TWI898180B - Power integrated circuit, control intergrated circuit and circuit monitoring method - Google Patents

Abstract

A power supply integrated circuit, a control integrated circuit and a circuit monitoring method are provided. The power supply integrated circuit includes a monitoring circuit, a first information generating circuit and a first switching circuit. The monitoring circuit monitors the power supply integrated circuit and provides at least one monitoring signal and a first switching signal. The first information generating circuit provides a first information signal. In a first state, the first information generating circuit is coupled to a first multi-function pin through the first switching circuit, and provides the first information signal to the control integrated circuit. In a second state, the monitoring circuit controls the first switching circuit through the first switching signal, so that the monitoring circuit is coupled to the first multi-function pin through the first switching circuit, so as to provide at least one monitoring signal to the control integrated circuit.

Description

Power integrated circuit, control integrated circuit and circuit monitoring method

The present invention relates to a power integrated circuit, and in particular to a power integrated circuit, a control integrated circuit, and a circuit monitoring method.

When an abnormal condition (such as overvoltage, overcurrent, or overtemperature) occurs in an existing power conversion system, the output stage with the abnormality connects the corresponding internal ground resistor to the pulse width modulation (PWM) pin, depending on the type of abnormal condition. Different resistor values correspond to different abnormal conditions, and an abnormality notification signal is simultaneously issued to the controller. When the controller receives the abnormality notification signal, it completely stops generating PWM signals and receives the abnormal voltage generated by the internal resistor of the output stage to determine the type of abnormal condition. Alternatively, when an abnormal condition occurs, a voltage source is connected to the output pin of the output stage where the abnormal condition occurs. This voltage provides a detection voltage corresponding to the different abnormal conditions, allowing the controller to decode the detection voltage and determine the abnormal condition occurring in the corresponding phase. However, these methods all use voltage levels to identify abnormal conditions, making the controller's voltage reading susceptible to interference from noise or component errors, resulting in judgment errors. To reduce judgment errors, the judgment voltage level is typically increased, thus limiting the types of abnormal conditions that can be detected by existing power conversion systems.

This invention is directed to a power integrated circuit, a control integrated circuit, and a circuit monitoring method that can increase the types of abnormal conditions that can be detected, thereby enhancing circuit protection capabilities.

According to an embodiment of the present invention, a power supply integrated circuit of the present invention has a first multi-function pin coupled to a control integrated circuit. The power supply integrated circuit includes a monitoring circuit, a first information generation circuit, and a first switching circuit. The monitoring circuit monitors the power supply integrated circuit and provides at least one monitoring signal and a first switching signal. The first information generation circuit provides a first information signal. The first switching circuit is coupled to the first multi-function pin, the monitoring circuit, and the first information generation circuit. In a first state, the first information generation circuit is coupled to the first multi-function pin via the first switching circuit and provides the first information signal to the control integrated circuit. In the second state, the monitoring circuit controls the first switching circuit via the first switching signal, so that the monitoring circuit is coupled to the first multi-function pin via the first switching circuit to provide at least one monitoring signal to the control integrated circuit.

In an embodiment of the present invention, the power integrated circuit further includes a second multi-function pin coupled to the control integrated circuit. The power integrated circuit further includes a preset signal source, a second information generating circuit, and a second switching circuit. The second switching circuit is coupled to the second multi-function pin, the second information generating circuit, and the preset signal source, and switches the second multi-function pin to the second information generating circuit or the preset signal source based on the first switching signal.

In an embodiment of the present invention, the monitoring circuit includes an encoding circuit. The first switching signal enables the encoding circuit.

In an embodiment of the present invention, the monitoring circuit monitors multiple operating information including at least one of the output current, output voltage, or temperature of the power integrated circuit to generate at least one corresponding monitoring signal.

In an embodiment of the present invention, at least one monitoring signal is a digital signal, and is generated using at least one of a coding method with different frequencies, different duty cycles, and different data packets.

In an embodiment of the present invention, the power integrated circuit further includes a first pulse width modulation (PWM) pin coupled to the control integrated circuit. In a first state, the power integrated circuit receives a PWM signal generated by the control integrated circuit via the first PWM pin. In a second state, the control integrated circuit stops outputting the PWM signal.

According to an embodiment of the present invention, a control integrated circuit has a third multi-function pin coupled to a power integrated circuit. The control integrated circuit includes a third switching circuit, a control loop, and a decoding circuit. The third switching circuit is coupled to the third multi-function pin and receives at least one monitoring signal or a first information signal from the power integrated circuit via the third multi-function pin. The control loop is coupled to the third switching circuit and receives the first information signal to perform a first-state circuit operation. The decoding circuit is coupled to the third switching circuit, receives the at least one monitoring signal, and decodes the at least one monitoring signal. The third switching circuit determines whether the third multi-function pin is connected to the control loop or the decoding circuit based on the first information signal or the at least one monitoring signal.

In an embodiment of the present invention, the third switching circuit includes a fourth switching circuit and a determination circuit. The fourth switching circuit is coupled to the third multi-function pin, the control loop, and the decoding circuit. The determination circuit is coupled to the fourth switching circuit and the third multi-function pin and provides a second switch control signal to the fourth switching circuit.

In an embodiment of the present invention, the control integrated circuit further includes a fourth multi-function pin coupled between the third switching circuit and the power integrated circuit. The third switching circuit further includes a fourth switching circuit. The fourth switching circuit is coupled to the third multi-function pin, the fourth multi-function pin, the control loop, and the decoding circuit. The fourth switching circuit receives a second information signal or a preset signal via the fourth multi-function pin.

According to an embodiment of the present invention, a circuit monitoring method is applicable to a power supply integrated circuit. The power supply integrated circuit has a first multi-function pin. The power supply integrated circuit includes a monitoring circuit, a first signal generating circuit, and a first switching circuit. The circuit monitoring method comprises the following steps: in a first state, the first signal generating circuit provides a first information signal to the first multi-function pin via the first switching circuit; and in a second state, the monitoring circuit controls the first switching circuit such that the monitoring circuit is coupled to the first multi-function pin via the first switching circuit to provide at least one monitoring signal to the first multi-function pin.

In an embodiment of the present invention, the power integrated circuit further includes a second multi-function pin. The power integrated circuit further includes a preset signal source, a second information generating circuit, and a second switching circuit. The second switching circuit switches the second multi-function pin to connect to the second information generating circuit or the preset signal source based on the first switching signal.

In an embodiment of the present invention, the monitoring circuit includes a coding circuit, wherein the circuit monitoring method further includes the following step: enabling the coding circuit via a first switching signal.

In an embodiment of the present invention, the step of generating at least one monitoring signal includes the following steps: monitoring a plurality of operating information including at least one of the output current, output voltage, or temperature of the power integrated circuit by a monitoring circuit to generate at least one corresponding monitoring signal.

In an embodiment of the present invention, at least one monitoring signal is a digital signal, and is generated using at least one of a coding method with different frequencies, different duty cycles, and different data packets.

Based on the above, the power integrated circuit, control integrated circuit, and circuit monitoring method of the present invention can effectively monitor the power integrated circuit through multi-functional pins. When an abnormal state occurs in the power integrated circuit, the monitoring circuit provides a corresponding monitoring signal, increasing the types of abnormal state feedback. This allows the control integrated circuit to effectively take corresponding protective measures.

To make the above features and advantages of the present invention more clearly understood, the following examples are given and described in detail with reference to the accompanying drawings.

10, 30: Power conversion system

100, 300, 700_1~700_x: Power Integrated Circuits

101, 201, 301, 302, 401, 402, 601: Multi-function pins

110, 310: First switching circuit

120, 320: First information generation circuit

130, 330: Monitoring circuit

200, 400, 600, 800: Control integrated circuit

331: Encoding circuit

332:Logic Circuit

332_1, 332_2: Comparator

332_3: Or gate

Vth1: First threshold voltage

Vth2: Second threshold voltage

PT1, PT2: Notification signals

340: Second switching circuit

350: Second information generation circuit

360:Default signal source

410, 610: Third switching circuit

411, 611: Fourth switching circuit

420, 620: Control loop

430, 630: Decoding circuit

612: Judgment Circuit

VP: Default signal

V_SP1, V_SP2: Monitoring signals

S1: First switching signal

S2: Second switching signal

SP: Monitoring signal

S_IMON: First Information Signal

S_TMON: Second information signal

V_IMON, V_TMON: voltage

IMON, IMON1, IMON2, IMONx, TMON, TMON1, TMON2, TMONx, VREF, PWM, PWM1, PWM2, PWM_x: pins

S210, S220: Steps

t1, t2, t3, t4: time

Figure 1 is a schematic circuit diagram of a power conversion system according to an embodiment of the present invention.

Figure 2 is a flow chart of a circuit monitoring method according to an embodiment of the present invention.

Figure 3 is a circuit diagram of a power conversion system according to another embodiment of the present invention.

Figure 4 is a schematic diagram of the logic circuit in a monitoring circuit according to an embodiment of the present invention.

Figure 5A is a schematic diagram of signal changes in an embodiment of the present invention.

Figure 5B is a schematic diagram of signal changes in another embodiment of the present invention.

Figure 6 is a circuit diagram of a control integrated circuit according to another embodiment of the present invention.

Figure 7 is a circuit diagram of a power conversion system according to another embodiment of the present invention.

Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

FIG1 is a schematic circuit diagram of a power conversion system according to an embodiment of the present invention. Referring to FIG1 , the power conversion system 10 includes a power supply integrated circuit 100 and a control integrated circuit 200. The power supply integrated circuit 100 has a multi-function pin 101 (a first multi-function pin). The control integrated circuit 200 has a multi-function pin 201 (a third multi-function pin). The power supply integrated circuit 100 is coupled to the multi-function pin 201 of the control integrated circuit 200 via the multi-function pin 201. In this embodiment, the power supply integrated circuit 100 can be a smart power stage (SPS). The control integrated circuit 200 can be a pulse width modulation (PWM) controller. The control integrated circuit 200 controls the power integrated circuit 100 to output power. In this embodiment, the power integrated circuit 100 includes a first switching circuit 110, a first information generation circuit 120, and a monitoring circuit 130. The first switching circuit 110 is coupled to the first information generation circuit 120, the monitoring circuit 130, and the multi-function pin 101. In this embodiment, the monitoring circuit 130 monitors various operating information of the power integrated circuit 100, including but not limited to at least one of the output current, output voltage, or temperature of the power integrated circuit 100, to generate at least one corresponding monitoring signal SP and a first switching signal S1 to the first switching circuit 110.

FIG2 is a flow chart of a circuit monitoring method according to an embodiment of the present invention. Referring to FIG1 and FIG2 , the power conversion system 10 may execute the following steps S210-S220. In step S210, in a first state (normal state), the power integrated circuit 100 may provide a first information signal S_IMON to the multi-function pin 101 via the first information generating circuit 120 through the first switching circuit 110, and then to the control integrated circuit 200. In this embodiment, the first information generating circuit 120 may be a current monitoring circuit, and the first information signal S_IMON may be a current monitoring signal. The multi-function pin 101 may be a current information feedback pin (pin IMON). The multi-function pin 201 can be a current monitoring information pin. Furthermore, the first information generation circuit 120 can be used to monitor the output current of the power integrated circuit 100 and return a first information signal S_IMON related to the output current to the control integrated circuit 200, so that the control integrated circuit 200 can control the output of the power integrated circuit 100 based on the first information signal S_IMON.

In another embodiment, step S210, the first signal generating circuit 120 can also be used to generate power information. Specifically, in the first state (normal state), the control integrated circuit 200 provides a control signal to the first signal generating circuit 120 via the multi-function pin 101 and the first switching circuit 110, thereby outputting electrical energy (power). In this alternative embodiment, the first signal generating circuit 120 can be an output stage circuit, and the control signal is a pulse width modulation (PWM) signal. The multi-function pin 101 is the PWM input pin, and the multi-function pin 201 is the PWM signal output pin. Furthermore, the first signal generating circuit 120 can be used to generate an output voltage.

In step S220, in the second state (abnormal state), the monitoring circuit 130 controls the first switching circuit 110 via the first switching signal S1, so that the monitoring circuit 130 is coupled to the first multi-function pin 101 via the first switching circuit 110 to provide at least one monitoring signal SP to the multi-function pin 101, which is then provided to the control integrated circuit 200. In this embodiment, the monitoring circuit 130 can monitor whether the power integrated circuit 100 has at least one of overcurrent (OC), overvoltage (OV), and overtemperature (OT) and generate a corresponding monitoring signal SP. These monitoring signals SP notify the power integrated circuit 100 to perform corresponding circuit protection control.

Figure 3 is a schematic circuit diagram of a power conversion system according to another embodiment of the present invention. Referring to Figure 3 , the power conversion system 30 includes a power integrated circuit 300 and a control integrated circuit 400. The power integrated circuit 300 has a multi-function pin 301 (a first multi-function pin) and a multi-function pin 302 (a second multi-function pin). The control integrated circuit 400 has a multi-function pin 401 (a third multi-function pin) and a multi-function pin 402 (a fourth multi-function pin). The power integrated circuit 300 is coupled to the multi-function pin 401 of the control integrated circuit 400 via the multi-function pin 301. The power integrated circuit 300 is coupled to the multi-function pin 402 of the control integrated circuit 400 via the multi-function pin 302.

In this embodiment, the power supply integrated circuit 300 includes a first switching circuit 310, a first information generating circuit 320, a monitoring circuit 330, a second switching circuit 340, a second information generating circuit 350, and a default signal source 360. The first switching circuit 310 is coupled to the first information generating circuit 320, the monitoring circuit 130, and the multi-function pin 301. The second switching circuit 340 is coupled to the multi-function pin 302, the second information generating circuit 350, and the default signal source 360. In this embodiment, the monitoring circuit 330 monitors the operating status of the power supply integrated circuit 300 and provides at least one monitoring signal SP and a first switching signal S1 to the first switching circuit 310 and the second switching circuit 340. In this embodiment, the first switching circuit 310 can switch the multi-function pin 301 to connect to the first information generating circuit 320 or the monitoring circuit 330 according to the first switching signal S1. The second switching circuit 340 can switch the multi-function pin 302 to connect to the second information generating circuit 350 or the default signal source 360 according to the first switching signal S1.

In this embodiment, the monitoring circuit 330 includes an encoding circuit 331. The encoding circuit 331 includes an enable pin EN and an output pin OUT. The enable pin EN receives a first switching signal S1. The monitoring circuit 330 can use the first switching signal S1 to enable the encoding circuit 331, causing the encoding circuit 331 to output at least one monitoring signal SP to the first switching circuit 310, thereby reducing power consumption during monitoring circuit operation. In this embodiment, the at least one monitoring signal SP can be a digital signal, and the encoding circuit 331 can generate the encoded signal of the at least one monitoring signal SP using at least one encoding method selected from among different frequencies, different duty cycles, and different data packets. In this way, the monitoring signal SP can carry more diverse information and provide it to the control integrated circuit 400, including but not limited to the degree of overcurrent/overvoltage and the real-time temperature of the power integrated circuit 300.

In this embodiment, the control integrated circuit 400 includes a third switching circuit 410, a control loop 420, and a decoding circuit 430. The third switching circuit 410 is coupled to the multi-function pin 401 and receives at least one monitoring signal SP or a first information signal S_IMON from the power integrated circuit 300 via the third multi-function pin 401. In this embodiment, the third switching circuit 410 includes a fourth switching circuit 411. The fourth switching circuit 411 is coupled to the multi-function pin 401, the multi-function pin 402, the control loop 420, and the decoding circuit 430. The fourth switching circuit 411 receives the second information signal S_TMON or a preset signal VP (e.g., a fixed voltage of 3.3 volts, a ground voltage, or a voltage/current waveform with a specific cycle) via the multi-function pin 402. In this embodiment, when the fourth switching circuit 411 receives the second information signal S_TMON from the power integrated circuit 300 via the multi-function pin 402, the fourth switching circuit 411 is switched to connect to the control loop 420. When the fourth switching circuit 411 receives the preset signal VP from the power integrated circuit 300 via the multi-function pin 402, the fourth switching circuit 411 is switched to connect to the decoding circuit 430. The default signal VP serves as an error indication signal to report to the control integrated circuit 400 that the operation of the power integrated circuit 300 has entered the second state (abnormal state).

In this embodiment, the control loop 420 is coupled to the third switching circuit 410. When the control loop 420 receives the first information signal S_IMON through the third switching circuit 410, the control loop 420 can perform normal circuit operations. The decoding circuit 430 is coupled to the third switching circuit 410. When the decoding circuit 430 receives at least one monitoring signal SP through the third switching circuit 410, the decoding circuit 430 can decode the at least one monitoring signal SP. In this embodiment, the third switching circuit 410 can determine whether the third multi-function pin 401 is connected to the control loop 420 or the decoding circuit 430 based on the first information signal S_IMON or the at least one monitoring signal SP.

In this embodiment, multi-function pins 301 and 401 may be, for example, a current information feedback pin (pin IMON) and a current monitoring information pin (pin V_IMON), respectively. Multi-function pin 302 may be, for example, a temperature information feedback pin (pin TMON). Multi-function pin 402 may be, for example, a temperature monitoring information pin (pin V_TMON). In this embodiment, first signal generating circuit 320 may be a current monitoring circuit, and first signal signal S_IMON may be a current monitoring signal. The first information generation circuit 320 can be used to monitor the output current of the power supply integrated circuit 300 and return a current monitoring signal related to the output current to the control integrated circuit 400, so that the control integrated circuit 400 can control the output of the power supply integrated circuit 300 based on the current monitoring signal. In this embodiment, the second information generation circuit 350 can be a temperature monitoring circuit, and the second information signal S_TMON can be a temperature monitoring signal. The second information generation circuit 350 can be used to monitor the temperature of the power supply integrated circuit 300 and return the second information signal S_TMON to the control integrated circuit 400. Therefore, the control integrated circuit 400 can control the output of the power integrated circuit 300 according to the first information signal S_IMON and the second information signal S_TMON.

Figure 4 is a schematic diagram of the logic circuit of a monitoring circuit according to an embodiment of the present invention. Referring to Figures 3 and 4, monitoring circuit 330 may further include logic circuit 332 of Figure 4. In this embodiment, the output of logic circuit 332 may be coupled to encoding circuit 331 to provide notification signals PT1 and PT2 to encoding circuit 331 and also generate a first switching signal S1. Based on notification signals PT1 and PT2, encoding circuit 331 may generate a corresponding monitoring signal SP using a lookup table or other known encoding methods. In this embodiment, logic circuit 332 includes comparators 332_1, 332_2, and an OR gate 332_3. Comparator 332_1 compares the first information signal S_IMON with the first threshold voltage Vth1 and outputs a notification signal PT1. Comparator 332_2 compares the second information signal S_TMON with the second threshold voltage Vth2 and outputs a notification signal PT2. OR gate 332_3 receives notification signals PT1 and PT2. Once either notification signal PT1 or notification signal PT2 is high, OR gate 332_3 generates a first switching signal S1 to control the connection state of first switching circuit 110.

Figure 5A is a schematic diagram of signal changes in one embodiment of the present invention. Referring to Figures 3, 4, and 5A, an overcurrent event occurs in power integrated circuit 300. Before time t1 (i.e., the aforementioned first state or normal state), multi-function pins 301 and 401 transmit a first information signal S_IMON (current monitoring signal), causing the voltage V_IMON on multi-function pins 301 and 401 to vary in accordance with the first information signal S_IMON. Multi-function pins 302 and 402 transmit a second information signal S_TMON (temperature monitoring signal), causing the voltage V_TMON on multi-function pins 302 and 402 to vary in accordance with the second information signal S_TMON. The notification signals PT1 and PT2 are at a low voltage level, so the first switching signal S1 is at a low voltage level.

At time t1, an overcurrent event (i.e., the aforementioned second state or abnormal state) occurs in the power integrated circuit 300. The voltage V_IMON on the multi-function pins 301 and 401 exceeds the first threshold voltage Vth1. The notification signal PT1 output by the comparator 332_1 switches to a high voltage level, indicating an overcurrent. Consequently, the first switching signal S1 output by the OR gate 332_3 switches to a high voltage level. As a result, the first switching circuit 310 is switched, coupling the output of the monitoring circuit 330 to the multi-function pin 301 via the first switching circuit 310. The second switching circuit 340 is switched, coupling the output of the default signal source 360 to the multi-function pin 302 via the second switching circuit 340. The default signal source 360 provides a 3.3V voltage to the fourth switching circuit 411 of the control integrated circuit 400 to switch the fourth switching circuit 411. The fourth switching circuit 411 is switched to couple the multi-function pin 401 to the decoding circuit 430.

Between time t1 and time t2, the encoding circuit 331 generates a corresponding monitoring signal V_SP1 based on the notification signal PT1 and provides the monitoring signal V_SP1 to the decoding circuit 430 via the first switching circuit 310, the multi-function pin 301, the multi-function pin 401, and the fourth switching circuit 411. The monitoring signal V_SP1 is a digitally encoded signal and may have a specific operating frequency (e.g., 400 Hz) to indicate an overcurrent condition. In this way, the decoding circuit 430 of the control integrated circuit 400 can decode the monitoring signal V_SP1 to obtain overcurrent status information of the power integrated circuit 300 and perform corresponding circuit protection control operations, such as stopping the output of the pulse width modulation signal or reducing the on-time of the pulse width modulation signal output to the power integrated circuit 300.

After time t2, if the voltage V_IMON on the multi-function pins 301 and 401 no longer exceeds the first threshold voltage Vth1, the notification signal PT1 output by the comparator 332_1 returns to a low voltage level. Consequently, the first switching signal S1 output by the OR gate 332_3 also returns to a low voltage level. Consequently, the first switching circuit 310 is switched so that the output of the first information generation circuit 320 is re-coupled to the multi-function pin 301 via the first switching circuit 310, providing the first information signal S_IMON to the control integrated circuit 400. The second switching circuit 340 is switched so that the output of the second information generation circuit 350 is coupled to the multi-function pin 302 via the second switching circuit 340. The fourth switching circuit 411 returns the multi-function pin 401 to the control loop 420 according to the second information signal S_TMON.

FIG5B is a schematic diagram of signal changes according to another embodiment of the present invention. Referring to FIG3 , FIG4 , and FIG5B , an over-temperature event occurs in power supply integrated circuit 300 as an example. Before time t3 (i.e., the aforementioned first state or normal state), multi-function pins 301 and 401 transmit a first information signal S_IMON (current monitoring signal). Therefore, the voltage V_IMON on multi-function pins 301 and 401 varies in accordance with the first information signal S_IMON. Multi-function pins 302 and 402 transmit a second information signal S_TMON (temperature monitoring signal). Therefore, the voltage V_TMON on multi-function pins 302 and 402 varies in accordance with the second information signal S_TMON. The notification signals PT1 and PT2 are at a low voltage level, so the first switching signal S1 is at a low voltage level.

At time t3, an overtemperature event (i.e., the aforementioned second state or abnormal state) occurs in the power integrated circuit 300. The voltage V_TMON on the multi-function pins 302 and 402 exceeds the second threshold voltage Vth2, causing the notification signal PT2 output by the comparator 332_2 to switch to a high voltage level. Consequently, the first switching signal S1 output by the OR gate 332_3 switches to a high voltage level. Consequently, the first switching circuit 310 is switched, coupling the output of the monitoring circuit 330 to the multi-function pin 301 via the first switching circuit 310. The second switching circuit 340 is switched, coupling the output of the default signal source 360 to the multi-function pin 302 via the second switching circuit 340. The default signal source 360 provides a 3.3V voltage to the fourth switching circuit 411 of the control integrated circuit 400 to switch the fourth switching circuit 411. The fourth switching circuit 411 is switched to couple the multi-function pin 401 to the decoding circuit 430.

Between time t3 and time t4, encoding circuit 331 generates monitoring signal V_SP2 based on notification signal PT2 and provides monitoring signal V_SP2 to decoding circuit 430 via first switching circuit 310, multi-function pin 301, multi-function pin 401, and fourth switching circuit 411. Monitoring signal V_SP2 is a digitally encoded signal and may have a specific operating frequency (e.g., 200 Hz) to indicate an overtemperature condition. It should be noted that monitoring signal V_SP2 in FIG. 5B has a different operating frequency than monitoring signal V_SP1 in FIG. 5A . In this way, the decoding circuit 430 of the control integrated circuit 400 can decode the monitoring signal V_SP2 to obtain over-temperature status information of the power integrated circuit 300 and perform corresponding circuit protection control operations, such as stopping the output of the pulse width modulation signal or reducing the on-time of the pulse width modulation signal output to the power integrated circuit 300.

After time t4, if the voltage V_TMON on the multi-function pin 301 and the multi-function pin 402 no longer exceeds the second threshold voltage Vth2, the notification signal PT2 output by the comparator 332_2 returns to a low voltage level. Consequently, the first switching signal S1 output by the OR gate 332_3 also returns to a low voltage level. Consequently, the first switching circuit 310 is switched, causing the output of the first information generation circuit 320 to be re-coupled to the multi-function pin 301 via the first switching circuit 310. The second switching circuit 340 is switched, causing the second information generation circuit 350 to be coupled to the multi-function pin 302 via the second switching circuit 340. The fourth switching circuit 411 reconnects the multi-function pin 401 to the control loop 420 based on the second information signal S_TMON. Therefore, the power conversion system 30 of this embodiment can transmit a variety of status information through a single pin, achieving a complete and effective circuit monitoring function.

Figure 6 is a schematic circuit diagram of a control integrated circuit according to another embodiment of the present invention. Referring to Figure 6 , the control integrated circuit of the present invention can be implemented using the circuit shown in Figure 6 . In this embodiment, the control integrated circuit 600 has a multi-function pin 601 (a third multi-function pin). The power integrated circuit is coupled to the multi-function pin 601 of the control integrated circuit 600 via a multi-function pin (e.g., multi-function pin 101 of the power integrated circuit 100 in Figure 1 ). The control integrated circuit 600 includes a third switching circuit 610, a control loop 620, and a decoding circuit 630. The third switching circuit 610 is coupled to the multi-function pin 601 and receives at least one monitoring signal SP or a first information signal S_IMON from the power integrated circuit via the multi-function pin 601. In this embodiment, the third switching circuit 610 includes a fourth switching circuit 611 and a determination circuit 612. The fourth switching circuit 611 is coupled to the multi-function pin 601, a control loop 620, and a decoding circuit 630. The determination circuit 612 is coupled to the fourth switching circuit 611 and the multi-function pin 601 and provides a second switch control signal S2 to the fourth switching circuit 611.

In this embodiment, when determination circuit 612 determines that multi-function pin 601 receives first information signal S_IMON from the power integrated circuit, determination circuit 612 controls fourth switching circuit 611 via second switch control signal S2 to connect multi-function pin 601 to control loop 620. Control loop 620 generates a pulse width modulation signal based on first information signal S_IMON to control the power integrated circuit for normal output. In this embodiment, when the signal received by determination circuit 612 exceeds the first threshold voltage Vth1, it determines that the signal received by multi-function pin 601 from the power integrated circuit is at least one monitoring signal SP. At this point, determination circuit 612 controls fourth switching circuit 611 via second switch control signal S2 to connect and latch multi-function pin 601 to decoding circuit 630. Decoding circuit 630 decodes the at least one monitoring signal SP to obtain circuit abnormality status information of the power integrated circuit and latches this abnormality to perform corresponding circuit protection control operations.

Figure 7 is a schematic circuit diagram of a power conversion system according to another embodiment of the present invention. Referring to Figure 7 , the power conversion system of this embodiment may include multiple power integrated circuits 700_1 through 700_x and a control integrated circuit 800, where x is a positive integer. Control integrated circuit 800 is coupled to pins IMON1 through IMONx, TMON1 through TMONx, PWM, PWM1 through PWM_x, and VREF of power integrated circuits 700_1 through 700_x via pins IMON, TMON, PWM, and VREF. The power integrated circuits 700_1 to 700_x can be implemented, for example, by the power integrated circuit 300 of the embodiment shown in FIG. 3 , and the control integrated circuit 800 can be implemented, for example, by the control integrated circuit 400 of the embodiment shown in FIG. 3 , but the present invention is not limited thereto.

In this embodiment, the control integrated circuit 800 can determine whether to output a pulse-width modulated signal to the corresponding power integrated circuit based on a first information signal or a monitoring signal provided by the corresponding power integrated circuit. When a power integrated circuit is operating in a first state (normal state), the power integrated circuit can receive the pulse-width modulated signal generated by the control integrated circuit 800 via the pulse-width modulation pin PWM. When a power integrated circuit operates in the second state (abnormal state), the control integrated circuit 800 can stop outputting the pulse width modulation signal to this power integrated circuit without affecting other power integrated circuits operating in the first state (normal state).

In summary, the power supply integrated circuit, control integrated circuit, and circuit monitoring method of the present invention can transmit power supply integrated circuit status information and a wider range of abnormal status notifications via multi-function pins. Furthermore, the control integrated circuit can effectively control and protect the power supply integrated circuit based on the power supply integrated circuit status information and abnormal status notifications.

Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, persons skilled in the art should understand that they may modify the technical solutions described in the above embodiments or substitute equivalent features for some or all of the technical features therein. Such modifications or substitutions do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

10: Power Conversion System 100: Power Integrated Circuit 101, 201: Multi-function Pins 110: First Switching Circuit 120: First Information Generating Circuit 130: Monitoring Circuit 200: Control Integrated Circuit S1: First Switching Signal SP: Monitoring Signal S_IMON: First Information Signal

Claims (14)

A power supply integrated circuit (IC) has a first multi-function pin coupled to a control IC, wherein the IC includes: a monitoring circuit that monitors the power supply IC and provides at least one monitoring signal and a first switching signal; a first information generation circuit that provides a first information signal; and a first switching circuit coupled to the first multi-function pin, the monitoring circuit, and the first information generation circuit. In a first state, the first information generation circuit is coupled to the first multi-function pin via the first switching circuit and provides the first information signal to the control IC. In a second state, the monitoring circuit controls the first switching circuit via the first switching signal, such that the monitoring circuit is coupled to the first multi-function pin via the first switching circuit to provide the at least one monitoring signal to the control integrated circuit. The power integrated circuit of claim 1 further comprises a second multi-function pin coupled to the control integrated circuit, wherein the power integrated circuit further includes: a default signal source; a second information generating circuit; and a second switching circuit coupled to the second multi-function pin, the second information generating circuit, and the default signal source, and configured to switch the second multi-function pin to the second information generating circuit or the default signal source in response to the first switching signal. The power integrated circuit of claim 1, wherein the monitoring circuit comprises: A coding circuit, wherein the first switching signal enables the coding circuit. The power integrated circuit of claim 1, wherein the monitoring circuit monitors a plurality of operating information including at least one of an output current, an output voltage, or a temperature of the power integrated circuit to generate the corresponding at least one monitoring signal. The power integrated circuit of claim 1, wherein the at least one monitoring signal is a digital signal, and is generated by encoding at least one of different frequencies, different duty cycles, and different data packets. As described in claim 1, the power integrated circuit also has a first pulse width modulation pin coupled to the control integrated circuit, wherein in the first state, the power integrated circuit receives the pulse width modulation signal generated by the control integrated circuit through the first pulse width modulation pin, and in the second state, the control integrated circuit stops outputting the pulse width modulation signal. A control integrated circuit has a third multi-function pin coupled to a power integrated circuit, wherein the control integrated circuit includes: a third switching circuit coupled to the third multi-function pin and receiving at least one monitoring signal or a first information signal provided by the power integrated circuit via the third multi-function pin; a control loop coupled to the third switching circuit and receiving the first information signal to perform a circuit operation in a first state; and a decoding circuit coupled to the third switching circuit and receiving and decoding the at least one monitoring signal. The third switching circuit determines whether the third multi-function pin is connected to the control loop or the decoding circuit based on the first information signal or the at least one monitoring signal. The control integrated circuit of claim 7, wherein the third switching circuit comprises: a fourth switching circuit coupled to the third multi-function pin, the control loop, and the decoding circuit; and a determination circuit coupled to the fourth switching circuit and the third multi-function pin and providing a second switch control signal to the fourth switching circuit. The control integrated circuit of claim 7 further comprises a fourth multi-function pin coupled between the third switching circuit and the power integrated circuit, wherein the third switching circuit further comprises: a fourth switching circuit coupled to the third multi-function pin, the fourth multi-function pin, the control loop, and the decoding circuit, wherein the fourth switching circuit receives a second information signal or a preset signal via the fourth multi-function pin. A circuit monitoring method is provided for a power supply integrated circuit (IC), wherein the IC has a first multi-function pin and includes a monitoring circuit, a first signal generating circuit, and a first switching circuit. The method comprises: In a first state, a first signal generating circuit provides a first signal to the first multi-function pin via the first switching circuit; and In a second state, the monitoring circuit controls the first switching circuit such that the monitoring circuit is coupled to the first multi-function pin via the first switching circuit to provide at least one monitoring signal to the first multi-function pin. The circuit monitoring method of claim 10, wherein the power integrated circuit further comprises a second multi-function pin, a preset signal source, a second information generating circuit, and a second switching circuit, wherein the second switching circuit switches the second multi-function pin to connect to the second information generating circuit or the preset signal source in response to a first switching signal. The circuit monitoring method of claim 10, wherein the monitoring circuit includes an encoding circuit, and wherein the circuit monitoring method further comprises: enabling the encoding circuit via a first switching signal. The circuit monitoring method of claim 10, wherein the step of generating the at least one monitoring signal comprises: Monitoring a plurality of operating information including at least one of an output current, an output voltage, or a temperature of the power integrated circuit via the monitoring circuit to generate the corresponding at least one monitoring signal. The circuit monitoring method of claim 10, wherein the at least one monitoring signal is a digital signal, and the coded signal of the at least one monitoring signal is generated using a coding method of at least one of different frequencies, different duty cycles, and different data packets.