I. System Overview
Before the 1970s, PCB detection mainly rely on the human eye plus magnifying glass to detect slow, undetected rate, at the same time, can lead to decreased visual acuity test personnel, affect human health; later developed into the electrical test, the principle is based on the PCB line computer data design diagram and the corresponding pair of needle beds fixture outlets testing procedures. When tested, the probe pressed against the surface of the PCB test points, then power-off test each network and report defects of short circuit and open circuit. Its limitation is that only detect other defects ① short circuit and open circuit two defects, nicks, pinholes and residual copper can not be detected. ② needle bed fixture high cost, small batch inappropriate; but with the further development of electronic assembly to a higher density, smaller size, more complex PCB hybrid technology, relying on only the human eye to detect or electrical testing of printed circuit quality board can not meet the quality requirements. To improve product quality, reduce the next step of the process the board has a number of defects, the need for PCB testing key equipment ---- automated optical inspection (AOI) systems is also growing.
2. System Requirements
The whole system requires a long time to work on the master device requiring high reliability;
Master the whole system installed on the terminal, the terminal whole system is generally placed in the workshop, and with automatic conveyor systems, influenced by the vibration, dust and other harsh environments;
Because few large ones need to collect data, the corresponding interface is not much need to expand, usually 1-2 can be;
Because you want to print the test results, it is necessary to print interface;
Due to the commissioning of equipment, setting parameters, show results, etc., so VGA interface, PS2 interface (separate) is required;
Because of the need to connect a number of PLC control device, so the COM port is a must;
Because the testing process, if unusual, must require timely warning, so motherboard must bring their own buzzer, testing procedures typically use this buzzer;
The main control system to complete the information collection, processing, analysis, transmission and communications functions, CPU performance is not too low, but generally does not require too much business, you can apply.
3. System Description
AOI is detected PCB graphics quality surface (such as surface defects, open circuit and short circuit) equipment for the production of semi-finished products quality inspection process, it is a high-precision single-layer PCB, especially in key technology multilayer PCB processing. Test system optics, precision machinery, to identify diagnostic algorithms and computer technologies. Detection, the machine by a charge coupled device (CCD) or laser automatically scans PCB, capture images evacuation and computer processing, and then compared with a database of standard data, to identify defects on the PCB, with the display or display or automatic identification system identifies defects for maintenance personnel repaired.
4.Product master list of five items: EVOC EPI machine IPC-6805E
The master board is a use Intel G41 chipset supports Intel LGA775 package dual-core, quad-core high-performance platform E5300, E8400, Q9400 CPU series; and support two 800 / 1066M DDR3 memory, the total capacity of the largest support 4GB; onboard a 10/100 / 1000Mbps network interface; support for VGA + VGA dual display function; Support 4 SATA interfaces; 8 USB 2.0 ports, two serial ports (of which one supports RS-232 / RS-422 / RS-485), 1 parallel port and other rich I / O interfaces.
The master device using the floor between EVOC EPI2.0 bus design, motherboard and chassis, backplane connection between the expansion card and application in all European connector to achieve.
The whole chassis is a compact wall cabinet, small size, occupying limited space of the whole system; the chassis made of high quality steel plate, high-temperature baking spray paint, solid structure. It has excellent heat, vibration, and radiation performance out. Used to meet the vibration, electromagnetic interference and other harsh work environment.
5 .EVOC Advantages
EVOC EPI bus between the system design, the motherboard and backplane, backplane and expansion cards between all European connector pinhole connection, 360-degree surround contact with high air tightness, oxidation corrosion resistance, dust resistance, etc., to solve the When working in dusty, humid, high / low temperature, corrosion and other harsh industrial environments and easy inter-connector plug, electrical oxidation or mold caused by poor contact, to ensure the reliability of the work of IPC, motherboard or expansion card Once inserted in place, European-style connector male and female head does not occur between the contact surfaces relative displacement, no relative friction, will not damage the conductive layer, to enhance the ability of the system of anti-vibration and shock, ensure equipment reliability in vibration environments for a long time work requirements;
CPU backplane unique stent design, the CPU heatsink weight turret to the metal chassis, to avoid imbalance between the European connector contact force, while more stable between the two connectors, no relative displacement, to further improve the In the vibration environment of the machine the ability to operate reliably.
EPI bus computer to solve the traditional industrial computer platform can not cheat powered through the floor, causing the chassis alignment complex; EPI bus definition PS-ON #, 5V SBS (2A) and other signals, 12V power supply has five pins can withstand current 7A, Avoid control connection between the bottom plate and the use of ATX motherboard power.
EPI optimized PCI bus backplane traces and traces ISA, PCI traces shorter, easier to match traces, makes the PCI and ISA signal quality has been greatly improved, to ensure the reliability of the system;
Open architecture: "EVOC-EPCI bus technology ------ Enhanced PCI bus expansion card configuration, signal definition standard" completely free license.
6.EVOC EPI bus products in harsh industrial environments with long trouble-free and stable operation characteristics, can satisfy the dusty, humid, under a variety of harsh environment of high / low temperature, corrosion, vibration and other hardware requirements.