CN2869948Y

CN2869948Y - Self protective voltage switch-over circuit

Info

Publication number: CN2869948Y
Application number: CN 200520147148
Authority: CN
Inventors: 赵骐; 陈玄同; 刘文涵
Original assignee: Inventec Corp
Current assignee: Inventec Corp
Priority date: 2005-12-29
Filing date: 2005-12-29
Publication date: 2007-02-14
Anticipated expiration: 2015-12-29

Abstract

This utility model discloses a switching circuit for self-protective voltage. The circuit operates the transfer of power switch for output of a few different voltage values via the control signal for voltage switching resulting from the encoder. When the power switch outputs incorrect voltage value, the circuit disables the output of incorrect voltage after comparison and judgment and by providing relevant information to the protective switch. With the present technology, fault switching may lead to fault, causing error in the output voltage value so that the subsequent operating circuit does not work normally or even becomes burnt. In case of abnormality in the output operating voltage, the switching circuit for self-protective voltage in this utility model detects the problem in time and informs the protective switch to disconnect the circuit, thus avoiding damage to the electronic device or equipment at the voltage output terminal and improving the safety of the switching circuit for voltage.

Description

The self-protection voltage commutation circuit

Technical field

This is novel to relate to a kind of voltage commutation circuit, relates in particular to a kind of voltage commutation circuit that has automatic protection functions when supply voltage switches.

Background technology

In a plurality of fields such as automatic controls, often need to provide the power supply of multiple operational voltage value at present.During such as the chip of the multiple model of burning, will need several magnitudes of voltage.Voltage commutation circuit just can provide different operational voltage value for different chips.

Common voltage commutation circuit is designed to: after the control signal control circuit switched, the magnitude of voltage of switching was directly exported, and powers to chip as operating voltage.

As shown in fig. 1, the voltage commutation circuit of existing method comprises: voltage source input socket, code translator and power switch.

The voltage source input socket provides multiple for the magnitude of voltage that switches for power switch, simultaneously send voltage switch logic signal to code translator, and change out the correspondent voltage switch-over control signal by code translator, the manipulation power switch switches, and powers with direct output after selecting to switch to the correspondent voltage value.

Yet this way of prior art still has many defectives, particularly various faults may occur when some fortuitous events occurring.Such as aging malfunctioning, the energization pins short-circuit between conductors of relay, cause making and to be loaded incorrect voltage in working chip under the lower voltage environment.If the operational voltage value that loads is lower, then chip can't operate as normal; If loaded higher operational voltage value, consequence will be very serious so, can cause the permanent damage of chip.

In addition, if the chip on the employing direct mode burning motherboard when having loaded higher voltage value, even may burn motherboard, cause great loss.

In fact, in a lot of circuit design, all can run into the problem that multiple voltage is switched.Especially in large scale circuit, when needing multiple voltage frequently to switch, commutation circuit just is more prone to break down, and the consequence that the voltage switch failure causes may be very serious, so be necessary circuit is improved.

Therefore, even if how can make because after the voltage change action generation that device failure or other fortuitous event lead to errors, circuit still can stop wrong voltage to be output effectively, thereby effectively avoid because device and the device damage that the supply voltage mistake causes becomes problem demanding prompt solution in the industry with the reliability of improving circuit.

The utility model content

This novel technical matters to be solved is to provide a kind of self-protection voltage commutation circuit; traditional voltage commutation circuit is improved; it partly is added with partly circuit in voltage output; after the affirmation operating voltage is normal,, guarantee that voltage commutation circuit can provide the operational voltage value of safety and precise just as final operating voltage output.

This novel a kind of self-protection voltage commutation circuit comprises: voltage source input socket, code translator and power switch.Wherein the voltage source input socket provides multiple for the magnitude of voltage that switches for power switch, code translator is electrically connected with voltage source input socket and power switch, and the voltage switch logic conversion of signals that the voltage source input socket sends sent to power switch for the voltage switch-over control signal, handle power switch and switch, power with direct output after selecting to switch to the correspondent voltage value.

In addition, this novel a kind of self-protection voltage commutation circuit increases partly circuit in the power switch back, comprise comparator module, decision circuitry and protection switch.At first the operational voltage value with power switch output feeds back to comparator module, the switchable voltage value operational voltage value of power switch output is real-time and the output of voltage source input socket compares in comparator module, and obtains a voltage status logical value; Again the voltage status logical value is delivered to decision circuitry from comparator module output; the voltage status logical value of voltage switch logic signal value that decision circuitry is sent the voltage source input socket and comparer output is carried out logical operation; whether normal with the real work magnitude of voltage of judging power switch output; and the protection switch that is positioned at according to judged result control on the voltage output channel of power switch connects or disconnects, and offers subsequent conditioning circuit and uses when the actual output of having only power switch just often just is allowed to output.

In sum, this novel advantage is:

This novel hardware circuit that utilizes is monitored the operational voltage value from power switch; when the operational voltage value of power switch output takes place when unusual; by relatively and decision circuitry in time know and take corresponding measure; disconnect as the pilot protection switch; thereby guarantee only to provide normal operational voltage value; and wrong voltage can not be output, and has improved the security of circuit.

Below in conjunction with the drawings and specific embodiments the utility model is described in detail, but not as to qualification of the present utility model.

Description of drawings

Fig. 1 is the structure calcspar of the voltage commutation circuit of prior art;

Fig. 2 is the structure calcspar of this novel a kind of self-protection voltage commutation circuit; And

Fig. 3 is the self-protection voltage commutation circuit structure calcspar of this novel embodiment.

Wherein, Reference numeral:

10: the voltage source input socket

20: code translator

30: power switch

40: comparator module

The 41:12V voltage comparator

The 42:5V voltage comparator

The 43:3V voltage comparator

50: decision circuitry

60: protection switch

Embodiment

Below, will elaborate to this novel better embodiment in conjunction with graphic part.

As shown in Figure 1, represented the voltage commutation circuit of prior art among the figure, this circuit comprises: voltage source input socket 10, code translator 20 and power switch 30.

Voltage source input socket 10 provides voltage switch logic signal for code translator 20 simultaneously for power switch 30 provides multiple for the magnitude of voltage that switches.Code translator 20 is electrically connected with voltage source input socket 10 and power switch 30, the correspondent voltage switch-over control signal is sent in code translator 20 conversions, handle power switch 30 and switch,, be directly output as subsequent conditioning circuit then and power to select the switching to correspondent voltage value.

As shown in Figure 2, represented a kind of self-protection voltage commutation circuit that this is novel among the figure, this circuit comprises: voltage source input socket 10, code translator 20, power switch 30, comparator module 40, decision circuitry 50 and protection switch 60.

Voltage source input socket 10 provides multiple for the magnitude of voltage that switches for power switch 30, provides voltage switch logic signal for code translator 20 and decision circuitry 50 simultaneously; Code translator 20 is electrically connected with voltage source input socket 10 and power switch 30, and the voltage switch logic conversion of signals that voltage source input socket 10 is sent is the voltage switch-over control signal, handles power switch 30; Power switch 30 switches the correspondent voltage value according to the voltage switch-over control signal, magnitude of voltage is offered protection switch 60, and feed back to comparator module 40; Comparator module 40 compares the operational voltage value and the switchable voltage value of power switch output, and the voltage status logical value is offered decision circuitry 50; The voltage switch logic signal value that voltage status logical value that decision circuitry 50 obtains comparator module 40 and voltage source input socket 10 send carries out logical operation, the break-make of pilot protection switch 60; Protection switch 60 is controlled it by decision circuitry and is connected or disconnected, and guarantees that the operational voltage value of output is normal.

Wherein decision circuitry 50 adopts programmable logic device (PLD); and use higher-order logic representation language (Advanced Boolean Expression Language; ABEL) as hardware description language; the voltage status logical value of voltage switch logic signal value and comparator module 40 outputs is carried out logical calculated; whether the magnitude of voltage of judging this moment according to result of calculation is normal, thus the break-make of decision protection switch 60.

This self-protection voltage commutation circuit is through relatively judging, can whether determine output voltage values according to actual conditions.When the real work magnitude of voltage of power switch 30 output just often, decision circuitry 50 control protection switches 60 are connected, otherwise decision circuitry 50 control protection switches 60 disconnect.

As shown in Figure 3, the self-protection voltage commutation circuit structure calcspar of having represented the embodiment that this is novel among the figure.

In the present embodiment, can three kinds of 12V/5V/3V be arranged, provide to power switch 30 by voltage source input socket 10 for the magnitude of voltage that switches.Because code translator 20 needs three voltage switch-over control signal lines of output, then code translator 20 needs two input ends at least, so code translator 20 selects for use a slice 2-4 code translator to get final product.If large scale circuit need switch at more kinds of voltage, then select the more code translator of door number according to actual conditions, perhaps use the code translator combinational circuit.

The 2-4 code translator can be deciphered two input states, obtains four output states.Voltage source input socket 10 produces three decoding output control signals, as the voltage switch-over control signal of handling power switch 30 for two selecting sides of code translator 20 provide two voltage switch logic signals.

Power switch 30 switches with decision to select which kind of magnitude of voltage according to the control signal of 2-4 code translator output, and this moment, the operational voltage value of output was not the operational voltage value of final use, but offered comparator module 40 earlier.

Comparator module 40 includes three comparers in the present embodiment, is respectively 12V voltage comparator 41,5V voltage comparator 42 and 3V voltage comparator 43.

Wherein the comparer in the comparator module 40 is all selected 40 common series of comparisons devices for use, withstand voltage at 15V with the interior requirement of promptly satisfying present embodiment.Under concrete condition, can select the higher device of withstand voltage for use according to different voltage requirements.

Two input ends of each comparer, the operational voltage value of a termination power switch 30 outputs, the switchable voltage value of a termination voltage source input socket 10 outputs promptly is respectively 12V, 5V or 3V magnitude of voltage.

Through relatively, if the operational voltage value of power switch 30 outputs is higher than the switchable voltage value, then export high level, on the contrary output low level then, the output of comparator module 40 just can obtain a voltage status logical value like this.

Among this embodiment, if the operational voltage value of power switch 30 outputs is higher than 12V, then the output logic value of comparator module 40 is 111; If the operational voltage value of power switch 30 outputs is 12V, then the output logic value of comparator module 40 is 011; If the operational voltage value of power switch 30 outputs is 5V, then the output logic value of comparator module 40 is 001; If the operational voltage value of power switch 30 outputs is 3V, then the output logic value of comparator module 40 is 000.This logical value is as the input of decision circuitry, for next step processing.

But decision circuitry 50 can be selected programmable logic device (PLD) for use, as belongs to array logic (GAL) together device or program array logic (PAL) device, because the programmable logic device (PLD) size is little, power consumption is low, lead time is short, and Change In Design is convenient, and total cost of development is very low.Programmable logic device (PLD) adopts advanced logical expressions language (ABEL) to write, and advanced logical expressions language (ABEL) is grasped than being easier to as a kind of general hardware descriptive language, uses very extensive at present in programmable logic device (PLD).This is novel not limited thereto, also can adopt other suitable device or language.

The effect of decision circuitry 50 is that the voltage status logical value of comparator module 40 output is carried out the logical operation processing with the voltage switch logic signal that voltage source input socket 10 provides.

For example; voltage switch logic signal controlling output 12V voltage; then its logical value is 11; when if the actual output voltage of power switch 30 is higher than 12V; Volcomp12# is high; Output obtains high level according to logical operation, and protection switch disconnects, and the self-protection voltage commutation circuit plays a protective role.

If voltage switch logic signal controlling output voltage is 12V, the actual output voltage of power switch 30 is higher than 12V, and this moment, the logic state of decision circuitry was as follows.Powerctrl 1# is high, and Powerctrl2# is high, and Volcomp12# is high, and Output is high according to logic operation result.

If voltage switch logic signal controlling output voltage is 12V, the actual output voltage of power switch 30 is not higher than 12V, and this moment, the logic state of decision circuitry was as follows.Powerctrl 1# is high, and Powerctrl2# is high, and Volcomp12# is Low, and Output is Low according to logic operation result.

Similarly can write out the logic state of other situation, repeat no more herein.According to above-mentioned logic state, use advanced logical expressions language (ABEL) to write the device logic, obtain the logical consequence of decision circuitry, the control protection switch.

Protection switch 60 selects for use common relay directly to control in the present embodiment, can select suitable device for use according to the voltage requirements under the actual conditions in addition, relay or other voltage control device higher as withstand voltage.

Protection switch 60 is positioned on the voltage output channel of power switch 30, is subjected to decision circuitry 50 control break-makes, and the output of protection switch 60 is exported the result for using as final power supply.The operating voltage of explanation power switch 30 outputs is higher than the switchable voltage value during decision circuitry 50 output high level, and for the operating voltage that guarantees power supply output is normal, protection switch 60 can disconnect, and this self-protection voltage commutation circuit plays useful effect.

In the self-protection voltage commutation circuit,, have only operational voltage value just often by comparing and judging; magnitude of voltage is output smoothly; offer subsequent conditioning circuit and use, abnormal operating voltage is forbidden output, thereby can avoid consequences such as circuit cisco unity malfunction and chip are burnt.

Certainly; the utility model also can have other various embodiments; under the situation that does not deviate from the utility model spirit and essence thereof; those of ordinary skill in the art work as can make various corresponding changes and distortion according to the utility model, but these corresponding changes and distortion all should belong to the protection domain of the appended claim of the utility model.

Claims

1; a kind of self-protection voltage commutation circuit; comprise a voltage source input socket; one power switch and a code translator; this voltage source input socket provides the voltage of multiple voltage value to export this power switch to; this code translator is electrically connected with this voltage source input socket and this power switch; and the voltage switch logic conversion of signals that this voltage source input socket sends sent to this power switch for the voltage switch-over control signal; controlling this power switch switches; to export the operational voltage value of different magnitudes of voltage; it is characterized in that the self-protection voltage commutation circuit further comprises:

One comparator module is electrically connected with the output terminal of this voltage source input socket and the output terminal of this power switch;

One decision circuitry is electrically connected with the output terminal of this comparator module and the output terminal of this voltage source input socket; And

One protection switch, this protection switch are positioned on the voltage output channel of this power switch and with this decision circuitry and are electrically connected.

2, self-protection voltage commutation circuit according to claim 1 is characterized in that, this protection switch is a relay or other voltage control device.

3, self-protection voltage commutation circuit according to claim 1 is characterized in that, this decision circuitry is a programmable logic device (PLD).

4, self-protection voltage commutation circuit according to claim 1 is characterized in that, this comparator module comprises a plurality of comparers of respectively corresponding multiple different magnitudes of voltage.

5, self-protection voltage commutation circuit according to claim 3 is characterized in that, this programmable logic device (PLD) adopts general array logic or array logic chip able to programme.