TWI420289B - Power supply alarming circuit - Google Patents

Description

Power alarm circuit

The invention relates to a power supply alarm circuit, in particular to a multi-phase power supply alarm circuit of a computer.

The power source is the heart of an electronic system that provides the energy needed for an electronic device that plays an important role in the electronic system. With the rapid development of electronic products, the power supply technology that supplies energy must also develop simultaneously, otherwise it will restrict the development of electronic products. Especially for communication and computer products, almost all of these products use switching power supplies. For computer products, multi-phase switching power supply technology is often used, and the multi-phase power supply is switched in turn during normal operation. However, in the absence of phase, that is, in a multi-phase power supply, if one phase or some phase power supply is abnormal and the other phase power supply output pulse waves are normal, the system cannot detect the power supply abnormality. As a result, the power load of the normal output of other phases is increased, which will endanger the safety and life of the power supply, and in severe cases, the power supply will be burnt.

In view of the above, it is necessary to provide a power alarm circuit to alarm when the computer power output is abnormal.

A power supply alarm circuit includes a sampling circuit and an alarm circuit. The sampling circuit includes a control switch. The input end of the sampling circuit is connected to a power signal output end. The sampling circuit is connected to the input end of the alarm circuit through a control switch thereof. When the power When there is no signal output at the signal output end, the control switch does not conduct, and the alarm circuit is driven to alarm.

The power alarm circuit detects the computer power through a simple resistor, capacitor, diode, transistor and buzzer, and can alarm in time when the computer power output is abnormal.

1, 2, 3‧‧‧ sampling circuit

100, 110, 120‧‧ ‧ integration circuit

200, 210, 220‧ ‧ div.

300, 310, 320‧‧‧ indicating circuits

400‧‧‧ alarm circuit

A, B, C‧‧‧ power signal output

R1~R14, R22‧‧‧ resistance

D1~D3, D8, D9‧‧‧ diode

D4~D6, D7‧‧‧Lighting diode

Q1‧‧‧Optoelectronics

Q2~Q4‧‧‧ Field Effect Crystal

Vcc‧‧‧ power supply

LS1‧‧‧ buzzer

1 is a circuit diagram of a preferred embodiment of a power supply alarm circuit of the present invention.

Referring to FIG. 1, a preferred embodiment of the power alarm circuit of the present invention is used to indicate whether the A, B, and C three-phase power supplies of the computer are working normally. The power alarm circuit includes sampling circuits 1, 2, 3 and an alarm circuit 400 for sampling and indicating whether the phase A power is normal. The sampling circuit 2 is for sampling and indicating whether the phase B power is normal. The sampling circuit 3 is used for sampling and indicating whether the C-phase power supply is normal. The alarm circuit 400 is used to indicate whether the A, B, and C three-phase power supplies of the computer are working normally and alarm when any one of the A, B, and C three-phase power sources is abnormal.

The sampling circuit 1 includes a diode D1, an integrating circuit 100, a voltage dividing circuit 200, an indicating circuit 300, and a control switch.

The anode of the diode D1 is connected to the output terminal of the A phase power signal, and the cathode is connected to the input end of the integrating circuit 100.

The integrating circuit 100 includes a resistor R1 and a capacitor C1. One end of the resistor R1 is connected to the cathode of the diode D1 as an input end of the integrating circuit 100. The other end of the resistor R1 is connected to one end of the capacitor C1, and the other end of the capacitor C1 is connected. Ground.

The voltage dividing circuit 200 includes two resistors R2 and R3, and one end of the resistor R2 is the same as the resistor R1 and the electric The node between the capacitors C1 is connected, the other end of the resistor R2 is connected to one end of the resistor R3, and the other end of the resistor R3 is grounded.

The indicating circuit 300 includes a resistor R12 and a light-emitting diode D4. One end of the resistor R12 is connected to a node between the resistors R2 and R3, and the other end of the resistor R12 is connected to the anode of the LED D4. The cathode of the pole body D4 is grounded.

The control switch is an N-channel MOS type field effect transistor Q2, and the gate of the field effect transistor Q2 is connected to a node between the resistors R2 and R3, and the field effect transistor Q2 has the same polarity as the alarm circuit. The inputs of the 400 are connected.

The sampling circuit 2 includes a diode D2, resistors R4, R5, R6, and R13, a capacitor C2, a light-emitting diode D5, and an N-channel MOS field effect transistor Q3. The anode of the diode D2 is connected to the phase B. Power signal output. The sampling circuit 2 includes a connection between components and a similar component diode D1 of the sampling circuit 1, resistors R1, R2, R3, R12, a capacitor C1, a light-emitting diode D4, and an N-channel MOS field. The connection between the effect transistors Q2 is the same, the resistor R4 and the capacitor C2 form the integration circuit 110, the resistors R5 and R6 form the voltage dividing circuit 210, the resistor R13 and the light-emitting diode D5 form the indicating circuit 310, and the field effect transistor Q3 To control the switch, it will not be described here. The drain of the field effect transistor Q3 is connected to the source of the field effect transistor Q2.

The sampling circuit 3 includes a diode D3, resistors R7, R8, R9, R14, a capacitor C3, a light-emitting diode D6, and an N-channel MOS type field effect transistor Q4. The anode of the diode D3 is connected to the phase C. Power signal output. The sampling circuit 3 includes a connection between components and a similar component diode D1 of the sampling circuit 1, resistors R1, R2, R3, R12, a capacitor C1, a light-emitting diode D4, and an N-channel MOS field. The connection between the effect transistor Q2 The same formula, the resistor R7, the capacitor C3 constitutes the integral circuit 120, the resistors R8, R9 constitute the voltage dividing circuit 220, the resistor R14, the light-emitting diode D6 constitutes the indicating circuit 320, and the field effect transistor Q4 is the control switch, no longer Narration. The drain of the field effect transistor Q4 is connected to the source of the field effect transistor Q3, and the source of the field effect transistor Q4 is grounded.

The alarm circuit 400 includes an NPN transistor Q1, a buzzer LS1, resistors R10, R11, and R22, diodes D8 and D9, and a light-emitting diode D7. The base of the transistor Q1 is the same as the diode. The cathode of the body D8 is connected, the anode of the diode D8 is connected to a power source Vcc through the resistor R11, the anode of the diode D8 is also connected to the anode of the diode D9, and the cathode of the diode D9 serves as an alarm circuit. The input end of the diode is connected to the drain of the field effect transistor Q2, the cathode of the diode D9 is also connected to the cathode of the light emitting diode D7, and the anode of the light emitting diode D7 is connected to the power source Vcc through the resistor R10. The collector of the transistor Q1 is connected to one end of the resistor R22 through the buzzer LS1, and the other end of the resistor R22 is connected to the power source Vcc, and the emitter of the transistor Q1 is grounded.

When the three-phase power supplies of A, B, and C are all working normally, the digital signal signals output from the A, B, and C three-phase power signal output terminals are respectively converted by the digital-to-analog of the respective integration circuits 100, 110, and 120. The voltage division of the voltage circuits 200, 210, 220 provides voltage control signals to the indication circuits 300, 310, and 320. The LEDs D4, D5, and D6 are both illuminated to indicate that the three-phase power sources of the A, B, and C are normal. At the same time, the field effect transistors Q2, Q3 and Q4 are both turned on so that the light emitting diode D7 emits light to indicate that the power supply is working normally, and the base of the transistor Q1 is turned off at a low level, and the buzzer LS1 does not sound at this time.

When there is no output in any of the A, B, and C three-phase power supplies, the output of the A-phase power supply is taken as an example. At this time, the A-phase power signal output end has no digital pulse signal output, and the LED diode D4 is not lit. The A phase power supply is abnormal, and the B and C two-phase power signal output terminals output normally. The digital pulse signals are respectively converted by the digital-to-analog conversion of the respective integrating circuits 110, 120, and the voltage dividing circuits 210, 220 are divided to provide voltage control signals to the indicating circuits 310, 320, and the light-emitting diodes D5 and D6 emit light. Instructing the two-phase power supply of B and C to be normal, and the field-effect transistors Q2, Q3, and Q4 are all turned off, so that the light-emitting diode D7 does not emit light, indicating that the power supply is abnormal, and the base of the transistor Q1 is extremely high and turned on. At this time, the buzzer LS1 emits a sound alarm.

The power alarm circuit detects the computer power through a simple resistor, capacitor, diode, transistor and buzzer, and can alarm in time when the computer power output is abnormal. The diodes D1, D2 and D3 can prevent the capacitors C1, C2 and C3 from discharging to the A, B and C three-phase power signal output terminals, respectively. The diode D9 can avoid the false illumination of the LED D7 when the power signal output terminal is abnormal in the A, B, C three-phase power supply, and the diode D8 can cancel the voltage raised by the anode of the diode D9, avoiding When the three-phase power supplies of A, B, and C are all working normally, the error of the transistor Q1 is turned on, and the buzzer LS1 emits a sound.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

1, 2, 3‧‧‧ sampling circuit

100, 110, 120‧‧ ‧ integration circuit

200, 210, 220‧ ‧ div.

300, 310, 320‧‧‧ indicating circuits

400‧‧‧ alarm circuit

A, B, C‧‧‧ power signal output

R1~R14, R22‧‧‧ resistance

D1~D3, D8, D9‧‧‧ diode

D4~D6, D7‧‧‧Lighting diode

Q1‧‧‧Optoelectronics

Q2~Q4‧‧‧ Field Effect Crystal

Vcc‧‧‧ power supply

LS1‧‧‧ buzzer

Claims (11)

A power supply alarm circuit includes a sampling circuit and an alarm circuit. The sampling circuit includes a control switch. The input end of the sampling circuit is connected to a power signal output end, and the sampling circuit is connected to the input end of the alarm circuit through a control switch thereof. When the power signal output end has no signal output, the control switch is not turned on, and the alarm circuit alarms, wherein the sampling circuit further includes an integrating circuit, a voltage dividing circuit and an indicating circuit, and the input end of the integrating circuit is used as a sampling An input end of the circuit is connected to the power signal output end, and an input end of the voltage dividing circuit is connected to an output end of the integrating circuit, and an output end of the voltage dividing circuit is respectively connected to the indicating circuit and the control switch, when the power signal is When the output end outputs the pulse wave signal, the integrating circuit outputs an analog signal, and the voltage dividing circuit outputs a voltage control signal to make the control switch be turned on, and the alarm circuit does not alarm. The power alarm circuit of claim 1, wherein the integrating circuit and the power signal output end are connected to a diode. The power supply alarm circuit of claim 1, wherein the integration circuit comprises a first resistor and a capacitor, the first resistor is used as an input end of the integration circuit, and the other end of the first resistor is coupled to the voltage divider. The circuit is connected and connected to one end of the capacitor, and the other end of the capacitor is grounded. The power supply alarm circuit of claim 3, wherein the voltage dividing circuit comprises a second resistor and a third resistor, and one end of the second resistor is connected to a node between the first resistor and the capacitor, The other end of the second resistor is connected to the control switch and connected to one end of the third resistor, and the other end of the third resistor is grounded. The power alarm circuit of claim 4, wherein the control switch is An N-channel MOS type field effect transistor, wherein a gate of the field effect transistor is connected to a node between the second resistor and the third resistor, and a drain of the field effect transistor is connected to an input end of the alarm circuit The source of the field effect transistor is grounded. The power alarm circuit of claim 5, wherein the alarm circuit comprises an NPN type transistor, a buzzer, a fourth resistor and a fifth resistor, and the base of the NPN transistor acts as an alarm. The input end of the circuit is connected to the drain of the field effect transistor, and the base of the NPN type transistor is further connected to a power source through the fourth resistor, and the collector is connected to the fifth resistor end through the buzzer, the fifth resistor The other end is connected to the power source, and the emitter of the NPN type transistor is grounded. The power alarm circuit of claim 6, wherein the alarm circuit further includes a sixth resistor, a first light emitting diode, a first diode, and a second diode, the first The anode of the light emitting diode is connected to the power source through the fourth resistor, and the cathode of the first light emitting diode is respectively connected to the drain of the field effect transistor and the cathode of the first diode, the first diode The anode is connected to the power source through the sixth resistor, the anode of the first diode is also connected to the anode of the second diode, and the cathode of the second diode is connected to the base of the NPN transistor. The power alarm circuit of claim 4, wherein the indicating circuit comprises a seventh resistor and a second LED, and a node between the seventh resistor and the second resistor and the third resistor Connected, the other end of the seventh resistor is connected to the anode of the second LED, and the cathode of the second LED is grounded. A power alarm circuit includes at least two connected sampling circuits and an alarm circuit, each sampling circuit includes a control switch, and an input end of each sampling circuit is connected to a corresponding power signal output end, and one end of the control switch of the sampling circuit Interconnected, wherein the other end of the control switch of the sampling circuit is connected to the input end of the alarm circuit The other end of the control switch of the other sampling circuit is grounded. When there is no output at any of the power signal output terminals, the control switches are not turned on, and the alarm circuit alarms, wherein each sampling circuit further includes an integrating circuit and a partial voltage a circuit, the input end of each integrating circuit is connected as an input end of the corresponding sampling circuit to a corresponding power signal output end, and an input end of each voltage dividing circuit is connected to an output end of the corresponding integrating circuit, and each voltage dividing circuit The output end is connected with the corresponding control switch. When the power signal output ends output the pulse signal, the corresponding integral circuit outputs an analog signal, and the corresponding voltage dividing circuit outputs a voltage control signal so that the corresponding control switch is turned on. The alarm circuit does not alarm. The power alarm circuit of claim 9, wherein each of the integrating circuits and the corresponding power signal output end are respectively connected with a diode. The power supply alarm circuit of claim 9, wherein the control switch of the sampling circuit is an N-channel MOS type field effect transistor, and the gate thereof is connected to an output end of the corresponding voltage dividing circuit, one of which is The source of the control switch of the sampling circuit is connected to the drain of the control switch of the other sampling circuit, and the drain of the control switch of one of the sampling circuits is connected to the input end of the alarm circuit, and the control switch of the other sampling circuit The source is grounded.