Utility model content
The utility model provides a kind of radio-frequency feed protection circuit, for solving prior art in carried out using integrated chip
Relatively costly during current-limiting protection, the loss of feed circuit is larger, and causes that peripheral circuit signal transmission matching is not good to ask
Topic.
The utility model embodiment provides a kind of radio-frequency feed protection circuit, including:
On-off circuit, first switch control circuit, second switch control circuit;
Second end of the on-off circuit is connected with voltage input end, the 3rd end and voltage output end and radio circuit phase
Even, the on-off circuit controls the on-off circuit according to the voltage of the on-off circuit first end for closure or openness shape
State, so as to control voltage input is to radio circuit output voltage;
The first end of the first switch control circuit is connected with the voltage output end, the first switch control circuit
The second end be connected with the first end of the on-off circuit, the first switch control circuit be used for it is short out according to the radio frequency electrical
The output voltage of voltage output end during road, controls the voltage of the on-off circuit first end to close the on-off circuit
Voltage, so as to closure switch circuit;
The second switch control circuit, is connected with the first end of the on-off circuit, the second switch control circuit
For in the radio circuit normal work, controlling the voltage of the on-off circuit first end to open the on-off circuit
Voltage, so as to open on-off circuit.
Further, the first switch control circuit include the first triode, the first end of first triode with
The voltage output end connection, the second end of first triode is connected with the voltage input end, first triode
The 3rd end be connected with the first end of the on-off circuit.
Further, the first switch control circuit also includes what is be sequentially connected in series from the voltage input end to earth terminal
First electric capacity, first resistor and second resistance, the first end of first triode be located at first electric capacity with described the
First node connection between one resistance, the voltage output end and between the first resistor and the second resistance
Section Point connects, so as to be connected with the first end of first triode by the first resistor.Further, described
One triode is p-type triode PNP, and the first end of first triode is the base stage of the PNP, first triode
Second end is the emitter stage of the PNP, and the 3rd end of first triode is the colelctor electrode of the PNP.Further, it is described
On-off circuit include switching transistor, the switching transistor be P-type mos PMOS, the on-off circuit
First end be the PMOS grid, the second end of the on-off circuit is the source electrode of the PMOS, switch electricity
3rd end on road is the drain electrode of the PMOS.Further, the on-off circuit also includes being located at the of the on-off circuit
3rd resistor in parallel and the second electric capacity between one end and the second end of the on-off circuit, second electric capacity is used for described
Discharged during voltage input end power down, the first end and the second end for the on-off circuit provides voltage, to the switch electricity
Road carries out buffer protection.
Further, the circuit also includes:
Control voltage input, is connected with the second switch control circuit, for the second switch control circuit
Input control voltage, so that the second switch control circuit can keep it turned on, and in the normal work of the radio circuit
When making, the voltage of the on-off circuit first end is controlled, so that the on-off circuit is opening.
Further, the second switch control circuit includes:Second triode, the first end of second triode with
The first end connection of the on-off circuit, the second end of second triode is connected with the control voltage input, described
The 3rd end ground connection of the second triode.
Further, the second switch control circuit also includes:Positioned at the control voltage input and described second
The 4th resistance between second end of triode, the 5th between the control voltage input and another earth terminal is electric
Resistance, the 6th resistance between the second triode first end and the first end of the on-off circuit.Further, it is described
Second triode is N-type triode NPN, and the base stage of the NPN is the second end of second triode, the current collection of the NPN
The first end of extremely described second triode, the 3rd end of extremely described second triode of transmitting of the NPN.
Further, the circuit also includes:
3rd electric capacity, between the input and rf access point of the radio circuit, wherein the rf access point
For the point that the on-off circuit is connected with radio circuit, for intercepting the input that DC voltage feeds back to the radio circuit
End.
Further, the circuit also includes:
Radio frequency bypass circuit, between the voltage output end and the radio circuit, for intercepting radio circuit in
High-frequency signal export in the on-off circuit.
In the utility model embodiment, controlled whether to radio circuit output voltage using on-off circuit, and utilize first
When radio circuit is short-circuited, controlling switch circuit is closure state to ON-OFF control circuit so that on-off circuit is no longer to penetrating
Frequency circuit output voltage, it is ensured that radio circuit will not cause to damage when being short-circuited to the device for connecting radio circuit output end
Evil;In the utility model embodiment, can effectively ensure that in radio circuit normal work using second switch control circuit
When, it is ensured that the state of on-off circuit is opening, i.e., to radio circuit output voltage.In the utility model embodiment, use
On-off circuit carries out feed circuit protection, and circuit cost is low, simple structure, and the matching of circuit is strong.
Specific embodiment
In order that the purpose of this utility model, technical scheme and advantage are clearer, below in conjunction with accompanying drawing to this practicality
It is new to be described in further detail, it is clear that described embodiment is only the utility model some embodiments, rather than
Whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making creative work
Under the premise of all other embodiment for being obtained, belong to the scope of the utility model protection.
The utility model provides a kind of radio-frequency feed protection circuit, as shown in figure 1, including:
On-off circuit 100, first switch control circuit 110, second switch control circuit 120;
Second end 1002 of the on-off circuit 100 is connected with voltage input end 130, and the 3rd of the on-off circuit 100 the
End 1003 is connected with voltage output end 140 and radio circuit 180, and the on-off circuit 100 is according to the on-off circuit 100
The voltage of first end 1001 controlling the state of the on-off circuit 100, so as to the output voltage of radio circuit 180;
The first end 1101 of the first switch control circuit 110 is connected with the voltage output end 130, and described first opens
The second end 1102 for closing control circuit 110 is connected with the first end 1001 of the on-off circuit 100, the first switch control electricity
Road 110 is used for the output voltage according to the voltage output end 140 when short-circuit of the radio circuit 180, the on-off circuit 100
First end 1001 voltage be make the on-off circuit 100 close voltage, so as to closure switch circuit 100;
The second switch control circuit 120, is connected with the first end 1001 of the on-off circuit 100, and described second opens
Closing control circuit 120 is used to control the first end 1001 of the on-off circuit 100 in 180 normal work of radio circuit
Voltage be make the on-off circuit 100 open voltage, so as to open on-off circuit 100.In the utility model embodiment,
The voltage of voltage input end 130 can be 28V, or for 12V.Voltage is passed through on-off circuit 100 by the voltage input end 130
To the output voltage of radio circuit 180, so as to be connected to the RF Components normal work of radio circuit output end 1801.
In the utility model embodiment, the state of on-off circuit 100 has two kinds, and one kind is closure state, that is, switch electricity
Road 100 is no longer to the output voltage of radio circuit 180;One kind is exported for opening, i.e. on-off circuit 100 to radio circuit 180
Voltage.
In the utility model embodiment, when radio circuit 180 is normal work, on-off circuit 100 is needed to open
State, on-off circuit 100 to the output voltage of radio circuit 180 so that the normal work of radio circuit 180.
In the utility model embodiment, the opening and closed mode of on-off circuit 100 are by on-off circuit 100
First end 1001 controlling, in the utility model embodiment, when 180 normal work of radio circuit, the of on-off circuit 100
The voltage of one end 1001 is controlled by second control circuit 120, makes on-off circuit 100 be in opening;Work as radio circuit
180 when being short-circuited, and the voltage of the first end 1001 of on-off circuit 100 is controlled by first switch control circuit 110,
On-off circuit 100 is set to be in closure state.
In the utility model embodiment, voltage output end 140 connects with the second end 1102 of first switch control circuit 110
Connect, when radio circuit 180 is short-circuited, the voltage in radio circuit 180 is undergone mutation, i.e., by the electricity of voltage input end 130
Pressure sports zero, and now the voltage of voltage output end 140 is equal with the voltage in radio circuit 180, i.e. vanishing, and now first
ON-OFF control circuit 110 it is determined that voltage output end 140 voltage vanishing when, it is determined that radio circuit 180 is short-circuited, then
By the voltage of the first port 1001 of the controlling switch circuit 100 of second port 1102 of first switch control circuit 110, so that
On-off circuit 100 is changed into closure state from opening, protects the RF component of the connection of radio circuit output end 1801.
In the utility model embodiment, as shown in Fig. 2 first switch control circuit 110 includes the first triode 1103,
The first end 110301 of the first triode 1103 is connected with voltage output end 140, the second end 110302 of the first triode 1103
It is connected with voltage input end 130, the 3rd end 110303 of the first triode is connected with the first end 1001 of on-off circuit 100.
Optionally, in the utility model embodiment, as shown in Fig. 2 in order to preferably represent first switch control electricity
Road 110 and the annexation of voltage output end 140, also set near the first triode 1103 of first switch control circuit 110
There is a voltage output end 140, connected with wire between two voltage output ends 140 in circuit.
Optionally, in the utility model embodiment, the first triode 1103 is p-type triode PNP, the first triode
1103 first end 110301 for PNP base stage, the second end 110302 of the first triode 1103 for PNP emitter stage, first
3rd end 110303 of triode 1103 is the colelctor electrode of PNP.
In the utility model embodiment, as shown in figure 3, first switch control circuit 110 is also included from voltage input end
The first electric capacity 1104, first resistor 1105 and second resistance 1106 that 130 to earth terminal is sequentially connected in series, first triode
1103 first end 110301 and the first node 11001 between the first electric capacity 1104 and first resistor 1105 connect, electricity
Pressure output end 140 and the Section Point between first resistor 1105 and second resistance 1,106 11002 connect, so as to pass through the
One resistance 1105 is connected with the first end 110301 of the first triode 1103.
In the utility model embodiment, second resistance 1106 prevents voltage output end to be directly grounded, and optionally, second is electric
The resistance value of resistance is 10K Europe, and the effect of first resistor 1105 is the resistance value by adjusting first resistor 1105, it is ensured that voltage is defeated
The magnitude of voltage for going out end 140 is equal with the magnitude of voltage of radio circuit 180, optionally, in the utility model embodiment, first resistor
1105 resistance value is 100K Europe.
In the utility model embodiment, the effect of the first electric capacity 1104 is, when 180 normal work of radio circuit, to make electricity
Pressure input 130 does not act on the first end 110301 of the first triode 1103, on the other hand, when voltage input end 130 occurs
Failure, i.e. when the input voltage of voltage input end 130 suddenly becomes zero, the first electric capacity 1104 can be made in circuit by electric discharge
Voltage is slowly reduced to zero, the components and parts in protection circuit.
Optionally, in the utility model embodiment, the capacitance of the first electric capacity 1104 is 1 μ F, the first electric capacity 1104
It is pressure for 50V.
In the utility model embodiment, when 180 normal work of radio circuit, due to the effect of the first electric capacity 1104,
The voltage of the emitter stage 110302 of PNP pipe 1103 for voltage input end 130 voltage, the electricity of the base stage 110301 of PNP pipe 1103
Press as the voltage of voltage output end 140, due in 180 normal work of radio circuit, the voltage and voltage of voltage input end 130
The voltage of output end 140 is equal, so PNP pipe 1103 is not turned on.
When radio circuit 180 is short-circuited, the voltage vanishing of voltage output end 140, the base stage of PNP pipe 1103
Form voltage difference between 110301 and the emitter stage 110302 of PNP pipe 1103, and the emitter stage 110302 of PNP pipe 1103 with
The voltage difference of the base stage 110301 of PNP pipe 1103 is more than conducting electrical potential difference, so PNP pipe 1103 can be turned on, due to PNP pipe
After 1103 are turned on, the colelctor electrode 110303 of PNP pipe 1103 is connected with the first end 1001 of on-off circuit 100, it is possible to
Change the voltage of the first end 1001 of on-off circuit 100, so as to closing switch circuit 100.
In the utility model embodiment, as shown in figure 4, on-off circuit 100 includes switching transistor 101, the switch
Transistor 101 is P-type mos PMOS 101, and the first end 1001 of the on-off circuit 100 is the PMOS
The grid of pipe 101, the second end 1002 of the on-off circuit 100 for the PMOS 101 source electrode, the on-off circuit 100
The 3rd end 1003 for the PMOS 101 drain electrode.
In the utility model embodiment, the condition of the conducting of PMOS 101 is the voltage of the grid 1001 of PMOS 101
Less than the source electrode 1002 of PMOS 101, and the potential of the grid 1001 with PMOS 101 of the source electrode 1002 of PMOS 101
Difference is more than conducting electrical potential difference.In the utility model embodiment, in 180 normal work of radio circuit, the grid of PMOS 101
1001 voltage provides voltage by second switch control circuit 120, and the voltage of the source electrode 1002 of PMOS 101 is voltage input end
130 voltage, when voltage input end 130 voltage higher than second switch control circuit 120 voltage, and voltage input end
130 with the voltage difference of second switch control circuit 120 more than conducting electrical potential difference when, PMOS conducting, it is possible to radio circuit
180 output voltages.
When radio circuit 180 is short-circuited, as shown in Figure 3, Figure 4, the one or three pole in first switch control circuit 110
After switch, the grid voltage of PMOS 101 changes pipe 1103, and the voltage of the grid 1001 of PMOS 101 is that voltage is defeated
Enter the voltage at end 130, the voltage of the source electrode 1002 of PMOS 101 is the voltage of voltage input end 130, so PMOS is closed,
No longer to the output voltage of radio circuit 180.
In the utility model embodiment, on-off circuit 100 also includes being located at the first end 1001 of on-off circuit 100 and opens
The electric capacity 103 of 3rd resistor 102 and second in parallel between second end 1002 on powered-down road 100, the second electric capacity 103 is used in voltage
Discharged during 130 power down of input, be that 1001 and second end of first end 1002 of on-off circuit 100 provides voltage, to switch
Circuit 100 carries out buffer protection.
In the utility model embodiment, the effect of 3rd resistor 102 is, in 180 normal work of radio circuit, to reduce
By the electric current of 3rd resistor 102, so that the voltage of the voltage at the second end 1002 of on-off circuit 100 and voltage input end 130
Equal, optionally, in the utility model embodiment, the resistance value of 3rd resistor 102 is 100K Europe.
In the utility model embodiment, the effect of the second electric capacity 103 is, in 130 power down of voltage input end, to sponge
The spike formed when electric, reduces the impact of the switching transistor 101 to on-off circuit 100, protects transistor 101.
In the utility model embodiment, as shown in figure 5, the circuit also includes:Control voltage input 150, with
Two ON-OFF control circuits 120 connect, for being input into control voltage to second switch control circuit 120, so that second switch control
Circuit 120 can keep it turned on, and in 180 normal work of radio circuit, the first end 1001 of controlling switch circuit 100
Voltage, so that the on-off circuit 100 is opening.
In the utility model embodiment, the voltage of control voltage input 150 can be 3.3V and following, so that connection
Low-voltage in CPU can be turned on second switch control circuit 120.
In the utility model embodiment, as shown in fig. 6, second switch control circuit 120 includes:Second triode
1201, the first end 120101 of the second triode 1201 is connected with the first end 1001 of on-off circuit 100, the second triode 1201
The second end 120102 be connected with control voltage input 150, the 3rd end 120103 of second triode 1201 is grounded.
In the utility model embodiment, the second triode 1201 is used in 180 normal work of radio circuit, by leading
Logical second triode 1201, and then on-off circuit 100 is turned on, so that on-off circuit 100 transmits voltage to radio circuit 100.
In the utility model embodiment, optionally, the second triode 1201 is N-type triode NPN1201, NPN1201
Base stage be second triode 1201 the second end 120102, the of current collection extremely second triode 1201 of NPN1201
One end 120101, the 3rd end 120103 of transmitting extremely second triode 1201 of NPN1201.In the utility model embodiment
In, the condition of NPN1201 conductings is emitter stage 120103 of the voltage of the base stage 120102 of NPN1201 higher than NPN1201, because
The emitter stage 120103 of NPN1201 is grounded, as long as so conducting of the voltage of the base stage 120101 of NPN1201 higher than NPN1201
Electrical potential difference can realize the conducting of NPN1201.
In the utility model embodiment, as shown in fig. 7, second switch control circuit 120 also includes:Positioned at control voltage
The 4th resistance 1202 between input 150 and the second end 120102 of second triode 1201, it is defeated positioned at control voltage
Enter the 5th resistance between 150 another earth terminal different from the earth terminal at the 3rd end 120103 of the second triode 1201 of end
1203, the 6th between the first end 1001 and the first end 120101 of second triode 1201 of on-off circuit 100 is electric
Resistance 1204.
In the utility model embodiment, the effect of the 5th resistance 1203 is to form loop with control voltage input 150,
4th resistance 1202 is a biasing resistor, when the second 1201 normal work of triode, it is necessary to assure the second triode 1201
Emitter junction positively biased, collector junction it is reverse-biased.Bias current can be provided for the second triode 1201 using the 4th resistance 1202, make the
Two triodes 1201 are turned on.
In the utility model embodiment, the 6th resistance 1204 between the triode 1201 of on-off circuit 100 and second
Effect is pull down resistor, it is ensured that the first end 1001 of on-off circuit 100 is obtained in that electrical potential difference, it is ensured that on-off circuit 100 is led
It is logical.
Optionally, in the utility model embodiment, the resistance of the 4th resistance 1202 is 1K Europe, the resistance of the 5th resistance 1203
It is worth for 1K Europe, the resistance of the 6th resistance 1204 is 2K Europe.
In the utility model embodiment, as shown in figure 8, the circuit also includes:Also include the 3rd electric capacity 170, be located at
Between the input 1802 and rf access point 190 of the radio circuit 180, wherein rf access point 190 is on-off circuit 100
The point being connected with radio circuit 180, optionally, in the utility model embodiment, the 3rd end 1003 of on-off circuit 100 with
The access point of radio circuit 180 is 190, and the 3rd electric capacity 170 feeds back to penetrating for the radio circuit 180 for intercepting DC voltage
Frequency circuit input 1802.
Optionally, in the utility model embodiment, the capacitance of the 3rd electric capacity 170 is 1 μ F, the 3rd electric capacity it is pressure
For 100V.
In the utility model embodiment, as shown in figure 9, the circuit also includes radio frequency bypass circuit 160, positioned at voltage
Between output end 140 and radio circuit 180, for intercepting the high-frequency signal access switch circuit 100 of radio circuit 180.
In the utility model embodiment, the generation of radio circuit input 1802 of radio circuit 180 is high-frequency signal,
And be that the signal produced using voltage input end 130 provides radio circuit 180 voltage in on-off circuit 100, due to voltage
The DC voltage of the input of input 130, so the generation of voltage input end 130 is low frequency signal, so needing radio frequency bypass electricity
Road 160 is intercepted in the high-frequency signal access switch circuit 100 in radio circuit 180, it is ensured that the normal operation of on-off circuit 100.
Optionally, in the utility model embodiment, as shown in Figure 10, radio frequency bypass circuit 160 also includes inductance 1601
And the 4th electric capacity 1602, the effect of inductance 1601 is to intercept the high-frequency signal access switch circuit 100 in radio circuit 180,
The effect of the 4th electric capacity 1602 is to reduce power supply output ripple, and absorbs the switching frequency signal of on-off circuit 100.
Optionally, in the utility model embodiment, model CL6130-AL of inductance 1601, the 4th electric capacity 1602
Capacitance be 0.01 μ F, the 4th electric capacity 1602 it is pressure for 50V.
In the utility model embodiment, there is provided a kind of radio-frequency feed protection circuit, as shown in figure 11, including control source
End, voltage output end, on-off circuit, first switch control circuit, second switch control circuit, radio frequency bypass circuit, control electricity
Pressure input and the 6th resistance, the 3rd electric capacity composition.Wherein, first switch control circuit by the first electric capacity, first resistor,
Two resistance and PNP triode are constituted;On-off circuit is made up of the second electric capacity, 3rd resistor and PMOS;Radio frequency bypass electricity
Route inductance and the 4th electric capacity composition;Second switch control circuit is made up of the 4th resistance, NPN triode and the 5th resistance.
The base stage of PNP triode is located between the first electric capacity and first resistor, and voltage output end is located at second resistance and the
Between one resistance, the emitter stage of PNP triode is connected with voltage input end, the colelctor electrode of PNP triode and the grid of PMOS
Connection.
First electric capacity one end is connected with voltage input end, and the other end is connected with the base stage of PNP triode, and the one of first resistor
End is connected with the base stage of PNP triode, and the other end is connected with voltage output end, and one end and the voltage output end of second resistance connect
Connect, other end ground connection.
The grid of PMOS is also connected with the 6th resistance, and the source class of PMOS is connected with voltage input end, the leakage of PMOS
Pole is connected with voltage output end.Second electric capacity and 3rd resistor are connected in parallel between the emitter and collector of PNP triode.
The base stage of NPN triode is connected with control voltage input, connects between the base stage and control voltage input of NPN
4th circuit, the grounded emitter of NPN triode, the colelctor electrode of NPN triode is connected with the grid of PMOS, and connects
6th resistance.One end of 5th resistance is connected with control voltage input, and the other end is connected with another earth terminal, i.e., the 5th is electric
Resistance is between the control voltage input earth terminal different from the emitter stage of NPN.
Also connect between radio circuit input and the access point on radio frequency bypass circuit the 3rd electric capacity.Radio circuit with
Connect between voltage output end inductance, the 4th electric capacity has been connected between voltage output end and earth terminal.
Although having been described for preferred embodiment of the present utility model, those skilled in the art once know substantially
Creative concept, then can make other change and modification to these embodiments.So, claims are intended to be construed to bag
Include preferred embodiment and fall into having altered and changing for the utility model scope.
Obviously, those skilled in the art can carry out various changes and modification without deviating from this practicality to the utility model
New spirit and scope.So, if it is of the present utility model these modification and modification belong to the utility model claim and
Within the scope of its equivalent technologies, then the utility model is also intended to comprising these changes and modification.