A detection circuit and method for a firing current

Abstract

The application provides a detection circuit and method of firing current, which can realize accurate collection of firing current, is convenient to operate and has high measurement precision; the detection circuit and method comprise a detonation current sampling module, a comparison module and a trigger module; the comparison module is connected with the detonation current sampling module and is used for judging whether there is firing current; the trigger module is connected with the detonation current sampling module and the comparison module and is used for receiving an output signal of the comparison module and sending a level trigger signal to the detonation current sampling module; the detonation current sampling module comprises a current sampling unit, which is connected with the firing loop and the comparison module, is used for sampling input current and sends a current signal to the comparison module; and a sampling holding unit, which is connected with the current sampling unit and the trigger module, is used for sampling and storing input current according to the level trigger signal and keeping current peak value output.

Description

Technical Field

[0001] This invention relates to the field of electronic detonator control module testing technology, specifically a detection circuit and method for ignition current. Background Technology

[0002] With the increasingly widespread application of electronic detonators, it is necessary to test the functional parameters of the electronic detonator delay control module. During the testing process, various parameters of the electronic detonator module need to be measured. Among these, the ignition current represents the ignition capability. When current flows, the ignition resistor will spark or heat up. The outer layer of the ignition resistor is coated with a propellant, which ignites the propellant in the electronic detonator through the propellant in the detonator head. A higher current results in a stronger ignition capability and a easier detonation. Therefore, the ignition current is crucial to whether the propellant head can be detonated. However, existing equipment lacks data acquisition and analysis of the ignition current. Issues such as poor contact or unstable voltage can cause changes in the ignition current, making it impossible to accurately obtain peak ignition current data. This hinders the statistical analysis and tracking of production data for the electronic detonator control module, leading to low production efficiency and hindering product upgrades and modifications. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides a detection circuit and method for ignition current, which can accurately acquire ignition current, is easy to operate, and has high measurement accuracy.

[0004] The technical solution of the present invention is as follows: an ignition current detection circuit, comprising an ignition current sampling module, a comparison module, and a triggering module;

[0005] The comparison module is connected to the detonation current sampling module and is used to determine whether there is an ignition current.

[0006] The triggering module is connected to both the detonation current sampling module and the comparison module, and is used to receive the output signal of the comparison module and send a level trigger signal to the detonation current sampling module.

[0007] The detonation current sampling module includes:

[0008] The current sampling unit is connected to both the ignition circuit and the comparison module. It is used to sample the input current and send the current signal to the comparison module.

[0009] The sample-and-hold unit is connected to both the current sampling unit and the trigger module. It is used to sample and register the input current according to the level trigger signal and hold the peak current output.

[0010] Furthermore, the detection circuit also includes a compensation module, which is connected to the current sampling unit and is used to compensate for the offset voltage of the current sampling unit.

[0011] Furthermore, the detection circuit also includes a current output module, which is connected to both the current sampling unit and the control module, and is used to output the sampled input current to the control module; the control module includes a microcontroller to collect instantaneous current information and perform signal processing.

[0012] Further, the detonation current sampling module includes resistors R1-R7, capacitors C1-C7, a Schottky diode D1, a current sensor U1, an operational amplifier U2, and a sample-and-hold circuit U3. One end of resistor R1 is connected to the output terminal of the ignition circuit, and the other end of resistor R1 is connected to pins 1 and 2 of the current sensor U1. One end of capacitor C1 is connected to pin 8 of the current sensor U1 and then connected to a 3.3V power supply; the other end of capacitor C1 is grounded. One end of capacitor C2 is connected to pin 5 of the current sensor U1 and then grounded; the other end of capacitor C2 is connected to pin 6 of the current sensor U1. Pin 7 of the current sensor U1 is connected to one end of capacitor C3 and one end of resistor R2. The other end of resistor R2 is connected to one end of resistor R3 and pin 3 of operational amplifier U2. Pin 2 of operational amplifier U2 is connected to one end of resistors R4 and R5. The other end of resistor R4 is grounded. The other end of resistor R5 is connected to pin 1 of operational amplifier U2 and pin 1 of Schottky diode D1. Pin 2 of Schottky diode D1, pin 3 of Schottky diode D1, and one end of resistor R6 are all connected. The other end of resistor R6 is connected to one end of capacitor C4 and pin 3 of sample-and-hold circuit U3. The other end of capacitor C4 is grounded. One end of capacitor C7 is connected to pin 7 of sample-and-hold circuit U3 and then grounded. The other end of capacitor C7 is connected to pin 6 of sample-and-hold circuit U3. One end of capacitor C5 is connected to pin 1 of sample-and-hold circuit U3 and then connected to a 12V power supply. The other end of capacitor C5 is grounded. One end of capacitor C6 is connected to pin 4 of sample-and-hold circuit U3 and then connected to a -12V power supply. The other end of capacitor C6 is grounded. One end of resistor R7 is connected to pin 5 of sample-and-hold circuit U3.

[0013] Further, the comparison module includes resistors R8 to R11, capacitor C8, and comparator U4; one end of resistor R8 is connected to pin 4 of comparator U4, and the other end of resistor R8 is connected to a 3.3V power supply; pin 1 of comparator U4 is connected to pin 3 of sample-and-hold circuit U3; pin 3 of comparator U4 is connected to one end of resistors R9 and R10; the other end of resistor R9 is connected to the 3.3V power supply; the other end of resistor R10 is connected to one end of resistor R11; the other end of resistor R11 is grounded; one end of capacitor C8 is connected to pin 5 of comparator U4 and then connected to a 5V power supply; the other end of capacitor C8 is connected to pin 2 of comparator U4 and then grounded.

[0014] Furthermore, the trigger module includes a resistor R12, capacitors C9 and C10, and a D flip-flop U5; pin 1 of the D flip-flop U5 is connected to pin 4 of the comparator U4, pin 2 of the D flip-flop U5 is connected to a 3.3V power supply, pin 4 of the D flip-flop U5 is grounded, one end of the resistor R12 is connected to pin 3 of the D flip-flop U5, pin 8 of the comparator U4 is connected to the other end of the resistor R12 and one end of the capacitor C9, one end of the capacitor C10 is connected to pins 7 and 8 of the D flip-flop U5 and then connected to the 3.3V power supply, and the other end of the capacitor C10 is grounded;

[0015] Furthermore, the compensation module includes resistors R13 to R15, capacitor C11, and operational amplifier U6; pin 5 of operational amplifier U6 is connected to one end of resistors R13 and R14, the other end of resistor R13 is connected to a 3.3V power supply, pins 6 and 7 of operational amplifier U6 are connected to the other end of resistor R3, the other end of resistor R14 is connected to one end of resistor R15, the other end of resistor R15 is connected to one end of capacitor C11 and pin 4 of operational amplifier U6 and then grounded, the other end of capacitor C11 is connected to a 3.3V power supply;

[0016] Furthermore, the current output module includes a capacitor C12 and a voltage follower U7; pin 3 of the voltage follower U7 is connected to pin 7 of the current sensor U1, pins 1 and 4 of the voltage follower U7 are connected to the output terminal of the ignition circuit, one end of the capacitor C12 is connected to pin 5 of the voltage follower U7 and then connected to a 3.3V power supply, and the other end of the capacitor C12 is connected to pin 2 of the voltage follower U7 and then grounded;

[0017] This invention also proposes a method for detecting ignition current, comprising the following steps:

[0018] The input signal is sampled at the output of the self-ignition circuit.

[0019] Determine whether there is current input based on the sampled input signal;

[0020] If there is current input, the trigger module sends a high-level signal to the sample and hold unit to sample and register the input ignition current and hold the peak current output.

[0021] If there is no current input, the trigger module sends a low-level signal to the sample-and-hold unit and outputs the signal in response to the input signal.

[0022] The beneficial effects of this invention are that it can quickly sample the detonation current, determine whether detonation has occurred by judging whether there is current input, and then drive the trigger module to maintain a stable level to the sampling and holding unit to hold the current peak value and obtain the maximum value of the ignition current, thereby achieving accurate acquisition of the ignition current with high measurement accuracy and good economic value. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] Figure 2 This is a circuit diagram of the detonation current sampling module in this invention;

[0025] Figure 3 This is the circuit schematic of the comparison module in this invention;

[0026] Figure 4 This is the circuit schematic diagram of the trigger module in this invention;

[0027] Figure 5 This is the circuit schematic diagram of the compensation module in this invention;

[0028] Figure 6 This is the circuit schematic of the current output module in this invention. Detailed Implementation

[0029] like Figures 1-6 As shown, the present invention provides a detection circuit for ignition current, including an ignition current sampling module, a comparison module, and a triggering module;

[0030] The comparison module, connected to the detonation current sampling module, is used to determine whether there is an ignition current.

[0031] The trigger module is connected to both the detonation current sampling module and the comparison module. It is used to receive the output signal of the comparison module and send a level trigger signal to the detonation current sampling module.

[0032] The detonation current sampling module includes:

[0033] The current sampling unit is connected to both the ignition circuit and the comparison module. It is used to sample the input current and send the current signal to the comparison module.

[0034] The sample-and-hold unit, connected to the current sampling unit and the trigger module, is used to sample and register the input current according to the level trigger signal and hold the peak current output.

[0035] The detection circuit also includes a compensation module connected to the current sampling unit for offset voltage compensation. The detection circuit also includes a current output module connected to both the current sampling unit and the control module for outputting the sampled input current to the control module. The control module includes a microcontroller for acquiring instantaneous current information and performing signal processing.

[0036] The detonation current sampling module includes resistors R1-R7, capacitors C1-C7, a Schottky diode D1, a current sensor U1, an operational amplifier U2, and a sample-and-hold circuit U3. One end of resistor R1 is connected to the output terminal of the ignition circuit, and the other end of resistor R1 is connected to pins 1 and 2 of current sensor U1. One end of capacitor C1 is connected to pin 8 of current sensor U1 and then connected to a 3.3V power supply; the other end of capacitor C1 is grounded. One end of capacitor C2 is connected to pin 5 of current sensor U1 and then grounded; the other end of capacitor C2 is connected to pin 6 of current sensor U1. Pin 7 of current sensor U1 is connected to one end of capacitor C3 and one end of resistor R2. The other end of resistor R2 is connected to one end of resistor R3 and pin 3 of operational amplifier U2. Pin 2 of operational amplifier U2 is connected to one end of resistors R4 and R5. The other end of resistor R4... One end of the resistor R5 is grounded. The other end of the resistor R5 is connected to pin 1 of the op-amp U2 and pin 1 of the Schottky diode D1. Pins 2 and 3 of the Schottky diode D1 and one end of the resistor R6 are connected to the pins of the capacitor C4 and pin 3 of the sample-and-hold circuit U3. The other end of the capacitor C4 is grounded. One end of the capacitor C7 is connected to pin 7 of the sample-and-hold circuit U3 and then grounded. The other end of the capacitor C7 is connected to pin 6 of the sample-and-hold circuit U3. One end of the capacitor C5 is connected to pin 1 of the sample-and-hold circuit U3 and then connected to the 12V power supply. The other end of the capacitor C5 is grounded. One end of the capacitor C6 is connected to pin 4 of the sample-and-hold circuit U3 and then connected to the -12V power supply. The other end of the capacitor C6 is grounded. One end of the resistor R7 is connected to pin 5 of the sample-and-hold circuit U3. The other end of the resistor R7 is connected to the microcontroller.

[0037] The comparison module includes resistors R8 to R11, capacitor C8, and comparator U4. One end of resistor R8 is connected to pin 4 of comparator U4, and the other end of resistor R8 is connected to a 3.3V power supply. Pin 1 of comparator U4 is connected to pin 3 of sample-and-hold circuit U3. Pin 3 of comparator U4 is connected to one end of resistors R9 and R10. The other end of resistor R9 is connected to a 3.3V power supply. The other end of resistor R10 is connected to one end of resistor R11, and the other end of resistor R11 is grounded. One end of capacitor C8 is connected to pin 5 of comparator U4 and then connected to a 5V power supply. The other end of capacitor C8 is connected to pin 2 of comparator U4 and then grounded.

[0038] The trigger module includes resistor R12, capacitors C9 and C10, and D flip-flop U5. Pin 1 of D flip-flop U5 is connected to pin 4 of comparator U4, pin 2 of D flip-flop U5 is connected to a 3.3V power supply, pin 4 of D flip-flop U5 is grounded, one end of resistor R12 is connected to pin 3 of D flip-flop U5, pin 8 of comparator U4 is connected to the other end of resistor R12 and one end of capacitor C9, one end of capacitor C10 is connected to pins 7 and 8 of D flip-flop U5 and then connected to a 3.3V power supply, and the other end of capacitor C10 is grounded.

[0039] The compensation module includes resistors R13 to R15, capacitor C11, and operational amplifier U6. Pin 5 of operational amplifier U6 is connected to one end of resistors R13 and R14. The other end of resistor R13 is connected to a 3.3V power supply. Pins 6 and 7 of operational amplifier U6 are connected to the other end of resistor R3. The other end of resistor R14 is connected to one end of resistor R15. The other end of resistor R15 is connected to one end of capacitor C11 and pin 4 of operational amplifier U6, and then grounded. The other end of capacitor C11 is connected to a 3.3V power supply.

[0040] The current output module includes capacitor C12 and voltage follower U7. Pin 3 of voltage follower U7 is connected to pin 7 of current sensor U1. Pins 1 and 4 of voltage follower U7 are connected to the output of the ignition circuit. One end of capacitor C12 is connected to pin 5 of voltage follower U7 and then connected to a 3.3V power supply. The other end of capacitor C12 is connected to pin 2 of voltage follower U7 and then grounded. The HS_out terminal in the figure is connected to the microcontroller.

[0041] The current sensor U1, sample-and-hold circuit U3, and voltage follower U7 all use existing chip devices, and any device that meets the corresponding function can be used. The current sensor U1 is a Hall sensor chip, which has the function of detecting the magnitude of the current. The sample-and-hold circuit U3 has a sample-and-hold function. The voltage follower U7 has a voltage following function.

[0042] A method for detecting ignition current includes the following steps:

[0043] The input signal is sampled at the output of the self-ignition circuit.

[0044] Determine whether there is current input based on the sampled input signal;

[0045] If there is current input, the trigger module sends a high-level signal to the sample and hold unit to sample and register the input ignition current and hold the peak current output.

[0046] If there is no current input, the trigger module sends a low-level signal to the sample-and-hold unit and outputs the signal in response to the input signal.

[0047] In this invention, the detonation current sampling adopts an isolated Hall current sensor + single-peak sample-and-hold circuit scheme, which can quickly sample I_out and roughly depict the discharge curve. Specifically, the Vcap terminal and the NMOS D terminal are connected in series to the output terminal of the ignition circuit. The comparator U4 determines whether there is current input, thereby determining whether detonation has occurred. If detonation has occurred, the comparator U4 triggers the D flip-flop U5, which sends a high-level signal to the sample-and-hold circuit U3, thereby holding the current peak value. The obtained current peak signal I_ADC can be sent to the microcontroller for easy acquisition and processing by the microcontroller.

[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0049] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A detection circuit for ignition current, characterized in that, Includes an initiation current sampling module, a comparison module, and a triggering module; The comparison module is connected to the detonation current sampling module and is used to determine whether there is an ignition current. The triggering module is connected to both the detonation current sampling module and the comparison module, and is used to receive the output signal of the comparison module and send a level trigger signal to the detonation current sampling module. The detonation current sampling module includes: The current sampling unit is connected to both the ignition circuit and the comparison module. It is used to sample the input current and send the current signal to the comparison module. The sample-and-hold unit is connected to both the current sampling unit and the trigger module. It is used to sample and register the input current according to the level trigger signal and hold the peak current output. The detection circuit further includes a compensation module, which is connected to the current sampling unit and is used to compensate for the offset voltage of the current sampling unit. The detonation current sampling module includes resistors R1-R7, capacitors C1-C7, a Schottky diode D1, a current sensor U1, an operational amplifier U2, and a sample-and-hold circuit U3. One end of resistor R1 is connected to the output terminal of the ignition circuit, and the other end of resistor R1 is connected to pins 1 and 2 of the current sensor U1. One end of capacitor C1 is connected to pin 8 of the current sensor U1 and then connected to a 3.3V power supply; the other end of capacitor C1 is grounded. One end of capacitor C2 is connected to pin 5 of the current sensor U1 and then grounded; the other end of capacitor C2 is connected to pin 6 of the current sensor U1. Pin 7 of the current sensor U1 is connected to one end of capacitor C3 and one end of resistor R2. The other end of resistor R2 is connected to one end of resistor R3 and pin 3 of operational amplifier U2. Pin 2 of operational amplifier U2 is connected to one end of resistors R4 and R5. The other end of resistor R4 is grounded. The other end of resistor R5 is connected to pin 1 of operational amplifier U2 and pin 1 of Schottky diode D1. Pins 2 and 3 of Schottky diode D1 and one end of resistor R6 are connected. The other end of resistor R6 is connected to one end of capacitor C4 and pin 3 of sample-and-hold circuit U3. The other end of capacitor C4 is grounded. One end of capacitor C7 is connected to pin 7 of sample-and-hold circuit U3 and then grounded. The other end of capacitor C7 is connected to pin 6 of sample-and-hold circuit U3. One end of capacitor C5 is connected to pin 1 of sample-and-hold circuit U3 and then connected to a 12V power supply. The other end of capacitor C5 is grounded. One end of capacitor C6 is connected to pin 4 of sample-and-hold circuit U3 and then connected to a -12V power supply. The other end of capacitor C6 is grounded. One end of resistor R7 is connected to pin 5 of sample-and-hold circuit U3. The comparison module includes resistors R8-R11, capacitor C8, and comparator U4. One end of resistor R8 is connected to pin 4 of comparator U4, and the other end of resistor R8 is connected to a 3.3V power supply. Pin 1 of comparator U4 is connected to pin 3 of sample-and-hold circuit U3. Pin 3 of comparator U4 is connected to one end of resistors R9 and R10. The other end of resistor R9 is connected to the 3.3V power supply. The other end of resistor R10 is connected to one end of resistor R11. The other end of resistor R11 is grounded. One end of capacitor C8 is connected to pin 5 of comparator U4 and then connected to a 5V power supply. The other end of capacitor C8 is connected to pin 2 of comparator U4 and then grounded. The trigger module includes a resistor R12, capacitors C9 and C10, and a D flip-flop U5. Pin 1 of the D flip-flop U5 is connected to pin 4 of the comparator U4, pin 2 of the D flip-flop U5 is connected to a 3.3V power supply, pin 4 of the D flip-flop U5 is grounded, one end of the resistor R12 is connected to pin 3 of the D flip-flop U5, pin 8 of the comparator U4 is connected to the other end of the resistor R12 and one end of the capacitor C9, one end of the capacitor C10 is connected to pins 7 and 8 of the D flip-flop U5 and then connected to the 3.3V power supply, and the other end of the capacitor C10 is grounded. The compensation module includes resistors R13-R15, capacitor C11, and operational amplifier U6. Pin 5 of operational amplifier U6 is connected to one end of resistors R13 and R14. The other end of resistor R13 is connected to a 3.3V power supply. Pins 6 and 7 of operational amplifier U6 are connected to the other end of resistor R3. The other end of resistor R14 is connected to one end of resistor R15. The other end of resistor R15 is connected to one end of capacitor C11 and pin 4 of operational amplifier U6, and then grounded. The other end of capacitor C11 is connected to a 3.3V power supply. The detection method using an ignition current detection circuit includes the following steps: The input signal is sampled at the output of the self-ignition circuit. Determine whether there is current input based on the sampled input signal; If there is current input, the trigger module sends a high-level signal to the sample and hold unit to sample and register the input ignition current and hold the peak current output. If there is no current input, the trigger module sends a low-level signal to the sample-and-hold unit and outputs the signal in response to the input signal.

2. The ignition current detection circuit according to claim 1, characterized in that, The detection circuit also includes a current output module, which is connected to both the current sampling unit and the control module, and is used to output the sampled input current to the control module; the control module includes a microcontroller to collect instantaneous current information and perform signal processing.

3. The ignition current detection circuit according to claim 2, characterized in that, The current output module includes a capacitor C12 and a voltage follower U7. Pin 3 of the voltage follower U7 is connected to pin 7 of the current sensor U1. Pins 1 and 4 of the voltage follower U7 are connected to the output terminal of the ignition circuit. One end of the capacitor C12 is connected to pin 5 of the voltage follower U7 and then connected to a 3.3V power supply. The other end of the capacitor C12 is connected to pin 2 of the voltage follower U7 and then grounded.

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