The properly and electrostatically measured taping materials are used for the components, but attention should be paid to the fact that there is some danger the parts absorb on the top
tapes to cause a failure in the mounting and the parts are destructed by static electricity (more than 1kV : 1J, 2A, 2B, 2E 0.5kV : 1E, Human Body Model 100pF 1.5kΩ) to change the
resistance in the conditions of an excessive dryness or after the parts are given vibration for a long time as they are packaged on the tapes. Similarly, care should be given not to apply the
excessive static electricity when mounting on the boards.
●
Ionic impurities such as flux etc. that are attached to these products or those mounted onto a PCB, negatively affect their moisture resistance, corrosion resistance, etc. The flux may
contain ionic substances like chlorine, acid, etc. while perspiration and saliva include ionic impurities like sodium (Na
＋
), chrorine (Cl
−
) etc. Therefore these kinds of ionic substances may
induce electrical corrosion when they invade into the products. Either thorough washing or using RMA solder and flux are necessary since lead free solder contains ionic substances.
Washing process is needed, before putting on moisture proof material in order to prevent electrical corrosion.
●
Please pay attention that the top of an iron does not direct touch to the components. There is a risk that may cause a change in resistance. Take care that another risk may happen that
the protecting coat is carbonized in an instant when touched directly by the top of the iron, also climatic-proof for electric corrosion or insulation of protecting coat may be dropped down.
Be sure not to give high temperature on the top of the iron as it will degrade the protecting coat.
●
Avoid storing components under direct sun rays, high temperature/humidity. Direct sun rays will cause quality change of taping and difficulty of keeping appropriate peeling strength. 5∼
35℃/35∼75%RH, there is no deterioration of solderability for 12 months, but take special care for storing, because condensation, dust, and toxic gas like hydrogen sulfide, sulfurous acid
gas, hydrogen chloride, etc. may drop solderability.
1. OverviewFLYYANG unattended intelligent weighing management system is mainly composed of electronic truck scale, computer, printer, video surveillance, wireless radio frequency card reading system, ...
"200 Examples of Monolithic Switching Power Supply Design" comprehensively, deeply and systematically explains the practical circuit design of monolithic switching power supplies. The book selects the...
The physical design of the PCB board is the last step in the design of switching power supplies. If the design method is not appropriate, the PCB may radiate too much electromagnetic interference, cau...
Dear forum friends, in the DCDC part of the above picture or the usual four-layer board, the middle layer of gray-yellow will be paved with copper to form a complete ground, but there is basically no ...
Question to everyone: Isn't esp32 a dual-mode wifi and BLE device?
Why doesn't micropython include functions for BLE? Isn't ESP32 just a slightly more powerful 8266?[b]Additional content (2020-3-22 17...
China Energy Storage Network:
The barren saline-alkali beach was hard to find birds and plants. Now, it is a hotbed for development and a livable new district, with spring tides surging on th...[Details]
1 System Structure
According to the performance requirements of the system, the resonance source system is mainly composed of six parts: computer control software, USB communication, CPU modul...[Details]
According to foreign media reports, Tesla CEO Elon Musk recently expressed his hope to complete improvements to the Autopilot core basic code and 3D labels to provide better functions for vehicles. ...[Details]
Summary This article explores ADI’s new and broadly marketed LIDAR prototyping platform and how it helps customers shorten product development time by providing a complete hardware and software so...[Details]
According to foreign media reports, on August 20, local time, the US Patent and Trademark Office granted Apple 53 new patents, two of which are related to Apple's Titan Project. The first patent invo...[Details]
Today, Shenzhen Yueshi Robotics
Technology Co., Ltd. (hereinafter referred to as "Yueshi Robotics")
, a cold chain cloud factory platform
, completed tens of millions of yuan in Pre-A2 round...[Details]
Modern information warfare places high demands on target detection in complex backgrounds. Compared with radar, visible light and other detection technologies, infrared imaging detection has good c...[Details]
Analog Devices CN0534 LNA Receiver Reference Design Now Available at Mouser Electronics Boosting 5.8GHz ISM Applications April 15, 2022 – Mouser Electronics, the industry leader in New Product I...[Details]
On the morning of March 26, according to a new smartphone ranking released today by Consumer Reports, Apple's iPhone 12 Pro Max became one of the best smartphones in 2021, Samsung's Galaxy No...[Details]
NXP Semiconductors announced the launch of its new product, MIFARE DESFire EV3 IC, which provides a new generation of high performance, advanced security features and seamlessly integrated mobile ser...[Details]
introduction
The most common flight state of a fixed-wing aircraft is horizontal flight. If it is allowed to fly at a large angle, the action cannot be maintained all the time. If it is al...[Details]
According to Jiwei.com, due to the shortage of copper foil in recent years, insufficient raw materials have restricted the capacity expansion and capacity utilization rate improvement of the copper c...[Details]
According to the news released by Sino-Singapore Guangzhou Knowledge City, Guangdong Microelectronics' 12-inch chip project started production on June 15, with the goal of officially going into mass ...[Details]
On November 4, the HuanDa 97.5MW/390MWh shared energy storage power station project started construction in the Beidaqiao new energy planning area of Guazhou County. Image It is understood that this...[Details]
RF/Wirelessly
京公网安备 11010802033920号
EEWORLD
