CN-122000834-A - Protection device for photoelectric detector assembly

CN122000834ACN 122000834 ACN122000834 ACN 122000834ACN-122000834-A

Abstract

The invention belongs to the technical field of photoelectric detectors, and particularly discloses a protection device for a photoelectric detector assembly, which comprises a high-low voltage protection module for forming a plurality of paths of positive and negative power supplies, wherein the protection module comprises a load switch, a sampler, a comparator and a control logic module, the load switch is arranged between a fuse of a load circuit and a load, the sampler is used for sampling load voltage, the comparator is used for comparing the sampled load voltage with reference voltage, and the control logic module is used for receiving output signals of the comparators and controlling the on-off of the load switches. The invention successfully solves the protection problem of multi-path overvoltage and overcurrent of positive low pressure, negative low pressure and negative high pressure and the over-temperature protection problem existing in the condition of over-high ambient temperature in one device, realizes one machine for multiple purposes, and reduces the volume and complexity of the system.

Inventors

BAI MIN
DENG DAWEI
QIN PENGFEI
QIU KAIQIANG
LI SENMAO

Assignees

重庆鹰谷光电股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260311

Claims (8)

1. A protection device for a photoelectric detector assembly is characterized by comprising a positive power supply high-low voltage protection module, a negative power supply low-voltage protection module and a logic control module which form a plurality of paths, wherein the positive power supply high-low voltage protection module comprises a positive power supply low-voltage protection module, a negative power supply low-voltage protection module and a negative power supply high-voltage protection module, The positive power supply low-voltage protection module comprises a first load switch, a first sampler and a first comparator, wherein the positive power supply low voltage is output to a load through a first fuse and the first load switch, the first sampler samples the voltage of the output end of the first load switch and sends the voltage to the first comparator, and the first comparator compares the voltage of the output end of the first load switch with a reference voltage and outputs a signal to the control logic module; The negative power supply low-voltage protection module comprises a second load switch, a second sampler and a second comparator, wherein the negative power supply low voltage is output to a load through a second fuse and the second load switch, the second sampler samples the voltage of the output end of the second load switch and sends the voltage to the second comparator, and the second comparator compares the voltage of the output end of the second load switch with a reference voltage and outputs a signal to the control logic module; The negative power supply high-voltage protection module comprises a third load switch, a third sampler and a third comparator, wherein the negative power supply high voltage is output to a load through a third fuse and the third load switch, the third sampler samples the voltage of the output end of the third load switch and sends the voltage to the third comparator, and the third comparator compares the voltage of the output end of the third load switch with a reference voltage and outputs a signal to the control logic module; The control logic module receives output signals of the first comparator, the second comparator and the third comparator and uniformly controls the on-off of the first load switch, the second load switch and the third load switch; The over-temperature protection module comprises a temperature sensor, a fourth sampler and a fourth comparator, wherein the temperature sensor is used for detecting the ambient temperature of a detected piece in real time and converting detection signals into electric signals, the fourth sampler samples the electric signals output by the temperature sensor and sends the electric signals to the fourth comparator, the fourth comparator compares the electric signals output by the temperature sensor with reference voltages and outputs signals to the control logic module, and the control logic module uniformly controls the on-off of each load switch.
2. The protection device for a photodetector assembly of claim 1, further comprising a status indicator light, said comparator, status indicator light and control logic module forming a separate loop, said comparator output signal driving the status indicator light.
3. The protection device for a photodetector assembly of claim 1, wherein said load switch employs a photo MOS relay, said first and second load switches employ photo MOS relays AQV252G, and said third load switch employs photo MOS relays AQV259AX.
4. The protective apparatus for a photodetector assembly of claim 1, wherein said sampler employs more than two series resistance voltage division samples.
5. The protection device for a photodetector assembly of claim 1, wherein said comparator employs a comparator TLV1701 that supports negative pressure input.
6. The protection device for a photodetector assembly of claim 1, wherein said control logic module is an RS latch comprised of a digital logic chip CD 4011.
7. The protection device for a photodetector assembly according to claim 1, wherein said control logic module is provided with a manual reset button.
8. The protection device for a photodetector assembly of claim 1, wherein said temperature sensor employs LM35.

Description

Protection device for photoelectric detector assembly Technical Field The invention belongs to the technical field of photoelectric detectors, and particularly relates to a protection device of a photoelectric detector assembly. Background The photoelectric detector component is a core component in the fields of fuze, guidance, detection and the like. The laser radar detector emits laser by a laser, then the detector receives a target reflected laser echo signal, the photoelectric effect is utilized to convert the optical signal into an electric signal, the photoelectric conversion is realized, and an electric pulse signal with a certain pulse width is formed after the electric pulse signal is processed by a pre-amplification circuit, and meanwhile, the attenuation function of a front discharge circuit is realized. The photodiodes of such detector assemblies typically operate at a specific high negative voltage, with the subsequent operational amplifier operating at both positive and negative voltages, while such detector assemblies themselves are very fragile, extremely sensitive to over-currents and voltages, and may be permanently damaged by small electrical shocks. In practical application and test process, overvoltage or overcurrent pulse is easily introduced due to power supply starting transient state, misoperation (such as miswiring), electrostatic discharge or external interference and the like, so that irreversible damage is caused to the expensive photoelectric detection component. In the prior art, although there are protection schemes such as a simple fuse or TVS tube or a power supply chip with overcurrent and overvoltage or the like, the following defects exist: 1. The protection scheme is single, and a traditional protection circuit is usually designed aiming at a single voltage level, so that positive low voltage, negative low voltage and extremely high negative voltage are difficult to process optimally in the same device. 2. The high voltage processing is complex-600V high voltage, and it is common practice to sample using complex level shifting circuits or high voltage differential amplifiers, resulting in complex circuitry, high cost and reduced reliability. 3. The negative pressure treatment is inconvenient, and for negative pressure lines such as-15V, an additional negative pressure conversion circuit or operational amplifier is usually required, so that the number of elements and the design complexity are increased. 4. The system integration level is low, unified and reliable linkage control logic is lacked among multiple independent protection circuits, and fault state maintaining and resetting mechanisms are not concise and reliable. Thus, there is a strong need for a multi-way voltage protection solution that can provide fast, accurate, automatic recovery and integration for photodetector assemblies. Disclosure of Invention Therefore, the present invention is directed to an integrated multi-channel overvoltage and overcurrent protection device, which can provide comprehensive protection for positive low voltage, negative low voltage and high negative voltage power supply paths for a photodetector assembly, and can also detect the ambient temperature of a measured object, and immediately cut off the power supply of the measured object once the ambient temperature exceeds a preset ambient temperature. In order to achieve the above purpose, the present invention provides the following technical solutions: The invention provides a protection device for a photoelectric detector assembly, which comprises a positive and negative power supply high and low voltage protection module forming a plurality of paths, wherein the protection module comprises: a load switch mounted between a fuse of a load circuit and a load; The sampler is used for sampling load voltage; a comparator for comparing the sampled load voltage with a reference voltage; And the control logic module is used for receiving the output signals of the comparators and controlling the on-off of the load switches. Further, the protection device comprises a positive power supply low-voltage protection module, a negative power supply low-voltage protection module and a negative power supply high-voltage protection module, The positive power supply low-voltage protection module comprises a first load switch, a first sampler and a first comparator, wherein the positive power supply low voltage is output to a load through a first fuse and the first load switch, the first sampler samples the voltage of the output end of the first load switch and sends the voltage to the first comparator, and the first comparator compares the voltage of the output end of the first load switch with a reference voltage and outputs a signal to the control logic module; The negative power supply low-voltage protection module comprises a second load switch, a second sampler and a second comparator, wherein the negative power supply low voltage is output to