CN107835339B - Locking protection method and system for CMOS image sensor of space camera - Google Patents
Locking protection method and system for CMOS image sensor of space camera Download PDFInfo
- Publication number
- CN107835339B CN107835339B CN201710913687.1A CN201710913687A CN107835339B CN 107835339 B CN107835339 B CN 107835339B CN 201710913687 A CN201710913687 A CN 201710913687A CN 107835339 B CN107835339 B CN 107835339B
- Authority
- CN
- China
- Prior art keywords
- image sensor
- cmos image
- camera
- current
- camera controller
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/50—Constructional details
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/006—Calibration or setting of parameters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
- H02H3/087—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current for dc applications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/40—Circuit details for pick-up tubes
- H04N23/41—Beam current control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/50—Constructional details
- H04N23/55—Optical parts specially adapted for electronic image sensors; Mounting thereof
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/70—SSIS architectures; Circuits associated therewith
- H04N25/76—Addressed sensors, e.g. MOS or CMOS sensors
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Studio Devices (AREA)
Abstract
The invention discloses a locking protection system and a locking protection method for a CMOS image sensor of a space camera, which solve the defects that the application range is small, the current limiting threshold value is a fixed value, the current limiting threshold value is difficult to match with the locking current of a protected device, the protected device cannot be separated from a locking state, misjudgment is easy to cause, the service life of the CMOS image sensor is influenced and the like in the conventional system and method. The locking protection system of the space camera CMOS image sensor comprises a DC-DC module, a magnetic latching relay, a precision resistor, a current limiting type low-voltage difference regulator, a precision operational amplifier, an A/D conversion module, a camera controller CPU, an instruction driver and a nonvolatile memory. The locking protection method of the CMOS image sensor of the space camera starts A/D conversion at a frequency which is more than 10 times of the highest fluctuation frequency of the working current of the CMOS image sensor, continuously samples more than 2 longest fluctuation cycles of the working current of the CMOS image sensor, and the code value range corresponding to the normal work of the CMOS image sensor can be modified after the spacecraft is launched to avoid misjudgment.
Description
Technical Field
The present invention relates generally to space cameras employing CMOS image sensors, and more particularly to space camera CMOS image sensor lock-in protection systems and methods.
Background
The space camera takes a spacecraft as an observation platform and images the earth or other stars such as the moon and the mars. The cosmic space (especially the cosmic space outside the earth's atmosphere) contains gamma rays, X rays, electrons, protons, neutrons and various heavy ions, and the radiation effect of the gamma rays, the X rays, the electrons, the protons, the neutrons and the heavy ions can damage photoelectric devices in the space camera, so that the space camera works abnormally or fails. The radiation effect of the space radiation on the space camera mainly comprises total radiation dose, single event effect and displacement effect. The Single Event effect refers to transient disturbance or permanent damage of a Single high-energy particle impact on an electronic device, and is divided into a Single Event function interruption effect (also referred to as Single Event reversal effect, Single Event Upset, SEU for short) and a Single Event locking effect (also referred to as Single Event Latch effect, Single Event Latch, SEL for short). If the single-particle locking effect does not have good protection measures, the high current generated by the low resistance state can fuse the metal wire in the device, permanent damage is caused, and the device is even burnt out and cannot be recovered.
The space camera generally uses a Charge Coupled Device (CCD) or a CMOS as an image sensor for photoelectric conversion, and with the development of CMOS image sensor technology, the CCD is gradually replaced by the CMOS image sensor, and the space camera is also more and more widely applied. When the CMOS image sensor is subjected to single-particle locking, the supply current can be increased sharply, and if no protective measures are taken, the CMOS image sensor can be damaged or even directly scrapped. At present, a current-limiting resistor or a current-limiting type Low dropout regulator (also called a Low dropout regulator, Low drop regulator, LDO for short) is usually added in a power supply loop in a space camera for lock protection (guo, research on radiation-resistant strategy of remote sensing CCD camera, china optics and applied optics, 2010, 3(6): 534-. However, the method of adding a current limiting resistor in the supply loop can only be used for CMOS integrated devices with a dynamic operating current of 10mA and a latch-up current/operating current > 20.
The current-limiting type low dropout regulator is characterized in that when the output current exceeds a threshold value, the output current is maintained to be the threshold value, the direct burning of an image sensor caused by the excessive current is avoided, and the threshold value is related to the model of the current-limiting type low dropout regulator, such as that MAX883 is 430mA (see MAX883 data manual). However, this method still has the following disadvantages:
first, since the threshold of the current-limiting type low dropout regulator is related to the model of the current-limiting type low dropout regulator (generally, a fixed value), it is difficult to match the locking current of the protected device. When the locking current of the protected device is smaller than the threshold of the current-limiting type low-voltage-difference regulator, the current of the current-limiting type low-voltage-difference regulator can be limited to the threshold of the current-limiting type low-voltage-difference regulator only when the protected device is locked, and the protected device cannot be separated from the locking state. When the current-limiting type low dropout regulator and the CMOS image sensor are in a threshold current state, a large amount of heat is generated, and if the current-limiting type low dropout regulator and the CMOS image sensor are in the threshold current state for a long time, the device is overheated, the service life of the CMOS image sensor is influenced, and the CMOS image sensor and the current-limiting type low dropout regulator are still possibly burnt.
Secondly, in the working process of the CMOS image sensor, the working current of the CMOS image sensor greatly fluctuates by taking a line period/a frame period as a period, and misjudgment is easily caused by single threshold judgment, so that the misoperation of a protection circuit is caused, and the normal work of the space camera is influenced. Meanwhile, due to the influence of the total dose of spatial radiation, the working current of the CMOS image sensor changes greatly after working for years when the CMOS image sensor is relatively just emitted, and if the locking protection circuit still judges according to the previous threshold value, misjudgment is easily caused, so that the protection circuit malfunctions, and the normal work of the spatial camera is influenced.
Disclosure of Invention
The invention provides a locking protection system and a locking protection method for a space camera CMOS image sensor, aiming at the defects that the space camera adopting the CMOS image sensor has small application range, the current limiting threshold value is a fixed value, the current limiting threshold value is difficult to be matched with the locking current of a protected device, the protected device cannot be separated from the locking state, misjudgment is easy to cause, the service life of the CMOS image sensor is influenced and the like.
The technical scheme adopted by the invention for solving the technical problem is as follows:
a locking protection system for a CMOS image sensor of a space camera comprises a DC-DC module (10), a magnetic latching relay (20), a precision resistor (30), a current-limiting type low-voltage difference regulator (40), a precision operational amplifier (50), an A/D conversion module (60), a camera controller CPU (70), an instruction driver (80) and a nonvolatile memory (90);
the DC-DC module (10) is used for converting a first voltage of the whole satellite power supply into a second voltage used by the space camera, the converted second voltage is sent to the magnetic latching relay (20), and the DC-DC module (10) is also used for isolating the whole satellite power supply and the camera power supply;
the magnetic latching relay (20) is used for opening or closing a relay switch under the control of instructions to power on or off the CMOS image sensor; the input of the switch of the magnetic latching relay (20) is the output of the DC-DC module (10) and is output to the precision resistor (30); the input of the coil of the magnetic latching relay (20) is the output of a command driver (80), when the command driver outputs a positive direct current pulse, a relay switch is opened, a CMOS image sensor is powered on, when the command driver outputs a reverse direct current pulse, the relay switch is closed, and the CMOS image sensor is powered off;
the precision resistor (30) is used for converting the current of the CMOS image sensor during operation into voltage for subsequent amplification and detection; the input of the precision resistor (30) is the output of the magnetic latching relay (20), and a second voltage signal used by the camera is output to the current-limiting type low-voltage-difference regulator (40) after passing through the precision resistor (30); the input end and the output end of the precision resistor (30) are respectively sent to the positive input end and the negative input end of the precision operational amplifier (50) so as to facilitate subsequent signal amplification;
the current-limiting type low-voltage difference regulator (40) is used for converting a second voltage signal received from the precision resistor (30) and used by the camera into a voltage directly used by the CMOS image sensor and supplying power to the CMOS image sensor; the current-limiting type low-voltage difference regulator (40) is also used for limiting the output current to a current limiting value if the working current exceeds the current limiting value of the current-limiting type low-voltage difference regulator (40) when the CMOS image sensor has single-particle locking;
the precision operational amplifier (50) is used for amplifying the voltage at two ends of the precision resistor (30) so as to be matched with the dynamic range of the A/D conversion module (60); the input of the precise operational amplifier (50) is two ends of the precise resistor (30), and the voltage amplified by the precise operational amplifier (50) is sent to the A/D conversion module (60);
the A/D conversion module (60) is used for performing analog-to-digital conversion on the voltage signal output by the precise operational amplifier (50) and converting the voltage signal into a digital quantity so as to be processed by a camera controller CPU (70); the input of the A/D conversion module (60) is the output of the precise operational amplifier (50), and the digital quantity obtained after the conversion of the A/D conversion module (60) is sent to a camera controller CPU (70);
the camera controller CPU (70) is used for reading a code value range corresponding to the normal work of the CMOS image sensor from the nonvolatile memory (90) according to the digital quantity output by the A/D conversion module (60), and controlling the power-on and power-off of the magnetic latching relay through the instruction driver (80) according to a control instruction received by the satellite host to realize the locking protection of the CMOS image sensor; when a camera controller CPU (70) receives a code value range corresponding to the normal work of a new CMOS image sensor sent by a satellite host, writing the code value range corresponding to the normal work of the CMOS image sensor into a nonvolatile memory (90); the input of the camera controller CPU (70) comprises a digital quantity output by the A/D conversion module (60), a code value range corresponding to the normal work of the CMOS image sensor read from the nonvolatile memory (90) and a control instruction received from the star host; the output of the camera controller CPU (70) is positive direct current pulse or reverse direct current pulse, and is output to the instruction driver (80);
the instruction driver (80) is used for driving the magnetic latching relay (20) to work after amplifying the positive direct current pulse or the reverse direct current pulse output by the CPU (70) of the camera controller, so that the switch of the magnetic latching relay is opened or closed; the input of the command driver (80) is the output of the camera controller CPU (70), which is output to the magnetic latching relay (20);
the nonvolatile memory (90) is used for storing a code value range corresponding to the normal work of the CMOS image sensor, and when the locking protection function of the CMOS image sensor is opened, the nonvolatile memory (90) outputs the code value range corresponding to the normal work of the CMOS image sensor to the camera controller CPU (70); when the camera controller CPU (70) receives a code value range corresponding to the normal work of a new CMOS image sensor sent by the star mainframe, the nonvolatile memory (90) inputs the code value range corresponding to the normal work of the new CMOS image sensor from the camera controller CPU (70).
The inventor also provides a method for locking protection of a space camera CMOS image sensor, which is characterized by comprising the following steps:
step one, after receiving an imaging start instruction sent by a satellite host, a camera controller CPU (70) sends a positive direct current pulse through an instruction driver (80) to close a magnetic latching relay (20), and then step two is executed;
step two, the whole satellite power supply is converted by the DC-DC module (10), then passes through the magnetic latching relay (20), the precision resistor (30) and the current limiting type low-voltage difference regulator (40) to supply power to the CMOS image sensor, starts imaging, and then executes step three;
step three, the voltage difference between two ends of the precision resistor (30) is amplified by the precision operational amplifier (50) and then sent to the A/D conversion module (60), and then step four is executed;
step four, the CPU (70) of the camera controller starts A/D conversion at a frequency which is more than 10 times of the highest fluctuation frequency of the working current of the CMOS image sensor, continuously samples more than 2 working current of the CMOS image sensor for the longest fluctuation period, and then executes step five;
step five, the camera controller CPU (70) judges whether the locking protection function is opened according to a CMOS image sensor locking protection setting instruction sent by the star host, if so, the step six is executed, otherwise, the step ten is executed;
step six, the camera controller CPU (70) judges whether the minimum value of the code value obtained by sampling after being converted into current is larger than 1.5 times of the minimum value of the normal working current of the CMOS image sensor or larger than 0.95 times of the minimum value of the locking threshold current, if so, the step seven is executed, otherwise, the step ten is executed;
step seven, the CPU (70) of the camera controller sends reverse direct current pulse through an instruction driver (80) to disconnect a magnetic latching relay (20) and power off the CMOS image sensor, and then step eight is executed;
step eight, the camera controller CPU (70) informs the star service host computer CMOS image sensor of locking through a bus on the star through telemetering quantity, and then executes step nine;
step nine, the housekeeping host cuts off the power supply of the satellite to the whole camera subsystem, so that the camera is isolated from other subsystems on the satellite, and then the operation is finished;
step ten, the camera controller CPU (70) judges whether an imaging closing instruction sent by the star mainframe is received, if so, the step eleven is executed, otherwise, the step three is returned;
step eleven, the camera controller CPU (70) sends reverse direct current pulse through the instruction driver (80), so that the magnetic latching relay (20) is switched off, the CMOS image sensor is powered off, imaging is finished, and then the step I is returned.
Further, the method comprises the steps of:
before a spacecraft carried by a space camera is launched, a code value range corresponding to the normal work of the CMOS image sensor is calibrated and modified in a laboratory.
Further, the method comprises the steps of:
after the spacecraft carried by the space camera is launched, the ground measurement and control station sends the space camera to the spacecraft through the measurement and control antenna, and the space camera is forwarded by the satellite host to modify the code value range corresponding to the normal work of the CMOS image sensor.
Compared with the prior art, the technical scheme provided by the invention has the following advantages that:
1. the threshold value of the locking protection can be adjusted according to the actual condition of the protected CMOS image sensor, so that the problem that the protection threshold value is difficult to match with the locking current of the protected device in the existing method is solved, the situation that the protected device cannot be separated from the locking state is avoided, and the service life of the CMOS image sensor is not influenced.
2. Aiming at the dynamic change of the working current in the working process of the CMOS image sensor, the A/D conversion and sampling are carried out at the frequency which is more than 10 times of the highest fluctuation frequency of the working current of the CMOS image sensor, and more than the longest fluctuation cycle of the working current of 2 CMOS image sensors are continuously sampled, so that the misjudgment caused by single threshold judgment is avoided, the misoperation of a protection circuit is caused, and the normal work of the space camera is influenced.
And 3, when the CMOS image sensor is locked, the CMOS image sensor and the peripheral circuit thereof are quickly and completely disconnected from the power supply by controlling the relay switch, so that physical isolation is realized, the fault is prevented from spreading to other related circuits of the camera through the power supply system, and finally the power supply of the satellite to the whole camera subsystem is cut off through the satellite host, so that the camera is isolated from other subsystems on the satellite, and the safety of the whole satellite and other subsystems is ensured.
4. The locking protection function can be turned on or turned off through an above-ground injection instruction, the code value range corresponding to the normal work of the CMOS image sensor can be sent to the spacecraft by the ground measurement and control station through the measurement and control antenna after being transmitted by the spacecraft carried by the space camera, and the code value range is modified after being forwarded to the space camera by the satellite host. The phenomenon that the working current of the CMOS image sensor is changed greatly relatively when the CMOS image sensor is just transmitted after working for years under the action of the total dose of space radiation, so that misjudgment is caused, the misoperation of a protection circuit is caused, and the long-life reliable work of a space camera is ensured. The locking protection function can be closed when the protection circuit fails, and the camera can normally work when the single event locking effect does not occur.
Drawings
FIG. 1 is a block diagram of a space camera CMOS image sensor lock-in protection system in one embodiment of the present invention;
FIG. 2 is a detailed flow chart of a method for lock-in protection of a space camera CMOS image sensor in one embodiment of the present invention;
reference numerals:
10. a DC-DC module;
20. a magnetic latching relay;
30. precision resistance;
40. a flow-limiting type low pressure difference regulator;
50. a precision operational amplifier;
60. an A/D conversion module;
70. a camera controller CPU;
80. an instruction driver;
90. a non-volatile memory.
Detailed Description
To explain technical contents, structural features, and objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.
A preferred embodiment of the present invention will be described in detail with reference to fig. 1 to 2. As shown in fig. 1, the system for space camera CMOS image sensor lock-in protection comprises a DC-DC module 10, a magnetic latching relay 20, a precision resistor 30, a current limiting type low-voltage difference adjuster 40, a precision operational amplifier 50, an a/D conversion module 60, a camera controller CPU70, an instruction driver 80, and a nonvolatile memory 90. The camera power supply system is characterized in that the DC-DC module (10) is used for converting the whole satellite power supply with higher voltage (namely, a first voltage, usually 28-42V) into a lower voltage (namely, a second voltage, usually 0-15V) used by the camera, the converted lower voltage is transmitted to the magnetic latching relay (20), and the DC-DC module has the other function of isolating the whole satellite power supply and the camera power supply to a certain degree and ensuring the safety;
the magnetic latching relay (20) is used for opening or closing a relay switch under the control of instructions to power on or off the CMOS image sensor. The input of the switch of the magnetic latching relay (20) is the output of the DC-DC module (10) and is output to the precision resistor (30). The input of the coil of the magnetic latching relay (20) is the output of a command driver (80), when the command driver outputs a positive direct current pulse, a relay switch is opened, the CMOS image sensor is powered on, when the command driver outputs a reverse direct current pulse, the relay switch is closed, and the CMOS image sensor is powered off.
The precision resistor (30) is used for converting the current of the CMOS image sensor during operation into voltage for subsequent amplification and detection. The input of the precision resistor (30) is the output of the magnetic latching relay (20), and a lower voltage signal used by the camera is output to the current-limiting type low-voltage difference regulator (40) after passing through the precision resistor (30). The input end and the output end of the precision resistor (30) are respectively sent to the positive input end and the negative input end of the precision operational amplifier (50) so as to facilitate subsequent signal amplification. The precision resistor refers to a resistor with resistance error, thermal stability (temperature coefficient), distribution parameters (distributed capacitance and distributed inductance) of the resistor meeting certain standards. In general, for a resistor having a resistance of 1 Ω (ohm) or more, a resistor having a resistance error within ± 0.5% from the reference resistance may be referred to as a precision resistor.
The current limiting type low voltage difference regulator (40) is used for converting a lower voltage signal (namely, a second voltage) received from the precision resistor (30) and used by a camera into a voltage (usually 0-5V) directly used by the CMOS image sensor to supply power to the CMOS image sensor. The current-limiting type low-voltage difference regulator (40) has the other function that when the CMOS image sensor is subjected to single-particle locking, if the working current exceeds the current-limiting value of the current-limiting type low-voltage difference regulator (40), the current-limiting type low-voltage difference regulator (40) limits the output current to the current-limiting value, and the phenomenon that the CMOS image sensor is damaged due to the fact that the current supplied to the CMOS image sensor at a certain moment is overlarge is avoided.
The precision operational amplifier (50) is used for amplifying the voltage at two ends of the precision resistor (30) so as to be matched with the dynamic range of the A/D conversion module (60) and reduce the quantization error of the A/D conversion. The input of the precise operational amplifier (50) is two ends of the precise resistor (30), and the voltage amplified by the precise operational amplifier (50) is sent to the A/D conversion module (60).
The A/D conversion module (60) is used for carrying out A/D (analog/digital) conversion on the voltage signal output by the precise operational amplifier (50) and converting the voltage signal into a digital quantity so as to be processed by a camera controller CPU (70). The input of the A/D conversion module (60) is the output of the precise operational amplifier (50), and the digital quantity obtained after the conversion of the A/D conversion module (60) is sent to the camera controller CPU (70).
The camera controller CPU (70) is used for controlling the power-on and power-off of the magnetic latching relay through the instruction driver (80) according to the digital quantity output by the A/D conversion module (60), the code value range corresponding to the normal work of the CMOS image sensor read from the nonvolatile memory (90) and the control instruction received from the satellite host, so that the locking protection of the CMOS image sensor is realized. When the camera controller CPU (70) receives a code value range corresponding to the normal work of a new CMOS image sensor sent by the star host, the code value range corresponding to the normal work of the CMOS image sensor is written into the nonvolatile memory (90). The input of the camera controller CPU (70) comprises a digital quantity output by the A/D conversion module (60), a code value range corresponding to the normal work of the CMOS image sensor read from the nonvolatile memory (90) and a control instruction received from the star host. The output of the camera controller CPU (70) is a positive DC pulse or a negative DC pulse, and is output to the command driver (80).
And the instruction driver (80) is used for driving the magnetic latching relay (20) to work after amplifying the positive direct current pulse or the reverse direct current pulse output by the CPU (70) of the camera controller, so that the switch of the magnetic latching relay is opened or closed. The input of the command driver (80) is the output of the camera controller CPU (70), which is output to the magnetic latching relay (20).
The nonvolatile memory (90) is used for storing a code value range corresponding to the normal work of the CMOS image sensor, and when the locking protection function of the CMOS image sensor is opened, the nonvolatile memory (90) outputs the code value range corresponding to the normal work of the CMOS image sensor to the camera controller CPU (70). When the camera controller CPU (70) receives a code value range corresponding to the normal work of a new CMOS image sensor sent by the star mainframe, the nonvolatile memory (90) inputs the code value range corresponding to the normal work of the new CMOS image sensor from the camera controller CPU (70).
In this embodiment, the DC-DC module (10) adopts Mhv2805S/883 from endpoint corporation, and its input is supplied with power by 30V whole satellite, output is 5V, and output power is 15W. The magnetic latching relay (20) adopts 3JB20-3 of Guilin space electronics Limited company, and the precision resistor (30) adopts a0.03 ohm precision alloy foil resistor (rated power 3W) produced by ISA company. The current limiting low dropout regulator (40) uses MAXIM MAX883, with a current limiting threshold of 430 mA. The accurate operational amplifier (50) adopts RH6105 of Rilierte company, the gain accuracy is better than 1%, and the input common mode rejection and the power supply rejection exceed 100 dB. The A/D conversion module (60) uses AD574, and the quantization bit is 12 bits. The CPU70 adopts a TSC695F of ACTEL company and a TSC695F which is a 32-bit processor with the total radiation dose up to 300Krad (Si), and adopts an error correction and detection mechanism to improve the reliability according to the characteristics of space application. The instruction driver (80) adopts KG25A of the institute of Western-ampere microelectronics, the nonvolatile memory (90) adopts 3Dplus EEPROM, the concrete model is 3DEE5M40CS5175, and the storage capacity is 128 Kx 40 bits. It should be noted that the types of the above components (such as the DC-DC module, the current limiting type low dropout regulator, etc.) are only one embodiment of the present invention, and in the practical application process, other types of related components can be selected according to the practical needs to work, and the system or the method disclosed by the present invention is also applicable.
In the embodiment, the method for locking and protecting the CMOS image sensor of the space camera is described with reference to fig. 2, and is characterized by comprising the following steps:
step one, after receiving an imaging start command sent by a star host, a camera controller CPU (70) (TSC695F) sends a positive direct current pulse through a command driver (80) (KG25A) to close a magnetic latching relay (20) (3JB20-3), and then step two is executed;
step two, the whole satellite power supply is converted by a DC-DC module (10) (Mhv2805S/883), then passes through a magnetic latching relay (20) (3JB20-3), a precision resistor (30) (ISA0.03 ohm precision alloy foil resistor) and a current-limiting type low-voltage difference regulator (40) (MAX883) to supply power to the CMOS image sensor, imaging is started, and then step three is executed;
step three, the voltage difference between two ends of the precision resistor (30) (ISA0.03 ohm precision alloy foil resistor) is amplified by the precision operational amplifier (50) (RH6105) and then sent to the A/D conversion module (60) (AD574), and then step four is executed;
step four, a camera controller CPU (70) (TSC695F) starts A/D conversion at a frequency which is more than 10 times of the highest fluctuation frequency of the working current of the CMOS image sensor, continuously samples more than 2 working current of the CMOS image sensor for the longest fluctuation period, and then executes step five;
step five, a camera controller CPU (70) (TSC695F) judges whether a locking protection function is opened according to a CMOS image sensor locking protection setting instruction sent by a star host, if so, the step six is executed, otherwise, the step ten is executed;
step six, the camera controller CPU (70) (TSC695F) judges whether the minimum value after the code value obtained by sampling is converted into the current is larger than 1.5 times of the minimum value of the normal working current of the CMOS image sensor or larger than 0.95 times of the minimum value of the locking threshold current, if so, the step seven is executed, otherwise, the step ten is executed;
step seven, the camera controller CPU (70) (TSC695F) sends an inverse direct current pulse through the command driver (80) (KG25A) to disconnect the magnetic latching relay (20) (3JB20-3) and power off the CMOS image sensor, and then step eight is executed;
step eight, the camera controller CPU (70) (TSC695F) informs the star service host computer that the CMOS image sensor is locked through the on-board bus by a telemetering amount, and then step nine is executed;
step nine, the housekeeping host cuts off the power supply of the satellite to the whole camera subsystem, so that the camera is isolated from other subsystems on the satellite, and then the operation is finished;
step ten, the camera controller CPU (70) (TSC695F) judges whether an imaging closing instruction sent by the star mainframe is received, if so, the step eleven is executed, otherwise, the step three is returned;
step eleven, the camera controller CPU (70) (TSC695F) sends an inverse direct current pulse through the command driver (80) (KG25A) to turn off the magnetic latching relay (20) (3JB20-3) to power off the CMOS image sensor, and imaging is finished, and then the process returns to step one.
In this embodiment, the CMOS image sensor used is GL1216 of cheng core, the power supplies required for the sensor are 3.6V, 3.2V and 1.8V, and the power supplies are obtained by voltage conversion using 3 pieces of MAX883, and the inputs of the 3 pieces of MAX883 are all outputs of the precision resistor (30) (ISA0.03 ohm precision alloy foil resistor). The operating current of GL1216 and a peripheral power supply circuit thereof fluctuates by taking a line period as a period in the laboratory measurement photographing process, the minimum value of the fluctuation is 370mA, the maximum value is 500mA, the amplification factor of a precise operational amplifier (50) (RH6105) is set to be 200 times, the voltage after corresponding power amplification is 2.22V-3V, the reference voltage adopted by an AD574 is 5V, 12bit quantization is adopted, and the code value after A/D conversion is 1819-2458. The minimum working current is 1.5 times 555mA, and corresponds to a code value 2728 after A/D conversion. In other embodiments, the CMOS image sensor and the precision resistor may be of other types according to actual needs.
The line period of the space camera is 2-5ms, so in step four, the A/D conversion is started at the frequency which is more than 10 times of the highest fluctuation frequency of the working current of the CMOS image sensor, namely 5000 Hz, and 2 maximum fluctuation periods of the working current of the CMOS image sensor, namely more than 10ms, are continuously sampled. The code value obtained by sampling is downloaded through telemetering, when the CMOS image sensor works under the action of the total space radiation dose, the working current of the CMOS image sensor has larger change compared with that of the CMOS image sensor when the CMOS image sensor is just transmitted after working for years, according to the downloaded telemetering, the CMOS image sensor can be sent to a spacecraft through a measurement and control antenna by a ground measurement and control station, and the code value range corresponding to the normal work of the CMOS image sensor is modified after the CMOS image sensor is forwarded to a space camera by a satellite host. When the camera controller CPU (70) (TSC695F) receives the code value range corresponding to the normal operation of the new CMOS image sensor from the star master, the nonvolatile memory (90) (3DEE5M40CS5175) inputs the code value range corresponding to the normal operation of the new CMOS image sensor from the camera controller CPU (70) (TSC 695F).
Single event experiments prove that when single event locking occurs, the 3.6V supply current of GL1216 can be increased by 100mA, and if the locking state cannot be relieved, the current can be continuously increased to 430mA of the current limiting threshold of MAX 883. That is, the minimum value of the locking threshold current of the operating current of the GL1216 and its peripheral power supply circuit is 470mA (minimum value 370mA plus 100mA), and 0.95 times of the locking threshold current is 446.5mA, which corresponds to the code value 2195 after A/D conversion. And step six, judging whether the minimum value of the code value obtained by sampling after the code value is converted into the current is greater than 1.5 times of the minimum value of the normal working current of the CMOS image sensor or greater than 0.95 time of the minimum value of the locking threshold current, namely judging whether the code value obtained by sampling is greater than 2728 or 2195, if so, judging that single event locking occurs, and executing step seven, otherwise, executing step ten.
It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein, or by using equivalent structures or equivalent processes performed in the content of the present specification and the attached drawings, which are included in the scope of the present invention.
Claims (4)
1. A locking protection system for a CMOS image sensor of a space camera comprises a DC-DC module (10), a magnetic latching relay (20), a precision resistor (30), a current-limiting type low-voltage difference regulator (40), a precision operational amplifier (50), an A/D conversion module (60), a camera controller CPU (70), an instruction driver (80) and a nonvolatile memory (90); it is characterized in that the utility model is characterized in that,
the DC-DC module (10) is used for converting a first voltage of the whole satellite power supply into a second voltage used by the space camera, the converted second voltage is sent to the magnetic latching relay (20), and the DC-DC module (10) is also used for isolating the whole satellite power supply and the camera power supply;
the magnetic latching relay (20) is used for opening or closing a relay switch under the control of instructions to power on or off the CMOS image sensor; the input of the switch of the magnetic latching relay (20) is the output of the DC-DC module (10) and is output to the precision resistor (30); the input of the coil of the magnetic latching relay (20) is the output of a command driver (80), when the command driver outputs a positive direct current pulse, a relay switch is opened, a CMOS image sensor is powered on, when the command driver outputs a reverse direct current pulse, the relay switch is closed, and the CMOS image sensor is powered off;
the precision resistor (30) is used for converting the current of the CMOS image sensor during operation into voltage for subsequent amplification and detection; the input of the precision resistor (30) is the output of the magnetic latching relay (20), and a second voltage signal used by the camera is output to the current-limiting type low-voltage-difference regulator (40) after passing through the precision resistor (30); the input end and the output end of the precision resistor (30) are respectively sent to the positive input end and the negative input end of the precision operational amplifier (50) so as to facilitate subsequent signal amplification;
the current-limiting type low-voltage difference regulator (40) is used for converting a second voltage signal received from the precision resistor (30) and used by the camera into a voltage directly used by the CMOS image sensor and supplying power to the CMOS image sensor; the current-limiting type low-voltage difference regulator (40) is also used for limiting the output current to a current limiting value if the working current exceeds the current limiting value of the current-limiting type low-voltage difference regulator (40) when the CMOS image sensor has single-particle locking;
the precision operational amplifier (50) is used for amplifying the voltage at two ends of the precision resistor (30) so as to be matched with the dynamic range of the A/D conversion module (60); the input of the precise operational amplifier (50) is two ends of the precise resistor (30), and the voltage amplified by the precise operational amplifier (50) is sent to the A/D conversion module (60);
the A/D conversion module (60) is used for performing analog-to-digital conversion on the voltage signal output by the precise operational amplifier (50) and converting the voltage signal into a digital quantity so as to be processed by a camera controller CPU (70); the input of the A/D conversion module (60) is the output of the precise operational amplifier (50), and the digital quantity obtained after the conversion of the A/D conversion module (60) is sent to a camera controller CPU (70);
the camera controller CPU (70) is used for reading a code value range corresponding to the normal work of the CMOS image sensor from the nonvolatile memory (90) according to the digital quantity output by the A/D conversion module (60), and controlling the power-on and power-off of the magnetic latching relay through the instruction driver (80) according to a control instruction received by the satellite host to realize the locking protection of the CMOS image sensor; when a camera controller CPU (70) receives a code value range corresponding to the normal work of a new CMOS image sensor sent by a satellite host, writing the code value range corresponding to the normal work of the CMOS image sensor into a nonvolatile memory (90); the input of the camera controller CPU (70) comprises a digital quantity output by the A/D conversion module (60), a code value range corresponding to the normal work of the CMOS image sensor read from the nonvolatile memory (90) and a control instruction received from the star host; the output of the camera controller CPU (70) is positive direct current pulse or reverse direct current pulse, and is output to the instruction driver (80);
the instruction driver (80) is used for driving the magnetic latching relay (20) to work after amplifying the positive direct current pulse or the reverse direct current pulse output by the CPU (70) of the camera controller, so that the switch of the magnetic latching relay is opened or closed; the input of the command driver (80) is the output of the camera controller CPU (70), which is output to the magnetic latching relay (20);
the nonvolatile memory (90) is used for storing a code value range corresponding to the normal work of the CMOS image sensor, and when the locking protection function of the CMOS image sensor is opened, the nonvolatile memory (90) outputs the code value range corresponding to the normal work of the CMOS image sensor to the camera controller CPU (70); when the camera controller CPU (70) receives a code value range corresponding to the normal work of a new CMOS image sensor sent by the star host, the nonvolatile memory (90) inputs the code value range corresponding to the normal work of the new CMOS image sensor from the camera controller CPU (70);
the camera controller CPU (70) is used for reading a code value range corresponding to normal work of the CMOS image sensor from the nonvolatile memory (90) according to the digital quantity output by the A/D conversion module (60), controlling power-on and power-off of the magnetic latching relay through the instruction driver (80) according to a control instruction received by the satellite host, and realizing locking protection of the CMOS image sensor by the following method:
the camera controller CPU (70) judges whether the locking protection function is opened according to a CMOS image sensor locking protection setting instruction sent by the star host:
when the locking protection function is opened, the camera controller CPU (70) judges whether the minimum value of the code value obtained by sampling after being converted into current is more than 1.5 times of the minimum value of the normal working current of the CMOS image sensor or more than 0.95 times of the minimum value of the locking threshold current;
when the minimum value of the code value obtained by sampling of the camera controller CPU (70) after being converted into the current is more than 1.5 times of the minimum value of the normal working current of the CMOS image sensor or more than 0.95 times of the minimum value of the locking threshold current, the camera controller CPU (70) sends a reverse direct current pulse through an instruction driver (80) to disconnect a magnetic latching relay (20) and power off the CMOS image sensor.
2. A method for locking and protecting a CMOS image sensor of a space camera is characterized by comprising the following steps:
step one, after receiving an imaging start instruction sent by a satellite host, a camera controller CPU (70) sends a positive direct current pulse through an instruction driver (80) to close a magnetic latching relay (20), and then step two is executed;
step two, the whole satellite power supply is converted by the DC-DC module (10), then passes through the magnetic latching relay (20), the precision resistor (30) and the current limiting type low-voltage difference regulator (40) to supply power to the CMOS image sensor, starts imaging, and then executes step three;
step three, the voltage difference between two ends of the precision resistor (30) is amplified by the precision operational amplifier (50) and then sent to the A/D conversion module (60), and then step four is executed;
step four, the CPU (70) of the camera controller starts A/D conversion at a frequency which is more than 10 times of the highest fluctuation frequency of the working current of the CMOS image sensor, continuously samples more than 2 working current of the CMOS image sensor for the longest fluctuation period, and then executes step five;
step five, the camera controller CPU (70) judges whether the locking protection function is opened according to a CMOS image sensor locking protection setting instruction sent by the star host, if so, the step six is executed, otherwise, the step ten is executed;
step six, the camera controller CPU (70) judges whether the minimum value of the code value obtained by sampling after being converted into current is larger than 1.5 times of the minimum value of the normal working current of the CMOS image sensor or larger than 0.95 times of the minimum value of the locking threshold current, if so, the step seven is executed, otherwise, the step ten is executed;
step seven, the CPU (70) of the camera controller sends reverse direct current pulse through an instruction driver (80) to disconnect a magnetic latching relay (20) and power off the CMOS image sensor, and then step eight is executed;
step eight, the camera controller CPU (70) informs the star service host computer CMOS image sensor of locking through a bus on the star through telemetering quantity, and then executes step nine;
step nine, the housekeeping host cuts off the power supply of the satellite to the whole camera subsystem, so that the camera is isolated from other subsystems on the satellite, and then the operation is finished;
step ten, the camera controller CPU (70) judges whether an imaging closing instruction sent by the star mainframe is received, if so, the step eleven is executed, otherwise, the step three is returned;
step eleven, the camera controller CPU (70) sends reverse direct current pulse through the instruction driver (80), so that the magnetic latching relay (20) is switched off, the CMOS image sensor is powered off, imaging is finished, and then the step I is returned.
3. The method of space camera CMOS image sensor lock protection according to claim 2, comprising the steps of:
before a spacecraft carried by a space camera is launched, a code value range corresponding to the normal work of the CMOS image sensor is calibrated and modified in a laboratory.
4. The method of space camera CMOS image sensor lock protection according to claim 2, comprising the steps of:
after the spacecraft carried by the space camera is launched, the ground measurement and control station sends the space camera to the spacecraft through the measurement and control antenna, and the space camera is forwarded by the satellite host to modify the code value range corresponding to the normal work of the CMOS image sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710913687.1A CN107835339B (en) | 2017-09-30 | 2017-09-30 | Locking protection method and system for CMOS image sensor of space camera |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710913687.1A CN107835339B (en) | 2017-09-30 | 2017-09-30 | Locking protection method and system for CMOS image sensor of space camera |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107835339A CN107835339A (en) | 2018-03-23 |
| CN107835339B true CN107835339B (en) | 2019-12-27 |
Family
ID=61647692
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710913687.1A Active CN107835339B (en) | 2017-09-30 | 2017-09-30 | Locking protection method and system for CMOS image sensor of space camera |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107835339B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110988440A (en) * | 2019-12-19 | 2020-04-10 | 上海微阱电子科技有限公司 | Current monitoring device and method of CMOS device |
| CN113377143B (en) * | 2021-04-25 | 2023-03-31 | 北京控制工程研究所 | Deep space exploration color camera self-recovery anti-single particle locking system and method |
| CN113363933B (en) * | 2021-06-07 | 2022-08-23 | 中国科学院光电技术研究所 | Single event effect protection device and method |
| CN114326473A (en) * | 2021-11-30 | 2022-04-12 | 中国科学院长春光学精密机械与物理研究所 | Program control instruction circuit for on-track operation of space optical remote sensor |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201464767U (en) * | 2009-06-05 | 2010-05-12 | 北京空间机电研究所 | Power distribution protective circuit of multispectral remote sensing CCD camera power supply |
| CN102053882A (en) * | 2011-01-11 | 2011-05-11 | 北京航空航天大学 | Heterogeneous satellite-borne fault-tolerant computer based on COTS (Commercial Off The Shelf) device |
| CN103701087A (en) * | 2013-11-28 | 2014-04-02 | 兰州空间技术物理研究所 | On-track monitoring method for space single event latchup effect |
| CN104714580A (en) * | 2015-03-09 | 2015-06-17 | 中国科学院长春光学精密机械与物理研究所 | Improved magnetic latching relay satellite-borne camera power supply system |
-
2017
- 2017-09-30 CN CN201710913687.1A patent/CN107835339B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201464767U (en) * | 2009-06-05 | 2010-05-12 | 北京空间机电研究所 | Power distribution protective circuit of multispectral remote sensing CCD camera power supply |
| CN102053882A (en) * | 2011-01-11 | 2011-05-11 | 北京航空航天大学 | Heterogeneous satellite-borne fault-tolerant computer based on COTS (Commercial Off The Shelf) device |
| CN103701087A (en) * | 2013-11-28 | 2014-04-02 | 兰州空间技术物理研究所 | On-track monitoring method for space single event latchup effect |
| CN104714580A (en) * | 2015-03-09 | 2015-06-17 | 中国科学院长春光学精密机械与物理研究所 | Improved magnetic latching relay satellite-borne camera power supply system |
Non-Patent Citations (2)
| Title |
|---|
| CMOS 器件单粒子锁定效应及其防护设计;吕强等;《通信对抗》;20151231;第34卷(第4期);全文 * |
| 空间单粒子锁定效应研究;薛玉雄等;《核技术》;20120930;第35卷(第9期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107835339A (en) | 2018-03-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107835339B (en) | Locking protection method and system for CMOS image sensor of space camera | |
| US10969814B2 (en) | Bandgap reference voltage failure detection | |
| US9030794B2 (en) | Electronic fuse apparatus and method of operating the same | |
| DE112010001323B4 (en) | Power supply control and control method therefor | |
| US7755327B2 (en) | Synchronous rectification type battery charging circuit and protection circuit thereof | |
| US9172243B2 (en) | Shut-off circuits for latched active ESD FET | |
| US20120182004A1 (en) | Power supply controller | |
| TWI695245B (en) | Voltage Regulator | |
| CN104237685B (en) | A kind of space single particle effect test method | |
| US20160329807A1 (en) | Over-current recovery including overshoot suppression | |
| CN102340246A (en) | Thick-film magnetic isolation direct current solid-state power controller | |
| US20200033901A1 (en) | Voltage control circuit, method and device, and storage medium | |
| US10277220B2 (en) | Hot swap circuit management techniques for power line disturbances and faults | |
| CN102207409B (en) | A kind of temperature sensing circuit | |
| CN208053127U (en) | A kind of power-off of charging gun pipette tips self solves lock system | |
| CN104375549B (en) | A kind of anti-latch circuit of cmos device | |
| CN101336399B (en) | Two level current limiting power supply system | |
| US5010321A (en) | Nuclear event detectors | |
| US9280429B2 (en) | Power fail latching based on monitoring multiple power supply voltages in a storage device | |
| CN109756103B (en) | Power supply and distribution control system and control method for space flight verification platform | |
| CN110361618A (en) | One kind being used for cmos image sensor single event latch-up effect test method | |
| CN110492431A (en) | The single event latch-up protective device and clear-latch method of charge measurement chip | |
| US8610415B2 (en) | Lambda correction for current foldback | |
| CN106208198B (en) | A kind of battery discharge regulator output overvoltage protection circuit | |
| CN103683924B (en) | The controller of tool defencive function |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |