JPH02250630A - Power source circuit device with diode or-circuit - Google Patents

Abstract

PURPOSE:To prevent an output voltage from decreasing by interposing a diode between the voltage dividing point of a voltage dividing resistor at the output side of a diode OR-circuit and the voltage dividing point of an output voltage dividing resistor. CONSTITUTION:Power sources 1, 2 are connected in parallel with a load 3 through OR-diodes D#1, D#1. Voltage dividing resistors R11, R12, R21, R22 are connected to the anode sides of the diodes D#1, Dlj1, and output voltage dividing resistors R13, R14, R23, R24 for outputting feedback output voltage information to output voltage monitors 1A, 2A of the power sources 1, 2 are connected to the cathode sides. Diodes D1, D2 are connected between connecting points A1, B1, between A2, B2. Since corresponding diode D1, or D2 is conducted with the power source of lower output voltage to reduce the voltage dividing point voltage of the resistor, it can prevent the output voltage from further decreasing.

Description

[Detailed Description of the Invention] [Summary] Regarding a power supply circuit device with a co-diode OR (OR) circuit, in which a voltage sense point for monitoring the output voltage is provided on the cathode side of the OR diode, the output voltage is slightly lower. The purpose of this system is to prevent the output voltage of a power supply circuit from dropping further from a value slightly lower than the rated voltage. In a power supply circuit device with a diode-OR circuit that is equipped with an OR diode to prevent backflow to the An output voltage divider resistor is connected to take out output voltage information for feedback to the output voltage monitoring section.

A diode is inserted between the voltage dividing point of the voltage dividing resistor and the voltage dividing point of the output voltage dividing resistor to allow conduction from the output voltage dividing resistor side to the voltage dividing resistor side. Configure.

In this case, when the power supply circuit on one side breaks down, when it is replaced and a new power supply circuit is connected, the charge of the output side smoothing capacitor in this power supply circuit is O, so the moment it is connected, the power supply circuit becomes overloaded due to the charge of this capacitor. This can lead to a load condition, which can cause the power supply to alarm and stop, or cause equipment malfunction due to a drop in supply voltage. To prevent this, an OR diode is inserted in one output line.

[Industrial Application Field] The present invention relates to a power supply circuit device with a diode OR circuit.

In general, communication equipment can be used without stopping the equipment.
Maintenance is required. For this reason, two or more power supplies are diode-OR connected to each other so that one of the power supplies that supplies power to the device can be replaced while the other remains in operation. That is, 2
Connecting the outputs of two power supply circuits in parallel to supply power to a load [Prior art] Fig. 3 is a block diagram of a conventional power supply circuit device with a diode OR circuit. 1 and 2 are power supply circuits, and these power supply circuits 1 and 2 are connected in parallel to a device (load) 3 such as a communication device.

Also, D#1. D#2 is an OR diode, and these O
R diode D#1. D#2 is the corresponding power supply circuit 2,
It is inserted into one output line to prevent backflow to 1.

Then, each OR diode D#1. An output voltage sense point is provided on the 7th node side of D#2 to monitor the output voltage V and (2) to maintain a constant output voltage v0.

That is, each OR diode D#1. Output voltage monitoring unit 1A of power supply circuits 1 and 2 from the anode side of D#2.

Output voltage information for feedback to 2A is extracted.

With this configuration, if one power supply circuit fails, even if it is replaced and a new power supply circuit is connected, the OR
Diode D#1. Due to the action of D#2, the smoothing capacitor on the output side in the power supply circuit is not charged, which prevents the power supply from stopping due to an alarm and from causing incorrect operation of the device due to a drop in the supply voltage. It has become.

[Problems to be Solved by the Invention] However, in the conventional power supply circuit device with a diode OR circuit shown in FIG. 3, the output voltage slightly decreases due to the voltage drops vF, vF2 caused by the OR diodes D#1 and D#2. Therefore, the output voltage value is set a little higher and the OR diode D#1. D#2 voltage drop V Fx* VFi
are offsetting.

However, OR diode D#1. The voltage drop vF, vF, of D#2 varies depending on the current flowing there, that is, the output current, so in a conventional power supply circuit device with a diode OR circuit as shown in Figure 3, the output voltage accuracy is poor. There is a problem with that.

Therefore, as shown in FIG. 4, the voltage sensing point is connected to the OR diode D#1. It is also possible to install it on the cathode side of D#2, but in this case, the voltage drop of the diode can be ignored, but if the two power supply circuits 1゜2 are connected with diode OR, the mutual output voltage value will be equal to the rated value. Since there is a slight difference within the range of error, the one with a slightly higher output voltage will supply power to the device (load) 3 side.

Here, power supply circuit 1 is a power supply circuit with a slightly higher output voltage, power supply circuit 2 is a power supply circuit with a slightly lower output voltage, and power supply circuit 1
Let the voltage drop across OR diode D#1 be vF, and let the output voltage on the anode side of OR diode D#1 be vl, and let the voltage drop across OR diode D#2 in power supply circuit 2 be VF2,
When the output voltage on the anode side of OR diode D#2 is v2 and the voltage supplied to the device (load) 3 is vo, the following equation holds true.

Vx VFl>Vi VFl ・” ' (1)
Va”Vi VFt ” ” ” (2)V
D>Vi VFl... (3) This (3)
From the formula, power supply circuit 2 is OR diode D#2, so
Unable to monitor its own output voltage v2V F 2, it mistakenly recognizes the output voltage v0 of power supply circuit 1 as its own output voltage, and according to equation (1), vo is higher than its own set output voltage value Vz VFz. attempts to lower the output voltage v2 of.

But no matter how much I reduce my output voltage.

Since the output voltage value v0 being monitored is kept constant by the power supply circuit 1, the power supply circuit 2 finally reaches V,=O
(See section 81 in Figure 5).

In this case, if the power supplied to the device (load) 3 takes into account the diode-OR connection, it is possible to supply power even with one power supply circuit 1, but if the power supply circuit 1 breaks down, as shown in Fig. 5. As indicated by b1, the device (load) 3 may malfunction while the output voltage of the power supply circuit 2 increases from V2=OV to the rated value and returns.

The present invention was made in view of these problems, and
In the case where the voltage sense point for monitoring the output voltage is provided on the cathode side of the OR diode, the output voltage of the power supply circuit whose output voltage is slightly lower is prevented from lowering further from a value slightly lower than the rated voltage. , an object of the present invention is to provide a power supply circuit device with a diode OR circuit.

[Means for Solving the Problems] For this reason, the power supply circuit device with a diode-OR circuit of the present invention has a function that prevents reverse current to the corresponding power supply circuit from each output side of a pair of power supply circuits connected in parallel to the load. In a power supply circuit device with a diode OR circuit that is equipped with an OR diode for protection, a voltage dividing resistor is connected to the anode side of each OR diode, and an output voltage monitoring section of the power supply circuit is connected to the cathode side of each OR diode. An output voltage divider resistor is connected to take out output voltage information for feedback to the output voltage divider, and the output voltage divider is connected between the voltage divider point of the voltage divider resistor and the voltage divider point of the output voltage divider resistor. It is characterized in that a diode is interposed to allow conduction from the piezoresistor side to the voltage dividing resistor side.

[Function] With the above-described configuration, in the power supply circuit device with a diode OR circuit of the present invention, the power supply circuit with a slightly lower output voltage,
A diode inserted between the voltage dividing point of the voltage dividing resistor and the voltage dividing point of the output voltage dividing resistor on the output side becomes conductive, thereby reducing the voltage dividing point of the output voltage dividing resistor. decreases. As a result, the output voltage does not fall further from a value slightly lower than the rated voltage.

[Example] The present invention will be described in detail below with reference to one drawing.

FIG. 1 is a block diagram showing an embodiment of the present invention. In this FIG. are connected in parallel.

Also, D#1. D#2 is an OR diode, and these O
R diode D#1. D#2 is the corresponding power supply circuit 2, 1
It is inserted in one of the output lines to prevent backflow.

Further, voltage dividing resistors R11, R12; R21, R22 are connected to the anode side of each OR diode D#1; D#2, and each OR diode D$tl;
On the cathode side of #2, output voltage dividing resistors R13, R141, R23, and R2 are provided to take out output voltage information for feedback to the output voltage monitoring unit 1A; 2A of the power supply circuit 1;
4 are connected.

Note that the power supply circuits 1 and 2 have their output voltage monitoring units 1A;
A monitors the output voltage from the voltage values divided by the resistors R13, R14; R23 and R24, and controls the output voltage to a constant value.

And these voltage dividing resistors R11, R12; R21,
Voltage dividing point Al of R22; A2 and output voltage dividing resistor R
13, R14; Between voltage dividing points Bl and B2 of R23, R24, output voltage dividing resistors R13, R14: R23,
From the R24 side, divider resistors R11, R12; R21, R2
Diodes D1 and D2 are interposed to allow conduction to the second side.

Note that the voltage dividing resistors R11, R12; R21, R22 and the output voltage dividing resistors R13, R14: R23, R24
The method for determining each value is as follows. First, resistor R1
3, R14; Determine the values of R23 and R24. Next, considering the diode drop, resistors R11, R12;
, R22 is determined. Then, in consideration of the combined resistance value when the diode is conductive, the values of the resistors R12 and R22 are determined, and further the values of the resistors R11 and R21 are determined.

With the above configuration, the output voltage of the power supply circuit 1 is set to vl,
The voltage drop of OR diode D#1 is VFz, the divided voltage value of resistors R13 and R14 is vR□, the output voltage of power supply circuit 2 is v2, the voltage drop of OR diode D#2 is VFx, Let the divided voltage value of resistors R23 and R24 be VB2, and further set v, -v, >v, -vF,
The power supply circuit 2 recognizes VRz, which is obtained by dividing the voltage value of V, =V□-vF, as an output voltage.

However, assuming that the voltage division value of resistors R21 and R22 is V'Rz, when Vo=Vz VFZ, V'R2≧VRz, and when v, vFz>v2-vp'z, V'R2< VR2 How about resistor R2
1° If R22, R23, and R24 are determined, V, VFt)
If v2-vl-2(7), then V'R2<VB2
Therefore, current iD flows through diode D2, and resistor R
22.degree.

In this state, even if the power supply circuit 1 fails and stops (see part b2 in Figure 2), the power supply circuit 2 is in a waiting state at a value slightly lower than the rated output voltage value (82 in Figure 2). (see section)
, the rated output voltage can be immediately supplied to the device (load) 3.

On the other hand, in the case of V, :V2 vF, v'R2≧VR
z, no current flows through the diode D2, and as a result, the output voltage is monitored by the voltage division ratio of the resistors R23 and R24, and the circuit operates in a normal state.

Note that when the output voltage of power supply circuit 1 is lower than that of power supply circuit 2, the power supply voltage 1 is
is set to a standby state with the output voltage slightly lower than the current output voltage value.

As described above, the power supply circuit device with a diode-OR circuit according to the present embodiment realizes a highly accurate output voltage for the power supply circuit having a diode-OR connection function, and solves the conventional problems described above. Therefore, it is possible to realize a power supply circuit device that can be maintained without power outage.

[Effects of the Invention] As detailed above, according to the power supply circuit device with a diode OR circuit of the present invention, in which the voltage sense point for monitoring the output voltage is provided on the cathode side of the OR diode, the output voltage Since the output voltage of the slightly lower power supply circuit will not be lowered from a value slightly lower than the rated voltage, it is possible to achieve a highly accurate output voltage, and furthermore, maintenance can be performed without interruption. There is an advantage that a power supply circuit device can be realized.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing output voltage characteristics in an embodiment of the present invention, FIG. 3 is a block diagram showing a conventional example, and FIG. 4 is a block diagram showing another example. FIG. 5 is a block diagram showing a conventional example, and is a diagram showing output voltage characteristics in the conventional example shown in FIG. In the figure, 1 and 2 are power supply circuits, 1A and 2A are output voltage monitoring units, 3 is a device (load), and Di1. Di2 is an OR diode, Di, D2 are diodes, R11, R12, R21, R22 are voltage dividing resistors, R13
, R13, R23, and R23 are output voltage dividing resistors. Power supply port %1/'l output main 9Fl+n-actual 7tLflll ;:bi76B power t/
LWtLLffiTtD Fig. 2 Alloc diagram showing conventional f1 7r XT70 link scheme conventional 91

Claims (1)

[Claims] A pair of power supply circuits (1) connected in parallel to a load (3).
;2) In a power supply circuit device with a diode OR circuit, each output side is equipped with an OR diode (D#1; D#2) that prevents backflow to the corresponding power supply circuit (2;1). On the anode side of the diode (D#1; D#2),
A voltage dividing resistor (R11, R12; R21, R22) is connected, and the cathode side of each OR diode (D#1; D#2) is
Output voltage dividing resistors (R13, R14; R23, R24) are connected to take out output voltage information for feedback to the output voltage monitoring unit (1A; 2A) of the power supply circuit (1; 2), and the voltage dividing resistor vessel (R11, R12; R21, R22
) voltage dividing point and the output voltage dividing resistor (R13, R14;
Conductivity is established from the output voltage dividing resistor (R13, R14; R23, R24) side to the voltage dividing resistor (R11, R12; R21, R22) side between the voltage dividing point of R23, R24). A power supply circuit device with a diode OR circuit, characterized in that a permissible diode (D1; D2) is interposed.