[0022] See figure 1 In a first preferred embodiment of the present invention, a power detection circuit is used to detect the power consumption of an electronic device, which includes a power meter 20, an MCU (Micro Control Unit, micro control unit) 30, A memory 40 connected to the MCU 30, a main functional load 50, a current detection module 60, a power supply module 80, and a calibration circuit 90 connected to the MCU 30. The power supply module 80 is connected to an AC (alternating current, alternating current) power supply 10, and can convert the AC voltage output by the AC power supply 10 into a DC voltage and provide it to each load in the circuit. The power module 80 includes a bridge rectifier circuit, a PFC (Power Factor Correction, power factor correction) module, and an AC-to-DC (AC to DC) conversion module. The memory 40 is used to store the data received by the MCU 30, and is convenient to call and query historical data. In one embodiment, all components such as the power module 80, the MCU 30, and the main functional load 50 can be installed in the electronic device, or some components can be plugged into the electronic device in an external form.
[0023] The power meter 20 is connected to the AC power supply 10 for detecting the input power of the AC power supply 10 to the power supply module 80 and outputting the measured power value to the MCU 30.
[0024] The current detection module 60 is connected to the power module 80 through a diode D1 for detecting the output current of the power module 80 and outputting the detected current signal to the MCU 30. The output voltage of the power module 80 has a preset voltage value, the MCU 30 stores the preset voltage value, and the MCU 30 is based on the current signal detected by the current detection module 60 and The preset voltage value is used to calculate the output power of the power module 80 or the power consumption of the load connected to the power module 80. The MCU 30 can also calculate the conversion efficiency of the power module 80 according to the input power and output power of the power module 80. The MCU 30 can also compare the measured conversion efficiency of the power module 80 with the factory conversion efficiency of the power module 80 to obtain the degree of aging of the power module 80.
[0025] The main functional load 50 includes a display module (such as a display screen), a circuit board, and other components. The MCU 30 is connected to the display module, and the display module can display the input power of the power supply module 80 , Output power and conversion efficiency and other parameters.
[0026] The correction circuit 90 includes a first triode Q1, the base of the first triode Q1 is connected to the MCU 30 through a first resistor R1, and the collector of the first triode Q1 passes A second resistor R2 is connected to the current detection module 60, and the emitter of the first transistor Q1 is grounded. In one embodiment, the first transistor Q1 is an NPN type transistor.
[0027] The power detection circuit also includes a second transistor Q2 and a third transistor Q3. The emitter of the second transistor Q2 is connected to the current detecting module 60, and one end of a third resistor R3 is connected to the emitter of the current detecting module 60 and the second transistor Q2 Connected, the other end of the third resistor R3 is connected to the base of the second transistor Q2 through a fourth resistor R4. The collector of the second transistor Q2 is connected to the main functional load 50. One end of a fifth resistor R5 is connected to the base of the second triode Q2 through the fourth resistor R4, and the other end is connected to the collector of the third triode Q3. The base of the third transistor Q3 is connected to the MCU 30, and the emitter is grounded. In one embodiment, the second triode Q2 is a PNP type triode, and the third triode Q3 is an NPN type triode.
[0028] The MCU 30 is also connected with a plurality of key switches K1 to K4. The key switch K1 is used to activate the correction circuit 90, the key switch K2 is used to enable the manual power correction function, the key switch K3 is used to manually calibrate and increase the power of the electronic device, and the key switch K4 is used to manually The correction reduces the power of the electronic device.
[0029] When the key switch K1 is pressed to activate the correction circuit 90, the MCU 30 outputs a high-level signal to the first transistor Q1 and a low-level signal to the third triode. Tube Q3, the first transistor Q1 is turned on, and both the second transistor Q2 and the third transistor Q3 are turned off. The main functional load 50 is powered off, the second resistor R2 is powered on, the current detection module 60 detects the current flowing through the second resistor R2 and outputs the detected current signal to the MCU 30, The MCU 30 can calculate the output power of the power module 80 when the second resistor R2 is externally connected.
[0030] When the main functional load 50 is powered on, the correction circuit 90 is turned off, the MCU 30 outputs a low-level signal to the first transistor Q1, and outputs a high-level signal to the third transistor Q1. The transistor Q3, the first transistor Q1 is turned off, and the second transistor Q2 and the third transistor Q3 are both turned on. The current detection module 60 detects the current flowing to the main functional load 50 and outputs the detected current signal to the MCU 30. The MCU 30 can calculate that the power module 80 is supplying the main The output power when the functional load 50 is powered.
[0031] In the above embodiment, the first triode Q1 and the second triode Q2 cannot be turned on at the same time, and one of the first triode Q1 and the second triode Q2 must be off. Open or both or disconnect at the same time.
[0032] See figure 2 In a second preferred embodiment of the present invention, a power detection circuit is provided with a voltage detection module 70 compared to the power detection circuit of the first embodiment described above, and the voltage detection module 70 is connected Between the diode D1 and the current detection module 60, the voltage detection module 70 detects the voltage output by the power module 80 to the load, and sends the detected voltage signal to the The MCU 30 can avoid errors caused by the difference between the actual output voltage of the power module 80 and the preset output voltage.
[0033] See image 3 In a third embodiment of the present invention, compared to the power detection circuit of the first embodiment described above, a power detection circuit eliminates the need for a power meter connected to the AC power source 10, and adds a power meter connected to the AC power source 10 A transformer 110 connected to the transformer 110, a detection module 120 connected to the transformer 110, and an operational amplifier 130 connected to the detection module 120. The transformer 110 converts the output voltage of the AC power source 10 and outputs it to the detection module 120. The diode and capacitor in the detection module 120 rectify and filter the signal output by the transformer 110 and then output it to The operational amplifier 130, the operational amplifier 130 amplifies the signal output by the detection module 120 according to a preset ratio and then outputs it to the MCU 30, and the MCU 30 outputs the signal according to the operational amplifier 130 The detection signal of is derived from the output current or output voltage of the AC power supply 10.
[0034] See Figure 4 In a fourth embodiment of the present invention, a power detection circuit is additionally provided with a voltage detection module 70 compared to the power detection circuit of the third embodiment, and the voltage detection module 70 is connected to the Between the diode D1 and the current detection module 60, the voltage detection module 70 detects the voltage output by the power module 80 to the load, and sends the detected voltage signal to the MCU 30, The error caused by the difference between the actual output voltage of the power module 80 and the preset output voltage can be avoided.
[0035] In the above embodiment, the MCU 30 can also be connected with a plurality of correction circuits similar to the correction circuit 90, and each correction circuit includes a triode connected to the MCU 30 and a correction resistor connected to the triode. The correction resistor can be used to correct the detected current signal. These correction circuits can simulate the operation of the circuit under full load (all the resistance of the correction circuit are energized), light load (a small amount of the resistance of the correction circuit is energized), and zero load (all the resistance of the correction circuit are powered off), etc. Power consumption. The MCU 30 can establish a corresponding relationship table between load and power consumption or generate a curve of load and power consumption according to the size of the load and power consumption, and can also generate the conversion efficiency curve of the power module 80 when different loads are externally connected. Using the above-mentioned parameter correspondence table or curve, when the MCU 30 obtains the input power information of the power module 80, it can calculate the output power of the power module 80 according to the conversion efficiency; when the output power of the power module 80 is obtained, The input power of the power module 80 can be calculated according to the conversion efficiency. In the above manner, when the power detection circuit detects the power consumption of the load, it does not need to detect all the parameters (such as input/output power, input/output voltage, output/output current, etc.), and only needs to detect For some parameters (such as output current), the output power, input power and other parameters of the power supply module 80 can be calculated.
[0036] Those of ordinary skill in the art should realize that the above embodiments are only used to illustrate the present invention, but not to limit the present invention. As long as they are within the essential spirit of the present invention, the above embodiments are appropriately made. Changes and changes fall within the scope of protection of the present invention.
