CN101930026B - An electronic device with power loss detection function - Google Patents

Abstract

An electronic device with a power loss detection function belongs to the field of electronics. The voltage and the current are detected between a rectifier of the power supply and the DC-DC converter, the detected voltage and the detected current are multiplied to obtain detected power corresponding to the energy consumed by the load, and then the corresponding power loss, namely the power extracted by the load, is found out from the lookup table according to the detected power and is displayed. Therefore, the electronic device with the power loss detection function of the invention does not need to use an additional power measuring instrument, and a user can obtain the current power loss of the electronic device under the condition of limited cost.

Description

An electronic device with power loss detection function

technical field

The invention relates to the field of electronics, in particular to an electronic device with a power loss detection function.

Background technique

The purpose of the power supply is to provide the load with a stable power supply and to cope with the variable transient change response, and the amount of energy consumed by the load will be determined by the load. For example, when the power supply provides a stable output voltage with a voltage value of V, the load can be regarded as a variable resistance R because the load will change continuously, so the power supply provides the power of the load is V ² /R. Under the allowable output energy range of the power supply, no matter how the load changes, the power supply can provide a stable and constant output voltage to the load. In addition to providing power, existing power supplies usually provide additional functions of over-current protection or over-voltage protection. These two functions are mainly used to protect the power supply and the load when the load is short-circuited or open-circuited. However, the existing power supply does not provide detection of input power.

The usual practice of manufacturers is to use precision power measuring instruments to detect the power fed into the input terminal of the power supply after the power supply is installed in the electronic device. These precision power measuring instruments are expensive and bulky, and are not suitable for installation. Set to generally low-cost consumer electronic devices for sale. Moreover, the manufacturer can only indicate the maximum value and/or the minimum value of the power loss on the label of the electronic device after using a precision power measuring instrument to detect the power loss of the electronic device to verify whether the electronic device conforms to the design. The user cannot know the current power consumption of the electronic device without using an additional power measuring instrument for detection.

Contents of the invention

In view of this, in order to enable the user to obtain the current power loss of the electronic device without using additional power measuring instruments under the condition of limited cost, the present invention proposes an electronic device with a power loss detection function , the technical scheme is as follows:

An electronic device with a power loss detection function, the electronic device includes: a rectifier, a voltage detector, a current detector, a DC-to-DC converter, an analog multiplier, an analog-to-digital converter, and a microcontroller; wherein,

The rectifier is used to convert the received AC power into DC power;

The voltage detector, coupled to the rectifier, is used to detect the voltage of the direct current and output a corresponding detection voltage;

The current detector, coupled to the rectifier, is used to detect the current of the direct current and output a corresponding detection current;

The DC-to-DC converter is coupled to the rectifier through the current detector, and is used to convert the voltage of the DC power into an output voltage and supply power to a load;

The analog multiplier, coupled to the voltage detector and the current detector, is used to multiply the detection voltage and the detection current, and output detection power;

The analog-to-digital converter, coupled to the analog multiplier, is used to convert the detected power from an analog form to a digital form;

The microcontroller, coupled to the analog-to-digital converter, is used to find out the corresponding power loss from a lookup table according to the detected power in digital form, and display it.

The voltage detector includes: two first resistors connected in series; wherein,

One end of the two series-connected first resistors is coupled to the rectifier to receive the direct current, and the other end is grounded, and a common node of the two series-connected first resistors outputs the detection voltage.

The voltage detector includes: two capacitors connected in series; wherein,

One end of the two series-connected capacitors is coupled to the rectifier to receive the direct current, and the other end is grounded, and a common node of the two series-connected capacitors outputs the detection voltage.

The current detector includes: a detection resistor, two second resistors connected in series, two third resistors connected in series, and a differential pressure amplifier; wherein,

The detection resistor has a first end and a second end, the first end is coupled to the rectifier to receive the direct current, and the second end is coupled to the direct current to direct current converter;

One end of the two series-connected second resistors is coupled to the first end of the detection resistor, and the other end is grounded;

One end of the two third resistors connected in series is coupled to the second end of the detection resistor, and the other end is grounded;

The differential pressure amplifier is used to make a difference between the voltage value output by the common joint of the two series-connected second resistors and the voltage output by the common joint of the two series-connected third resistors, and convert the obtained voltage The difference is amplified to output the sensed current.

The current detector includes: a current comparator or a Hall current detector.

An electronic device with a power loss detection function, the electronic device comprising: a rectifier, a voltage detector, a current detector, a DC-to-DC converter, a first analog-to-digital converter, a second analog-to-digital converter, a digital multiplier microcontroller; where,

The rectifier is used to convert the received AC power into DC power;

The voltage detector, coupled to the rectifier, is used to detect the voltage of the direct current and output a corresponding detection voltage;

The current detector, coupled to the rectifier, is used to detect the current of the direct current and output a corresponding detection current;

The DC-to-DC converter is coupled to the rectifier through the current detector, and is used to convert the voltage of the DC power into an output voltage and supply power to a load;

The first analog-to-digital converter, coupled to the voltage detector, is used to convert the detection voltage from an analog form to a digital form;

The second analog-to-digital converter, coupled to the current detector, is used to convert the detected current from an analog form to a digital form;

the digital multiplier, coupled to the first analog-to-digital converter and the second analog-to-digital converter, for multiplying the detection voltage in digital form and the detection current in digital form, And output detection power;

The microcontroller, coupled to the digital multiplier, is used to find out the corresponding power loss from a lookup table according to the detected power, and display it.

The voltage detector includes: two first resistors connected in series; wherein,

One end of the two series-connected first resistors is coupled to the rectifier to receive the direct current, and the other end is grounded, and a common node of the two series-connected first resistors outputs the detection voltage.

The voltage detector includes: two capacitors connected in series; wherein,

One end of the two series-connected capacitors is coupled to the rectifier to receive the direct current, and the other end is grounded, and a common node of the two series-connected capacitors outputs the detection voltage.

The current detector includes: a detection resistor, two second resistors connected in series, two third resistors connected in series, and a differential pressure amplifier; wherein,

The detection resistor has a first end and a second end, the first end is coupled to the rectifier to receive the direct current, and the second end is coupled to the direct current to direct current converter;

The two second resistors connected in series, one end of the two second resistors connected in series is coupled to the first end of the detection resistor, and the other end is grounded;

The two third resistors connected in series, one end of the two third resistors connected in series is coupled to the second end of the detection resistor, and the other end is grounded;

The differential pressure amplifier is used to make a difference between the voltage value output by the common joint of the two series-connected second resistors and the voltage output by the common joint of the two series-connected third resistors, and convert the obtained voltage The difference is amplified to output the sensed current.

The current detector includes: a current comparator or a Hall current detector.

The electronic device with power loss detection function provided by the present invention does not require additional power measuring instruments, and allows users to obtain the current power loss of the electronic device under limited cost conditions, which is simple and convenient to use.

Description of drawings

In order for those skilled in the art to further understand the features and technical content of the present invention, please refer to the following detailed description and accompanying drawings of the present invention. The accompanying drawings are only for reference and description, and are not intended to limit the present invention.

FIG. 1 is a block diagram of an electronic device with a power loss detection function provided by Embodiment 1 of the present invention;

2 is a schematic diagram of a specific circuit structure of an electronic device with a power loss detection function provided by Embodiment 1 of the present invention;

FIG. 3 is a timing diagram of an electronic device with a power loss detection function provided by Embodiment 1 of the present invention to control an A/D converter to output detected power in digital form through a clock signal;

FIG. 4 is a block diagram of an electronic device with a power loss detection function provided by Embodiment 2 of the present invention.

In the accompanying drawings, the list of parts represented by each label is as follows:

1, 1'-power supply, 11, 11'-rectifier, 12, 12'-voltage detector, 13, 13'-current detector, 14-DC to DC converter, 15-analog multiplier, 16- Analog to Digital Converter, 2-Electronic Device, 21-Load, 22-Motherboard, 221-Microcontroller, 222-Lookup Table, 4-Power Supply, 45-Digital Multiplier, 46-First Analog to Digital Converter 47-second analog-to-digital converter, 5-electronic device, BD1-bridge rectifier, C1-capacitor, OC1, OC2-optocoupler, OP1-operational amplifier, PD1, PD2-light emitting device, PT1, PT2 -Photodetector, Q1-switch, R1～R15-resistor, Rsen-sense resistor, L-live wire, N-neutral wire, Clk-clock signal, Idc-current of direct current, Isen-sense current in analog form, Isen'-detection current in digital form, Psen-detection power in analog form, Psen'-detection power in digital form, Vac-AC power supply, Vdc-voltage of direct current, Vout-output voltage, Vsen-detection voltage in analog form, Vsen' - sense voltage in digital form.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the implementation manner of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Example 1

FIG. 1 is a block diagram of an electronic device with a power loss detection function provided by Embodiment 1 of the present invention. Referring to FIG. 1 , the electronic device 2 with power loss detection function includes: a power supply 1 , a load 21 and a main board 22 .

Wherein, the power supply 1 is used to receive the AC power Vac and convert it into a DC output voltage Vout to supply power to the load 21 and the main board 22 .

In this embodiment, the power supply 1 includes a rectifier 11, a voltage detector 12, a current detector 13, a direct current to direct current (DC/DC) converter 14, an analog multiplier 15 and an analog to digital (A/D ) converter 16. Wherein, the load 21 is all the components in the electronic device 2 except the motherboard 22 that need power from the power supply 1 . For example, if the electronic device 2 is an LCD TV, the load 21 includes an inverter for driving CCFLs, a circuit for processing audio and video, and a speaker. The main board 22 is used to control the operation of the electronic device 2 , and it also needs to be powered by the power supply 1 , so it is also a load of the power supply 1 . In this embodiment, the motherboard 22 includes a microcontroller 221 and a look-up table 222 .

Wherein, the rectifier 11 is used to convert the received AC power Vac into a direct current; the voltage detector 12 is coupled to the rectifier 11, and is used to detect the voltage Vdc of the direct current output by the rectifier 11, and output a corresponding detection voltage Vsen; the current detector 13 is coupled to the rectifier 11, used to detect the current Idc of the direct current output by the rectifier 11, and output a corresponding detection current Isen; the DC/DC converter 14 is coupled to the rectifier 11 through the current detector 13, and is used to output the rectifier 11 The direct current voltage Vdc is converted into a direct current output voltage Vout to supply power to the load 21 and the main board 22; the analog multiplier 15 is coupled to the voltage detector 12 and the current detector 13, and is used for synchronizing the detection voltage Vsen and the detection current Isen Multiply, and output the detection power Psen of the analog form; A/D converter 16 is coupled to the analog multiplier 15, is used for converting the detection power Psen of the analog form into the detection power Psen' of the digital form; Microcontroller 221 is coupled To the A/D converter 16, for finding the corresponding power loss from the lookup table 222 according to the detected power Psen' in digital form, and displaying it.

FIG. 2 is a schematic diagram of a specific circuit structure of the electronic device 2 with a power loss detection function provided by Embodiment 1 of the present invention. Please refer to FIG. 2 , an electronic device 2' having a power loss detection function includes a power supply 1', a load 21 and a motherboard 22. Wherein, the power supply 1' includes a rectifier 11', a voltage detector 12', a current detector 13', a DC/DC converter 14, an analog multiplier 15, and an A/D converter 16, and the motherboard 22 includes a microcontroller 221 and lookup table 222. Here, the same component symbols shown in FIG. 2 and those shown in FIG. 1 represent the same components.

Generally, the AC power Vac used in the market has a high voltage of 90-264Vrms, so the rectifier 11' shown in Figure 2 is often used to convert AC to DC. The rectifier 11' includes a bridge rectifier BD1 and a capacitor C1 having a large capacitance value. The bridge rectifier BD1 is a full-wave rectifier, which uses four diodes to form a bridge, so that the bridge rectifier BD1 has current flowing in the positive and negative half cycles of the AC power supply Vac voltage, and forms a unidirectional full-wave rectifier at the output end. pulsating DC voltage. The terminals of the bridge rectifier BD1 are usually marked with "~", "+", and "-" symbols, and the two ends marked with "~" symbols are AC input terminals, which are respectively coupled to the live wire of the commercial AC power supply Vac (live wire) L and neutral wire (neutral wire) N, and the two ends marked with "+" and "-" symbols are direct current output ends, which are respectively coupled to both ends of the capacitor C1. Capacitor C1 is used to filter the full-wave pulsating DC voltage, reducing the voltage ripple and turning it into a stable DC voltage Vdc.

The voltage detector 12' includes two first resistors R1 and R2 connected in series. One end of the first resistors R1 and R2 connected in series is coupled to the rectifier 11' for receiving the voltage Vdc of the direct current output by the rectifier 11', and the other end of the resistors R1 and R2 connected in series is grounded; therefore, the first resistor After R1 and R2 are connected in series, both ends are respectively coupled to both ends of the capacitor C1 (or the DC output end of the bridge rectifier BD1 marked with "+" and "-"). The two first resistors R1 and R2 connected in series divide the voltage at the terminal of the capacitor C1, and output the detection voltage Vsen at the common junction of the first resistors R1 and R2. Since the terminal voltage of the capacitor C1 is the voltage Vdc of the direct current output by the rectifier 11', the detection voltage Vsen is proportional to the voltage Vdc of the direct current. In design, the resistance value of R1 in the first resistor is much greater than the resistance value of R2 in the first resistor, so that the level of the detection voltage Vs en is suitable for subsequent circuit processing. Among them, R1 and R2 in the first resistor shown in Figure 2 can also be replaced by capacitors C1 and C2 respectively. At this time, the capacitance value of capacitor C1 must be designed to be much smaller than the capacitance value of capacitor C2, so that the detection voltage Vsen It is suitable for the processing of subsequent circuits.

Wherein, the current detector 13' includes: a detection resistor Rsen, two second resistors R3 and R4 connected in series, and two third resistors R5 and R6 connected in series. Wherein, the detection resistor Rsen has a first terminal and a second terminal, which are used to convert the current Idc of the direct current output by the rectifier 11' into a corresponding voltage, and this voltage value is the voltage at the first terminal and the second terminal of the detection resistor Rsen. voltage difference. The first end of the detection resistor Rsen is coupled to the rectifier 11' for receiving the output DC current Idc, and the second end of the detection resistor Rsen is coupled to the input end of the DC/DC converter 14; therefore, the detection resistor Rsen The first end is coupled to the non-ground end of the capacitor C1 (or the DC output end of the bridge rectifier BD1 marked with a "+" sign). After the second resistors R3 and R4 are connected in series, one end is coupled to the first end of the detection resistor Rsen, and the other end of the series connection of R3 and R4 is grounded, so the second resistors R3 and R4 are connected to the first end voltage of the detection resistor Rsen The voltage is divided, and the first detection voltage is output at the common junction of the second resistors R3 and R4. One end of the third resistors R5 and R6 connected in series is coupled to the second end of the detection resistor Rsen, and the other end of the third resistors R5 and R6 connected in series is grounded, so the third resistors R5 and R6 are connected to the second end of the detection resistor Rsen. The voltage at the second terminal is divided, and the second detection voltage is output at the common junction of the third resistors R5 and R6. Finally, the difference between the first detection voltage and the second detection voltage is amplified and output as the detection current Isen through the differential pressure amplifier (which is composed of the operational amplifier OP1 and resistors R7-R10), so the detection current Isen is It is in the form of a voltage and is proportional to the current Idc of the direct current. Wherein, the current detector can also be replaced by a current detector or a Hall (Hall) current detector.

Since the voltage Vdc and current Idc of the direct current output by the rectifier 11' are direct current signals obtained through the filtering of the capacitor C1 in it, there is no virtual work problem caused by the phase angle difference of the alternating current signal, and the electronic device 2' is measuring The virtual work is not charged for power or electricity pricing, so the simplest real power can be obtained by detecting the voltage Vdc and current Idc filtered by the capacitor C1. In addition, because the DC/DC converter 14 often includes a transformer, since the transformer has an electrical isolation function, the rectifier 11', the voltage detector 12', the current detector 13', the analog multiplier 15 and the A/D converter 16 is a component on the high-voltage side, and the load 21 and the main board 22 are components on the low-voltage side. Since the A/D converter 16 on the high-voltage side transmits the detection power Psen' in digital form to the microcontroller 221 in the main board 22 on the low-voltage side, it must be done through the optocoupler OC1 as shown in FIG. 2 . Similarly, the clock signal Clk output by the microcontroller 221 in the motherboard 22 must also be transmitted to the A/D converter 16 through the optocoupler OC2 shown in FIG. 2 .

Fig. 3 is a timing diagram of the electronic device 2' having the power loss detection function provided by Embodiment 1 of the present invention controlling the A/D converter 16 to output the detected power Psen' in digital form through the clock signal Clk. Please refer to Figure 2 and Figure 3 at the same time, for example, the value range of the detection power Psen in analog form is 0~30W, while the value of detection power Psen' in digital form is 8-bit data, that is, 8 binary numbers D7~D0 Indicates the detection power Psen' in digital form, and its value ranges from 00000000 to 11111111. When the A/D converter 16 converts the received detection power Psen in analog form into the detection power Psen' in digital form, it does not output it immediately, but waits for the microprocessor 221 in the main board 22 to send a clock signal Clk , the A/D converter 16 sends one bit data of the detection power Psen' in digital form to the microprocessor 221, for example, from MSB (Most Significant Bit, most significant bit) D7 to LSB (Least Significant Bit, least significant bit) successively ) D0 sequence to transmit data on all bits.

In this embodiment, the clock signal Clk sent by the microprocessor 221 in the main board 22 is at a high level, and this high level controls the conduction of the switch Q1 through the current limiting and voltage division of the resistors R13 and R14. After the switch Q1 is turned on, the DC power supply with a voltage of 5V is connected to the light-emitting device PD2 in the optocoupler OC2 through the resistor R12 and the turned-on switch Q1. Since there is current flowing, the light-emitting device PD2 emits light, and the photocoupler The photodetector PT2 in the device OC2 is turned on due to the detection of light, so the A/D converter 16 receives the low level generated by grounding and passes the data on one bit of the detection power Psen' in digital form through the light The coupler OC1 sends to the microprocessor 221. In addition, when the microprocessor 221 does not send the clock signal Clk, the microprocessor 221 can be converted to an output low level, and the low level controls the switch Q1 to be disconnected. Since the control switch Q1 is disconnected at this time, the voltage is 5V. The DC power supply cannot be connected to the light-emitting device PD2, so the light-emitting device PD2 cannot emit light because there is no current flowing through it, and the photodetector PT2 in the optocoupler OC2 is disconnected because no light is detected, so the A/D converter 16 The received DC power with a voltage of 5V generates a high level through the resistor R15 and no longer transmits data to the microprocessor 221 .

After the microprocessor 221 sends out 8 clock signals Clk (clock signals C1k marked as 1-8 as shown in FIG. 3 ), the microprocessor 221 will receive a complete detection power Psen' in digital form. The power loss value corresponding to the detected power Psen' in digital form can be found from the look-up table 222, and displayed to the user, so that the user can know the current power loss of the electronic device 2', wherein the look-up table 222 is The built-in non-volatile memory (not marked in the figure) of the main board 22 records the corresponding power consumption value of each digital data between 00000000-11111111. For example, when the detected power Psen' in digital form received by the microprocessor 221 is 01001111, the microprocessor 221 can find out from the lookup table 222 that the corresponding power loss value is 9.2575W.

Example 2

FIG. 4 is a block diagram of an electronic device with a power loss detection function provided by Embodiment 2 of the present invention. Please refer to FIG. 4 , the electronic device 5 with power loss detection function includes a power supply 4 , a load 21 and a motherboard 22 . Wherein, the power supply 4 includes a rectifier 11, a voltage detector 12, a current detector 13, a DC/DC converter 14, a first analog-to-digital (A/D) converter 46, a second analog-to-digital (A/D ) converter 47 and digital multiplier 45 , and the motherboard 22 includes a microcontroller 221 and a look-up table 222 . Here, the same component symbols shown in FIG. 4 and those shown in FIG. 1 represent the same components.

The rectifier 11 is used to convert the received AC power Vac into DC power. The voltage detector 12 is coupled to the rectifier 11 for detecting the voltage Vdc of the direct current output by the rectifier 11, and outputs a corresponding detection voltage Vsen; the current detector 13 is coupled to the rectifier 11 for detecting the current of the direct current output by the rectifier 11 Idc, and output the corresponding detection current Isen; the DC/DC converter 14 is coupled to the rectifier 11 through the current detector 13 to convert the DC voltage Vdc output by the rectifier 11 into a DC output voltage Vout to supply power to the load 21 and the main board 22; the first A/D converter 46 is coupled to the voltage detector 12, and is used to convert the received analog detection voltage Vsen into a digital detection voltage Vsen'; the second A/D converter 47 is coupled Connected to the current detector 13 for converting the received analog detection current Isen into a digital detection current Isen'; the digital multiplier 45 is coupled to the first A/D converter 46 and the second A/D converter The device 47 is used to multiply the detection voltage Vsen' in digital form and the detection current Isen' in digital form, and output the detection power Psen' in digital form; the microcontroller 221 is coupled to the digital multiplier 45 for digital form The detected power Psen' finds the corresponding power loss from the lookup table 222 and displays it.

In summary, the electronic device with power loss detection function of the present invention detects the voltage and current between the rectifier of the power supply and the DC-to-DC converter, and multiplies the detected voltage and current to obtain the load The consumed energy corresponds to the detection power, and then the microcontroller finds the corresponding power loss from the lookup table according to the detection power, which is the power drawn by the load, and displays it. Therefore, the electronic device with power loss detection function of the present invention can allow users to obtain the current power loss of the electronic device under the condition of limited cost without using additional power measuring instruments.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All other equivalent changes or modifications made within the scope of the characteristics of the present invention shall be included in the patent scope of the present invention.

Claims (8)

1. An electronic device having a power loss detection function, the electronic device comprising: the device comprises a rectifier, a voltage detector, a current detector, a direct current-direct current converter, an analog multiplier, an analog-digital converter and a microcontroller; wherein,

the rectifier is used for converting the received alternating current power supply into direct current;

the voltage detector is coupled to the rectifier and used for detecting the voltage of the direct current and outputting corresponding detected voltage;

the current detector is coupled to the rectifier and is used for detecting the current of the direct current and outputting a corresponding detection current;

the direct current-to-direct current converter is coupled to the rectifier through the current detector, and is used for converting the voltage of the direct current into an output voltage and supplying power to a load;

the analog multiplier is coupled to the voltage detector and the current detector, and is used for multiplying the detection voltage and the detection current and outputting detection power;

the analog-to-digital converter is coupled to the analog multiplier and used for converting the detection power from an analog form to a digital form;

the microcontroller is coupled to the analog-to-digital converter and used for finding out corresponding power loss from a lookup table according to the detection power in a digital form and displaying the power loss;

the current detector includes: the voltage difference amplifier comprises a detection resistor, two second resistors connected in series, two third resistors connected in series and a voltage difference amplifier; wherein,

the detection resistor has a first end and a second end, the first end is coupled to the rectifier to receive the direct current, and the second end is coupled to the direct current-to-direct current converter;

the two serially connected second resistors have one end coupled to the first end of the detection resistor and the other end grounded;

one end of the two serially connected third resistors is coupled to the second end of the detection resistor, and the other end of the two serially connected third resistors is grounded;

and the voltage difference amplifier is used for making a difference between the voltage value output by the common joint of the two second resistors connected in series and the voltage value output by the common joint of the two third resistors connected in series, and amplifying the obtained voltage difference value to output the detection current.

2. The electronic device with power loss detection function according to claim 1, wherein the voltage detector includes: two first resistors connected in series; wherein,

one end of the two first resistors connected in series is coupled to the rectifier to receive the direct current, the other end of the two first resistors connected in series is grounded, and a common joint of the two first resistors connected in series outputs the detection voltage.

3. The electronic device with power loss detection function according to claim 1, wherein the voltage detector includes: two capacitors connected in series; wherein,

one end of each of the two serially connected capacitors is coupled to the rectifier to receive the direct current, the other end of each of the two serially connected capacitors is grounded, and a common junction of the two serially connected capacitors outputs the detection voltage.

4. The electronic device with power loss detection function according to claim 1, wherein the current detector includes: current transformers or hall current detectors.

5. An electronic device having a power loss detection function, the electronic device comprising: the device comprises a rectifier, a voltage detector, a current detector, a direct current-direct current converter, a first analog-to-digital converter, a second analog-to-digital converter, a digital multiplier and a microcontroller; wherein,

the rectifier is used for converting the received alternating current power supply into direct current;

the voltage detector is coupled to the rectifier and used for detecting the voltage of the direct current and outputting corresponding detected voltage;

the current detector is coupled to the rectifier and is used for detecting the current of the direct current and outputting a corresponding detection current;

the direct current-to-direct current converter is coupled to the rectifier through the current detector, and is used for converting the voltage of the direct current into an output voltage and supplying power to a load;

the first analog-to-digital converter, coupled to the voltage detector, for converting the detected voltage from an analog form to a digital form;

the second analog-to-digital converter, coupled to the current detector, for converting the detected current from an analog form to a digital form;

the digital multiplier is coupled to the first analog-to-digital converter and the second analog-to-digital converter, and is used for multiplying the detection voltage in a digital form and the detection current in a digital form and outputting detection power;

the microcontroller is coupled to the digital multiplier and used for finding out corresponding power loss from a lookup table according to the detected power and displaying the power loss;

the current detector includes: the voltage difference amplifier comprises a detection resistor, two second resistors connected in series, two third resistors connected in series and a voltage difference amplifier; wherein,

the detection resistor having a first end coupled to the rectifier to receive the DC power and a second end coupled to the DC-to-DC converter;

the two series-connected second resistors, one end of which is coupled to the first end of the detection resistor and the other end of which is grounded;

the two series-connected third resistors, one end of which is coupled to the second end of the detection resistor and the other end of which is grounded;

and the voltage difference amplifier is used for making a difference between the voltage value output by the common joint of the two second resistors connected in series and the voltage value output by the common joint of the two third resistors connected in series, and amplifying the obtained voltage difference value to output the detection current.

6. The electronic device with power loss detection function according to claim 5, wherein the voltage detector includes: two first resistors connected in series; wherein,

one end of the two first resistors connected in series is coupled to the rectifier to receive the direct current, the other end of the two first resistors connected in series is grounded, and a common joint of the two first resistors connected in series outputs the detection voltage.

7. The electronic device with power loss detection function according to claim 5, wherein the voltage detector includes: two capacitors connected in series; wherein,

one end of the two serially connected capacitors is coupled to the rectifier to receive the direct current, the other end of the two serially connected capacitors is grounded, and the common joint of the two serially connected capacitors outputs the detection voltage.

8. The electronic device with power loss detection function according to claim 5, wherein the current detector includes: current transformers or hall current detectors.

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