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.
MPS EVM38111-R-00A : Dual-channel 6V, 1A, synchronous buck power module evaluation board with integrated inductor (value: 179.75 yuan) is an evaluation board used to demonstrate the performance of the...
[i=s]This post was last edited by Wuzu Simeng on 2022-11-22 23:05[/i]After unpacking it for a week, I found that this weight loss tool is really good. I successfully lost 0.5 kg, but I gained it back ...
This post uses common commands to perform some tests.
Get CPU temperature information
The V853 chip has a Temperature Monitor module inside.
cat /sys/class/thermal/thermal_zone0/temp
result
The displa...
Test SD card reading and writing, switch USB to Host mode
cat /sys/devices/platform/soc/usbc0/usb_hostInsert SD card promptAutomatically mount to /mnt/sdcardthe directorydd copy command
The dd command...
Live Topic: Introduction to new features of FSP4.0.0 of Renesas Electronics RA series product development tools
Live broadcast time: 10:00-11:30 this morning
Live Introduction: This presentation will ...
Microchip's PIC18F46J50 is a low-power, high-performance 8-bit USB microcontroller (MCU) using nanoWatt XLP technology. The current in deep sleep mode can be as low as 13nA, the operating voltage i...[Details]
No matter which processor you are learning, the first thing you need to understand is the registers and working mode of the processor.
ARM has 37 registers, including 31 general registers and ...[Details]
All electronic design engineers and scientists have performed electrical signal analysis, or signal analysis for short. Through this basic measurement, they can gain insight into signal details and...[Details]
Two simple circuits are implemented to drive two LEDs from a battery powered microprocessor.
This design is based on a circuit that uses three resistors and a microprocessor I/O pin as an input h...[Details]
From the PIC16F946 datasheet, we know that there are two ways to write values to the LCD for display:
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2. Use disconnect t...[Details]
1. Introduction
At present, most lighting equipment still uses traditional energy for lighting. Making full use of solar energy as the energy supply for lighting equipment is of great si...[Details]
Microcalorimetry
is used to determine energy relationships. Microcalorimetry techniques are often required when performing calorimetric experiments with small sample sizes or slow heating rat...[Details]
1. Background:
The instrument system parameter detection and control of the chemical production workshop of Tangshan Coal Gas Coking Plant are all analog instruments, some of which are eve...[Details]
Overview:
This paper introduces a method of connecting a CAN-bus network with Ethernet to form a medium-sized remote monitoring/data transmission network.
CAN (Controller Area Network) is ...[Details]
Many battery-powered systems require a visual indicator to show when the battery needs to be replaced. LEDs are commonly used for this purpose, but they consume at least 10mA of current. This con...[Details]
With the advocacy and implementation of the government's Safe City Plan, the security market has increasingly higher requirements for the clarity of surveillance images. Imagine that after a case o...[Details]
Investment in
the
medical device
industry has been on the rise in recent years. In the past two years, venture capital for medical devices has almost doubled, reaching $4 billion in 2007. Fr...[Details]
Recently, news came from the certification department that the photovoltaic grid-connected inverter of Samil New Energy Co., Ltd. (hereinafter referred to as "Samil New Energy") has once again obta...[Details]
1. Proposal of
reconfigurable
measurement and control system
The measurement and control system generally refers to a system based on
computers
to realize data acquisition a...[Details]
With the rapid development of wireless
digital communication
, more challenges have been raised for integrated circuit design and testing. In the product design stage, in order to ensure
t...[Details]
Power technology
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