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.
Gallium Nitride (GaN) technology is a relatively new semiconductor technology used primarily in markets such as defense, aerospace, telecommunications infrastructure, and satellite communications.As t...
The upcoming Circuit Playground Bluefruit is an upgraded version of the Circuit Playground Express. It uses the nRF52840 microcontroller and supports Bluetooth BLE function.Product Specifications1 x n...
[i=s]This post was last edited by Jacktang on 2019-5-19 00:01[/i] [color=#555555][font="][size=4]Provides key runtime software components and documentation to further simplify development. The followi...
Some people may be confused by a bunch of theoretical knowledge when using an oscilloscope for the first time, and thus lose interest in learning. If we can first learn how to measure a simple signal,...
Microsoft Asia and IDC Asia/Pacific released the findings of a study on the manufacturing industry titled “Preparing for a Great Future: Assessing Growth in Asia Pacific Driven by Artificial Intellig...[Details]
0 Introduction
At present, both China and foreign countries are vigorously developing electric vehicles. As the core component of electric vehicles , the performance of the drive system direct...[Details]
Today, the flagships of major mainstream manufacturers are all around 6.7 inches without exception. Everyone knows the advantages of large screens, but there is never a lack of demand for small-scree...[Details]
The memory structure of the AT89S52 microcontroller is divided into four parts: on-chip program memory, off-chip program memory, on-chip data memory, and off-chip data memory.
1. Program memory
...[Details]
introduction One of the key factors in achieving high reliability, performance and long life for battery packs designed into HEV, PHEV and EV powertrains is the electronics used in the battery ...[Details]
Many systems with embedded ARM processors are based on battery-powered energy supply, and the power consumption of the processor is critical to the entire SoC chip, so the low power consumption advant...[Details]
The 21 special function registers (26 in the 52 series) are discontinuously distributed in the 128-byte SFR storage space, and the address space is 80H-FFH. In this SFR space, there is a 128-bit addr...[Details]
1. (1) Read the contents of file1.txt (for example):
12
34
56
is output to file2.txt:
56
34
12
(in reverse order)
Answer:
Note the use of growable arrays.
#include stdio.h
#...[Details]
An automatic dialing alarm was made using 89C2051. The alarm uses the redial function of the telephone to alarm. It has a simple circuit, small size, stable performance, no false alarms, and no impact...[Details]
CYT34065 can design 36V-24V or even lower than 12V buck drive circuit, CV or CC mode, and step down to an output voltage of more than 1.25V. CYT34065 still meets the output DC constant voltage mode d...[Details]
The oscilloscope is also called a handheld oscilloscope, which is easy to carry and easy to operate. It can transform invisible electrical signals into visible images, making it easier for people to ...[Details]
Industrial robot simulation software is a software tool used to simulate the operation process of industrial robots. They can help engineers and technicians test and optimize robots before actual a...[Details]
Pre-configured CryptoAuthentication™ ICs help reduce development time and minimize design costs
Secure key provisioning is critical to protecting sensitive keys from third-party tamp...[Details]
Analog electronics
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