 is connected to the second power supply, and the output end e2 of the switch module 200 is connected to the wake-up pin ENA of the power management chip 400.

[0041] The first power supply pin VS of the power management chip 400 is connected to the first power supply KL30, and the second power supply pin GND of the power management chip 400 is connected to the second power supply. The wake-up starting module 100 is used to control the switch module 200 to be turned on when the voltage of the first power supply KL30 rises to be greater than or equal to a preset voltage value, so that the switch module 200 outputs a starting signal to the wake-up pin ENA, thereby making the power management chip 400 switch from a fault safety mode to a normal working mode for normal starting.

[0042] Specifically, the first power supply KL30 can be an input power supply, and the second power supply can be a 0V power supply. Exemplarily, the first power supply KL30 can have a size of 12V, and the technical solution of the embodiment of the application can be applicable to a vehicle-mounted 12V system. The wake-up starting module 100 can be composed of a plurality of conventional circuit components electrically connected with each other. The switch module 200 can be composed of a transistor and a plurality of conventional circuit components electrically connected with each other. The voltage of the first power supply pin VS of the power management chip 400 rises with the rise of the voltage of the first power supply KL30. The voltage of the first power supply KL30 greater than or equal to a preset voltage value can be used for the normal work of the power management chip 400. The working modes of the power management chip 400 include a sleep mode, a fault safety mode and a normal working mode. If the power management chip 400 is in the sleep mode, when the wake-up pin ENA is pulled from low to high, the power management chip 400 is switched from the sleep mode to the normal working mode. If the power management chip 400 is in the fault safety mode, the power module closes all output voltages, and when the wake-up pin ENA is pulled from low to high, the power management chip 400 is switched from the fault safety mode to the normal working mode.

[0043] The power management chip 400 has the function of monitoring and diagnosing the output voltage of itself. During the slow rise of the input power supply, if the output voltage of the power management chip 400 does not exceed the undervoltage threshold voltage within a specified time after power-on, the power management chip 400 will diagnose itself as a short-circuit fault, thereby triggering the short-circuit protection mechanism of itself. Under the short-circuit protection mechanism, the state machine inside the power management chip 400 forces the power management chip 400 to enter the fault safety mode. After the power management chip 400 enters the safety fault mode, all output voltages are closed, thereby causing the power management chip 400 to fail to start up, and further causing the vehicle-mounted system to be unable to work normally.

[0044] To this end, in the embodiment of the present application, the wake-up opening module 100 and the switch module 200 are arranged, the first input end a1 of the wake-up opening module 100 is connected to the first power supply KL30, the output end d1 of the wake-up opening module 100 is connected to the control end a2 of the switch module 200, the output end e2 of the switch module 200 is connected to the wake-up pin ENA of the power management chip 400, and the first power supply pin VS of the power management chip 400 is connected to the first power supply KL30. When the first power supply KL30 slowly rises to be greater than or equal to the preset voltage value, the wake-up opening module 100 controls the switch module 200 to be turned on, so that the switch module 200 outputs an opening signal to the wake-up pin ENA, the opening signal is, for example, a high level, and the wake-up pin ENA is pulled high (the effective wake-up signal of the wake-up pin ENA is a rising edge signal), so that the power management chip 400 is switched from the fault safety mode to the normal working mode, the power management chip 400 exits from the fault safety mode and enters the normal working mode, and all output voltages are no longer closed, and the normal starting can be continued. Thus, the technical problem that the power management chip 400 enters the fault safety mode due to the output voltage of the power management chip 400 not exceeding the under-voltage threshold voltage within the specified time after power-on in the process of slow rising of the first power supply KL30, and the power management chip 400 fails to start, is solved, the normal starting of the power management chip 400 is ensured, and then the normal working of the vehicle-mounted system is ensured. The embodiment of the present application can ensure the normal starting of the power management chip 400 based on the wake-up pin ENA of the power management chip 400, the starting circuit structure of the power management chip 400 is simple, easy to implement, and has strong practicability.

[0045] When the wake-up pin ENA is pulled high by the opening signal output by the switch module 200, it will always be in a pulled high state, so it will no longer be able to effectively identify other wake-up signals, such as a car key ignition signal. In order to solve the technical problem of the starting failure of the power management chip 400 in the process of slow rising of the input power supply, without affecting the identification and response of the wake-up pin ENA to other wake-up signals in the vehicle-mounted system, the power management chip 400 starting circuit provided by the embodiment of the present application further includes a wake-up closing module.

[0046] Figure 2 is another structure schematic diagram of a power management chip starting circuit provided by the embodiment of the present application. Referring to Figure 2 On the basis of the above technical solutions, as an embodiment of the present application, optionally, the power management chip starting circuit further includes: a wake-up closing module 300; the wake-up closing module 300 includes a first input end a3, a second input end b3, a third input end c3 and an output end d3.

[0047] The first input end of the wake-up closing module 300 is connected with the output end d1 of the wake-up opening module 100, the second input end of the wake-up closing module 300 is connected with the first power supply KL30, the third input end of the wake-up closing module 300 is connected with the second power supply, and the output end of the wake-up closing module 300 is connected with the control end a2 of the switch module 200; the wake-up closing module 300 is used for controlling the switch module 200 to be turned off after the wake-up pin ENA receives the opening signal for a preset time period, so that the wake-up pin ENA enters an initialization state.

[0048] Specifically, the wake-up pin ENA is arranged to keep receiving the opening signal for a preset time period, so as to ensure that the wake-up pin ENA is effectively pulled high, thereby ensuring that the power management chip 400 is effectively switched from the fault safety mode to the normal working mode. The switch module 200 is arranged to be turned off after the wake-up pin ENA receives the opening signal for a preset time period, so as to effectively pull the wake-up pin ENA low, thereby ensuring that the wake-up pin ENA effectively identifies and responds to other wake-up signals. On the basis of solving the technical problem that the power management chip 400 fails to start during a slow rising process on the input power supply, the identification and response of the wake-up pin ENA to other wake-up signals in the vehicle-mounted system are not affected. The initialization state of the wake-up pin ENA can be understood as a state of waiting to wake up, for example, a low-level state.

[0049] The technical scheme of the embodiment of the application, the specific circuit structures of the wake-up opening module 100, the switch module 200 and the wake-up closing module 300 can be various, which are exemplarily described below, but are not limited to the application.

[0050] Figure 3 is another structural schematic diagram of a power management chip starting circuit provided by the embodiment of the application. Referring to Figure 3 On the basis of the above technical scheme, as an embodiment of the application, the wake-up opening module 100 can optionally include a first resistor R1, a second resistor R2, a first voltage stabilizing diode W1, a third resistor R3 and a first triode T1.

[0051] The first end of the first resistor R1 is connected with the first input end a1 of the wake-up opening module 100, and the second end of the first resistor R1 is connected with the second input end b1 of the wake-up opening module 100.

[0052] The first end of the second resistor R2 is connected with the first end of the first resistor R1, the second end of the second resistor R2 is connected with the first pole (for example, the cathode) of the first voltage stabilizing diode W1, and the second pole (for example, the anode) of the first voltage stabilizing diode W1 is connected with the control pole (for example, the base) of the first triode T1.

[0053] The first end of the second resistor R3 is connected with the third input end c1 of the wake-up starting module 100, and the second end of the second resistor R3 is connected with the first pole (for example, the collector) of the first triode T1. The second pole (for example, the emitter) of the first triode T1 is connected with the second input end b1 of the wake-up starting module 100.

[0054] Specifically, the voltage of the first power supply KL30 slowly rises from 0V. When the voltage of the first power supply KL30 is greater than or equal to the sum of the conduction voltage of the first voltage stabilizing diode W1 and the conduction voltage of the first triode T1, the first triode T1 is turned on, so that the controllable switch module 200 is turned on. Alternatively, in the embodiment, the preset voltage value is greater than or equal to the sum of the conduction voltage of the first voltage stabilizing diode W1 and the conduction voltage of the first triode T1, and when the voltage of the first power supply KL30 is greater than or equal to the preset voltage value, the voltage of the first power supply KL30 can meet the requirement of the normal work of the power management chip 400. Generally, the conduction voltage of the first voltage stabilizing diode W1 is about 5.1V, and the conduction voltage of the first triode T1 is about 0.7V, so the preset voltage value can be set to 6V or above. The conduction voltage of the first triode T1 can be the voltage between the base B and the emitter E of the first triode T1.

[0055] Continuing to refer to Figure 3 On the basis of the above technical solutions, as an embodiment of the present application, the switch module 200 comprises: a second triode T2, a fourth resistor R4, a first diode D1, a fifth resistor R5 and a sixth resistor R6.

[0056] The control pole (for example, the base) of the second triode T2 is connected with the control end a2 of the switch module 200, the first pole (for example, the emitter) of the second triode T2 is connected with the first input end b2 of the switch module 200, the second pole (for example, the collector) of the second triode T2 is connected with the first pole (for example, the anode) of the first diode D1, the second pole (for example, the cathode) of the first diode D1 is connected with the first end of the fifth resistor R5, and the second end of the fifth resistor R5 is connected with the output end e2 of the switch module 200.

[0057] The first end of the sixth resistor R6 is connected with the second end of the fifth resistor R5, and the second end of the sixth resistor R6 is connected with the third input end d2 of the switch module 200. The first end of the fourth resistor R4 is connected with the second input end c2 of the switch module 200, and the second end of the fourth resistor R4 is connected with the first pole of the first diode D1.

[0058] Continuing to refer to Figure 3 Alternatively, the control end a2 of the switch module 200 is connected with the output end d1 of the wake-up starting module 100 through a seventh resistor R7.

[0059] Figure 4 is another structure diagram of a power management chip starting circuit provided by an embodiment of the present application. Referring to Figure 4 On the basis of the above technical solution, as an embodiment of the present application, optionally, the wake-up closing module 300 comprises a third transistor T3, an eighth resistor R8, a ninth resistor R9, a fourth transistor T4, a second voltage stabilizing diode W2, a fifth transistor T5, a tenth resistor R10, a first capacitor C1 and an eleventh resistor R11.

[0060] The first pole (for example, the emitter) of the third transistor T3 is connected with the second input end of the wake-up closing module 300, the second pole (for example, the collector) of the third transistor T3 is connected with the output end of the wake-up closing module 300, and the control pole (for example, the base) of the third transistor T3 is connected with the first end of the eighth resistor R8, the first end of the eighth resistor R8 is connected with the first end of the ninth resistor R9, and the second end of the ninth resistor R9 is connected with the first pole of the third transistor T3.

[0061] The first pole (for example, the collector) of the fourth transistor T4 is connected with the first end of the ninth resistor R9, the second pole (for example, the emitter) of the fourth transistor T4 is connected with the third input end of the wake-up closing module 300, and the control pole (for example, the base) of the fourth transistor T4 is connected with the first pole (for example, the anode) of the second voltage stabilizing diode W2, the second pole (for example, the cathode) of the second voltage stabilizing diode W2 is connected with the first end of the first capacitor C1, and the second end of the first capacitor C1 is connected with the second pole of the fourth transistor T4.

[0062] The first end of the tenth resistor R10 is connected with the first end of the first capacitor C1, the second end of the tenth resistor R10 is connected with the second pole (for example, the collector) of the fifth transistor T5, the first pole (for example, the emitter) of the fifth transistor T5 is connected with the first pole of the third transistor T3, and the control pole (for example, the base) of the fifth transistor T5 is connected with the first input end of the wake-up closing module 300 through the eleventh resistor R11.

[0063] On the basis of the above technical solution, as an embodiment of the present application, optionally, the length of the preset time period is positively correlated with the length of time for charging the first capacitor C1 to the preset threshold voltage. Specifically, when the first capacitor C1 is charged to the preset threshold voltage, for example, when the voltage of the first capacitor C1 is greater than the sum of the conduction voltage of the second voltage stabilizing diode W2 and the conduction voltage of the fourth transistor T4, the third transistor T3 is turned on, so as to control the switch module 200 to be turned off. Optionally, in the present embodiment, the preset time period is equal to the time for charging the first capacitor C1 to the preset threshold voltage.

[0064] The embodiment of the present application also provides a power management device, which comprises the power management chip 400 and the power management chip starting circuit according to any of the above embodiments. The power management chip device and the power management chip starting circuit provided by the embodiment of the present application belong to the same inventive concept, can realize the same technical effects, and the repeated contents will not be described here.

[0065] Figure 5 is another structural schematic diagram of the power management chip starting circuit provided by the embodiment of the present application. Referring to Figure 5 On the basis of the above technical solution, as an embodiment of the present application, optionally, in the power management chip starting circuit included in the power management device, the power management chip starting circuit further comprises: a second diode D2; a first pole (for example, an anode) of the second diode D2 is connected to a third power supply KL15, the third power supply KL15 is connected to other wake-up signals of the vehicle-mounted system, and a second pole (for example, a cathode) of the second diode D2 is connected to a second pole of the first diode D1 in the switch module 200.

[0066] The working principle of the power management chip 400 starting circuit of the embodiment of the present application will be described below. Figure 5 The working principle of the power management chip 400 starting circuit of the embodiment of the present application will be described below.

[0067] When the voltage of the first power supply KL30 is greater than the sum of the conduction voltage of the first voltage stabilizing diode W1 and the conduction voltage of the first triode T1 (at this time, the power management chip 400 can be in a failsafe mode or a normal working mode), the first triode T1 is turned on, and then the second triode T2 is also turned on, and an output start signal is output, so that the first power supply KL30 pulls up the wake-up pin ENA of the power management chip 400, to ensure that the power management chip 400 is in a normal working mode, thereby ensuring that the power management chip 400 is started normally. When the first triode T1 is turned on, the fifth triode T5 is also turned on, and the first capacitor C1 starts to charge. When the voltage of the first capacitor C1 is greater than the sum of the conduction voltage of the second voltage stabilizing diode W2 and the conduction voltage of the fourth triode T4, the fifth triode T5 is turned on, and then the third triode T3 is turned on. The third triode T3 is turned on to turn off the second triode T2, so that the wake-up pin ENA becomes low, so that the wake-up pin ENA will not affect the effective identification of other wake-up signals of the vehicle-mounted system. Among them, the first capacitor C1 needs a certain time to charge to a preset threshold voltage, so the conduction of the second triode T2 is earlier than the conduction of the third triode T3. The conduction of the second triode T2 will wake up the wake-up pin ENA of the power management chip 400. After the third triode T3 is turned on to turn off the second triode T2, the second triode T2 is turned off, and the wake-up pin ENA of the power management chip 400 changes from high to low.

[0068] The above detailed description does not limit the scope of the application. Various modifications, combinations, sub-combinations and alternatives can be made to the detailed description. Any modification, equivalent replacement and improvement etc. made within the spirit and principle of the application shall be included in the scope of the application.

Claims

1. A power management chip start-up circuit, comprising: include: Wake up the power-on module and the switch module; The wake-up activation module includes a first input terminal, a second input terminal, a third input terminal, and an output terminal; the first input terminal of the wake-up activation module is connected to a first power supply, the second input terminal of the wake-up activation module is connected to a second power supply, and the third input terminal of the wake-up activation module is connected to the first power supply. The switch module includes a control terminal, a first input terminal, a second input terminal, a third input terminal, and an output terminal; the control terminal of the switch module is connected to the output terminal of the wake-up activation module, the first input terminal of the switch module is connected to the first power supply, the second input terminal of the switch module is connected to the second power supply, the third input terminal of the switch module is connected to the second power supply, and the output terminal of the switch module is connected to the wake-up pin of the power management chip. The first power pin of the power management chip is connected to the first power supply, and the second power pin of the power management chip is connected to the second power supply; the wake-up activation module is used to control the switch module to conduct when the voltage of the first power supply rises to a value greater than or equal to a preset voltage value, so that the switch module outputs an activation signal to the wake-up pin, thereby enabling the power management chip to switch from the fail-safe mode to the normal working mode for normal startup; The power management chip startup circuit also includes: a wake-up shutdown module; The wake-up shutdown module includes a first input terminal, a second input terminal, a third input terminal, and an output terminal; The first input terminal of the wake-up shutdown module is connected to the output terminal of the wake-up enable module, the second input terminal of the wake-up shutdown module is connected to the first power supply, the third input terminal of the wake-up shutdown module is connected to the second power supply, and the output terminal of the wake-up shutdown module is connected to the control terminal of the switch module. The wake-up shutdown module is used to control the switch module to turn off after the wake-up pin receives the enable signal for a preset time period, so that the wake-up pin enters the initialization state. The wake-up shutdown module includes: a third transistor, an eighth resistor, a ninth resistor, a fourth transistor, a second Zener diode, a fifth transistor, a tenth resistor, a first capacitor, and an eleventh resistor; The first terminal of the third transistor is connected to the second input terminal of the wake-up shutdown module, the second terminal of the third transistor is connected to the output terminal of the wake-up shutdown module, the control terminal of the third transistor is connected to the first terminal of the eighth resistor, the first terminal of the eighth resistor is connected to the first terminal of the ninth resistor, and the second terminal of the ninth resistor is connected to the first terminal of the third transistor. The first terminal of the fourth transistor is connected to the first terminal of the ninth resistor, the second terminal of the fourth transistor is connected to the third input terminal of the wake-up shutdown module, the control terminal of the fourth transistor is connected to the first terminal of the second Zener diode, the second terminal of the second Zener diode is connected to the first terminal of the first capacitor, and the second terminal of the first capacitor is connected to the second terminal of the fourth transistor. The first end of the tenth resistor is connected with the first end of the first capacitor, the second end of the tenth resistor is connected with the second electrode of the fifth triode, the first electrode of the fifth triode is connected with the first electrode of the third triode, and the control electrode of the fifth triode is connected with the first input end of the wake-up closing module through the eleventh resistor.

2. The power management chip start-up circuit of claim 1, wherein, The wake-up opening module comprises a first resistor, a second resistor, a first voltage stabilizing diode, a third resistor and a first triode. The first end of the first resistor is connected with the first input end of the wake-up opening module, and the second end of the first resistor is connected with the second input end of the wake-up opening module. The first end of the second resistor is connected with the first end of the first resistor, the second end of the second resistor is connected with the first electrode of the first voltage stabilizing diode, and the second electrode of the first voltage stabilizing diode is connected with the control electrode of the first triode. The first end of the third resistor is connected with the third input end of the wake-up opening module, the second end of the third resistor is connected with the first electrode of the first triode, and the second electrode of the first triode is connected with the second input end of the wake-up opening module.

3. The power management chip start-up circuit of claim 1, wherein, The switch module comprises a second triode, a fourth resistor, a first diode, a fifth resistor and a sixth resistor. The control electrode of the second triode is connected with the control end of the switch module, the first electrode of the second triode is connected with the first input end of the switch module, the second electrode of the second triode is connected with the first electrode of the first diode, the second electrode of the first diode is connected with the first end of the fifth resistor, and the second end of the fifth resistor is connected with the output end of the switch module. The first end of the sixth resistor is connected with the second end of the fifth resistor, and the second end of the sixth resistor is connected with the third input end of the switch module; the first end of the fourth resistor is connected with the second input end of the switch module, and the second end of the fourth resistor is connected with the first electrode of the first diode.

4. The power management chip start-up circuit of claim 1, wherein, The control end of the switch module is connected with the output end of the wake-up opening module through a seventh resistor.

5. The power management chip start-up circuit of claim 2, wherein, The preset voltage value is greater than or equal to the sum of the conduction voltage of the first voltage stabilizing diode and the conduction voltage of the first triode.

6. The power management chip start-up circuit of claim 1, wherein, The length of the preset time period is positively correlated with the length of time for charging the first capacitor to the preset threshold voltage.

7. A power management device, characterized by, The power management chip and the power management chip starting circuit according to any one of claims 1-6 are included.

8. The power management device of claim 7, wherein, The switch module in the power management chip starting circuit comprises a second triode, a fourth resistor, a first diode, a fifth resistor and a sixth resistor; the control electrode of the second triode is connected with the control end of the switch module, the first electrode of the second triode is connected with the first input end of the switch module, the second electrode of the second triode is connected with the first electrode of the first diode, the second electrode of the first diode is connected with the first end of the fifth resistor, the second end of the fifth resistor is connected with the output end of the switch module; the first end of the sixth resistor is connected with the second end of the fifth resistor, the second end of the sixth resistor is connected with the third input end of the switch module; the first end of the fourth resistor is connected with the second input end of the switch module, and the second end of the fourth resistor is connected with the first electrode of the first diode. The power management device further comprises a second diode; the first electrode of the second diode is connected with a third power supply, and the second electrode of the second diode is connected with the second electrode of the first diode.

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