Alternating current priority alternating current and direct current power supply system for computer

Abstract

The invention relates to a computer alternating-current priority alternating-current and direct-current power supply system, and belongs to the technical field of power supplies. The system comprises an AC / DC circuit (12), a first redundant circuit (13), a DC / DC circuit (14), a control circuit (22), a switching circuit (32) and a second redundant circuit (33). According to the invention, a signal in the AC / DC circuit controls the on and off of the switching tube through the control circuit, so that the power supply of the battery is controlled, the purpose of preferentially supplying power to equipment by alternating current is achieved, and the circuit has the advantages of small size, high efficiency, low loss, low cost, easiness in implementation and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of power supply, and in particular relates to an AC-prioritized AC-DC power supply system for computers. Background Art

[0002] In computers, the computer power supply is generally AC input, and the DC output is 12V, 5V and 3.3V to the motherboard switch board, etc. Some computers also have a DC input of 28V, which is also stepped down to 12V, 5V and 3.3V. In some power supply systems, both AC and DC are included, where the AC input is 220Vac / 50Hz and the DC input is a 24V battery. It is required that AC and DC power the equipment at the same time. When the AC power is disconnected, the battery can maintain the normal operation of the equipment. Similar to this system, UPS power supply is a typical representative. However, UPS power supply needs to be converted into AC power through an inverter device, and then converted into DC power through rectification to power the computer. This method has a large inverter device and is not suitable for most computer equipment power supply solutions. For computer AC and DC power supply systems, the most efficient and small solution is to rectify AC power into 28V DC power, and then convert it into 12V, 5V and 3.3V through a step-down circuit to power each board. In this solution, 28V DC power and battery power are placed backflow through their respective redundant circuits.

[0003] Traditional AC / DC power supply Figure 1 As shown, the AC power passes through the AC / DC circuit and the redundant circuit to power the DC / DC circuit, and outputs Vo1, Vo2, and Vo3 to the computer board. Another battery outputs DC power and also powers the DC / DC circuit through the redundant circuit. Usually, when AC is powered, the voltage converted from AC to DC is higher than the battery power supply voltage. This ensures that when AC is powering the device, the battery does not supply power, ensuring that the battery is fully charged. However, when the AC-to-DC voltage is lower than the battery voltage, this power supply method cannot protect the battery power.

[0004] Therefore, an AC-priority AC-DC power supply system is needed, that is, when AC power is supplied, only AC power works and the battery does not power the equipment. When the AC power supply is disconnected, DC power is quickly cut in to power the equipment. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] The technical problem to be solved by the present invention is how to provide a computer AC priority AC / DC power supply system to solve the problem that the traditional AC / DC power supply cannot protect the battery power when the AC-to-DC voltage is lower than the battery voltage.

[0007] (II) Technical solution

[0008] In order to solve the above technical problems, the present invention provides a computer AC priority AC / DC power supply system, the system comprising: an AC / DC circuit (12), a first redundant circuit (13), a DC / DC circuit (14), a control circuit (22), a switch circuit (32) and a second redundant circuit (33);

[0009] The AC input is to the AC / DC circuit (12), the AC / DC circuit (12) outputs to the first redundant circuit (13), the first redundant circuit (13) outputs to the DC / DC circuit (14), the AC / DC circuit (12) gives a signal to the control circuit (22), the control circuit (22) outputs a signal to the switch circuit (32), the DC input is connected to the switch circuit (32), the output of the switch circuit (32) is connected to the DC / DC circuit (14) through the second redundant circuit (13), and the DC / DC circuit (14) outputs three voltages Vo1, Vo2, and Vo3.

[0010] (III) Beneficial effects

[0011] The present invention proposes a computer AC-priority AC-DC power supply system. The present invention provides a computer AC-priority AC-DC power supply system, which controls the on and off of the switch tube through the control circuit through the signal in the AC / DC circuit to realize the control of the battery power supply, thereby achieving the purpose of AC-priority powering the device. The use of this AC-priority AC-DC power supply system has the advantages of small circuit volume, high efficiency, low loss, low cost, easy implementation, etc., avoids the battery power loss after the AC and battery are powered at the same time, and ensures that the battery can have sufficient power to power the device after abnormal power failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Provide a block diagram of the AC and DC power supply system for traditional computers;

[0013] Figure 2 It is a block diagram of the improved AC / DC power supply system of the present invention;

[0014] Figure 3 For control and switching circuits. DETAILED DESCRIPTION

[0015] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples.

[0016] The object of the present invention is to provide an AC-priority AC / DC power supply system, comprising: an AC / DC circuit (12), a first redundant circuit (13), a DC / DC circuit (14), a control circuit (22), a switch circuit (32) and a second redundant circuit (33). The control circuit (22) comprises: an isolation optical coupler B1, a voltage divider resistor R1, a voltage divider resistor R3, a voltage divider resistor R4, and a transistor Q2; the switch circuit (32) comprises: a MOS transistor Q1 and a resistor R2.

[0017] The AC input is to the AC / DC circuit (12), the AC / DC circuit (12) outputs to the first redundant circuit (13), the first redundant circuit (13) outputs to the DC / DC circuit (14), the AC / DC circuit (12) gives a signal to the control circuit (22), the control circuit (22) outputs a signal to the switch circuit (32), the DC input is connected to the switch circuit (32), the DC input is a battery, the switch circuit (32) output is connected to the DC / DC circuit (14) through the second redundant circuit (13), and the DC / DC circuit (14) outputs three voltages Vo1, Vo2, and Vo3.

[0018] like Figure 2 The improved AC / DC power supply system is composed of a block diagram. When the AC input is turned on, it is rectified into DC power through the AC / DC circuit, passes through the first redundant circuit, and then stepped down through the DC / DC circuit to power other boards. In the AC / DC circuit, AUX is high and the DC_GOOD signal is low. The switch circuit is disconnected by the control circuit, and the battery cannot power the DC / DC circuit. When the AC input is disconnected, the AC / DC circuit has no power input, so that AUX is low and the DC_GOOD signal is low. At this time, the control circuit turns on the switch circuit, and the DC input powers the DC / DC circuit through the switch circuit and the second redundant circuit. When the AC input is started again, the control circuit cuts off the switch circuit again to achieve AC priority.

[0019] Embodiment 1:

[0020] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments, but is not intended to limit the present invention.

[0021] like Figure 2 The figure is a block diagram of the improved AC / DC power supply system of the present invention. The system comprises: an AC / DC circuit (12), a first redundant circuit (13), a DC / DC circuit (14), a control circuit (22), a switch circuit (32) and a second redundant circuit (33).

[0022] The AC / DC circuit (12) rectifies the AC input Vac into a DC power Vdc. The AC / DC circuit (12) outputs a DC_GOOD signal and an AUX signal. When the AC / DC circuit (12) works normally, the DC_GOOD signal is at a low level and the AUX signal is at a high level. When the AC / DC circuit (12) does not work, the DC_GOOD signal is at a low level and the AUX signal is at a low level.

[0023] The first redundant circuit (13) and the second redundant circuit (33) are used to prevent the voltage of another parallel circuit from being too high, thereby damaging the output of the AC / DC circuit (12) or the battery.

[0024] A DC / DC circuit (14), in a computer power supply device, comprises three step-down power supplies, which respectively output 12V, 5V and 3.3V. The DC / DC circuit (14) can realize isolated step-down conversion and output a relatively low ripple voltage.

[0025] The control circuit (22) takes the DC_GOOD signal and the AUX signal output by the AC / DC circuit (12) as inputs, and outputs a VP signal to drive the subsequent stage through transformation by the control circuit (22).

[0026] The switch circuit (32) is mainly composed of a P-MOS tube and can realize the functions of on and off through control. When the switch circuit (32) is on, the DC input Vi outputs the DC output Vo through the switch circuit (32). When the switch circuit (32) is off, the DC input Vi cannot be output.

[0027] The control circuit (22) comprises: an isolation optical coupler B1, a voltage dividing resistor R1, a voltage dividing resistor R3, a voltage dividing resistor R4 and a transistor Q2; the switch circuit (32) comprises: a MOS transistor Q1 and a resistor R2; wherein the MOS transistor Q1 is a P-channel MOS transistor having three contacts, namely, a gate, a source and a drain; and the transistor Q2 is a PNP transistor having three contacts, namely, a base, a collector and an emitter.

[0028] like Figure 3 The control circuit and the switch circuit of the present invention are shown, wherein:

[0029] The switch tube Q1 is a P-channel MOS tube, the source is connected to the DC input Vi, the drain is connected to the DC output Vo, the gate is connected to the node M2, and the discharge resistor R2 is connected between the gate and the source;

[0030] Transistor Q2 is a PNP transistor, with the base connected to node M1, the collector connected to node M2, and the emitter connected in series with resistor R4 and then connected to GND;

[0031] The anode pin 1 of the primary side light emitting diode of the optocoupler B1 is connected to AUX, the cathode pin 2 is connected to DC_GOOD, and the secondary side of the optocoupler B1 is connected to a parallel resistor R3, wherein the collector pin 4 is connected to the node M1, and the emitter pin 3 is connected to GND;

[0032] One end of resistor R1 is connected to the DC input Vi, and the other end is connected to the node M1.

[0033] When AUX is at a high level and DC_GOOD is at a low level, the primary light-emitting diode of the optocoupler is lit, so that the node M1 is at a low level. The transistor Q2 is an NPN transistor. When the base voltage is at a low level, the transistor is not conducting, the node M2 ​​level is the same as the DC input Vi level, and the MOS tube Q1 is cut off and not conducting.

[0034] When AUX is at a low level and DC_GOOD is at a low level, the primary light-emitting diode of the optocoupler is not turned on. After voltage division by resistors R1 and R3, node M1 is at a high level, the be junction of transistor Q2 is forward biased, transistor Q2 is turned on, and the node M2 ​​level is lower than the DC input Vi level. At this time, MOS tube Q1 is turned on.

[0035] The present invention provides a computer AC-priority AC / DC power supply system, which controls the on and off of the switch tube through the control circuit through the signal in the AC / DC circuit, realizes the control of the battery power supply, so as to achieve the purpose of AC-priority powering the device. The use of this AC-priority AC / DC power supply system has the advantages of small circuit volume, high efficiency, low loss, low cost, easy implementation, etc., avoids the battery power loss after the AC and battery are powered at the same time, and ensures that the battery can have sufficient power to power the device after abnormal power failure.

[0036] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A computer AC priority AC / DC power supply system, characterized in that: The system comprises: an AC / DC circuit (12), a first redundant circuit (13), a DC / DC circuit (14), a control circuit (22), a switch circuit (32) and a second redundant circuit (33); The AC input is to the AC / DC circuit (12), the AC / DC circuit (12) outputs to the first redundant circuit (13), the first redundant circuit (13) outputs to the DC / DC circuit (14), the AC / DC circuit (12) gives a signal to the control circuit (22), the control circuit (22) outputs a signal to the switch circuit (32), the DC input is connected to the switch circuit (32), the output of the switch circuit (32) is connected to the DC / DC circuit (14) through the second redundant circuit (13), and the DC / DC circuit (14) outputs three voltages Vo1, Vo2, and Vo3.

2. The computer AC priority AC / DC power supply system according to claim 1, characterized in that: The DC input is battery.

3. The computer AC priority AC / DC power supply system according to claim 1, characterized in that: When the AC input is turned on, it is rectified into DC power through the AC / DC circuit, passes through the first redundant circuit, and then stepped down by the DC / DC circuit to power other boards. In the AC / DC circuit, AUX is high and the DC_GOOD signal is low. The switch circuit is disconnected through the control circuit, and the battery cannot power the DC / DC circuit.

4. The computer AC priority AC / DC power supply system according to claim 3, characterized in that: When the AC input is disconnected, the AC / DC circuit has no power input, so AUX is at a low level and the DC_GOOD signal is at a low level. At this time, the control circuit turns on the switch circuit, and the DC input supplies power to the DC / DC circuit through the switch circuit and the second redundant circuit; when the AC input is started again, the control circuit cuts off the switch circuit again to achieve AC priority.

5. The computer AC priority AC / DC power supply system according to claim 4, characterized in that: The AC / DC circuit (12) rectifies the AC input Vac into a DC power Vdc. The AC / DC circuit (12) outputs a DC_GOOD signal and an AUX signal. When the AC / DC circuit (12) works normally, the DC_GOOD signal is at a low level and the AUX signal is at a high level. When the AC / DC circuit (12) does not work, the DC_GOOD signal is at a low level and the AUX signal is at a low level.

6. The computer AC priority AC / DC power supply system according to claim 4, characterized in that: The first redundant circuit (13) and the second redundant circuit (33) prevent the voltage of another parallel circuit from being too high, thereby damaging the output of the AC / DC circuit (12) or the battery.

7. The computer AC priority AC / DC power supply system according to claim 4, characterized in that: The DC / DC circuit (14) includes three step-down power supplies, which respectively output 12V, 5V and 3.3V. The DC / DC circuit (14) realizes isolated step-down conversion and outputs a relatively low ripple voltage.

8. The computer AC priority AC / DC power supply system according to claim 4, characterized in that: The control circuit (22) takes the DC_GOOD signal and the AUX signal output by the AC / DC circuit (12) as inputs, and outputs a VP signal to drive the subsequent stage through transformation by the control circuit (22).

9. The computer AC priority AC / DC power supply system according to any one of claims 4 to 8, characterized in that: The control circuit (22) comprises: an isolation optical coupler B1, a voltage dividing resistor R1, a voltage dividing resistor R3, a voltage dividing resistor R4 and a transistor Q2; the switch circuit (32) comprises: a MOS transistor Q1 and a resistor R2; wherein the MOS transistor Q1 is a P-channel MOS transistor having three contacts, namely, a gate, a source and a drain; and the transistor Q2 is a PNP transistor having three contacts, namely, a base, a collector and an emitter.

10. The computer AC priority AC / DC power supply system according to claim 9, characterized in that: The switch tube Q1 is a P-channel MOS tube, the source is connected to the DC input Vi, the drain is connected to the DC output Vo, the gate is connected to the node M2, and the discharge resistor R2 is connected between the gate and the source; Transistor Q2 is a PNP transistor, with the base connected to node M1, the collector connected to node M2, and the emitter connected in series with resistor R4 and then connected to GND; The anode pin 1 of the primary side light emitting diode of the optocoupler B1 is connected to AUX, the cathode pin 2 is connected to DC_GOOD, and the secondary side of the optocoupler B1 is connected to a parallel resistor R3, wherein the collector pin 4 is connected to the node M1, and the emitter pin 3 is connected to GND; One end of resistor R1 is connected to the DC input Vi, and the other end is connected to the node M1; When AUX is high and DC_GOOD is low, the primary LED of the optocoupler is lit, so that the node M1 is low. The transistor Q2 is an NPN transistor. When the base voltage is low, the transistor is not conducting. The node M2 ​​level is the same as the DC input Vi level, and the MOS tube Q1 is cut off and not conducting. When AUX is at a low level and DC_GOOD is at a low level, the primary light-emitting diode of the optocoupler is not turned on. After voltage division by resistors R1 and R3, node M1 is at a high level, the be junction of transistor Q2 is forward biased, transistor Q2 is turned on, and the node M2 ​​level is lower than the DC input Vi level. At this time, MOS tube Q1 is turned on.

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