The substrate of chip resistors is alumina. Cracks may occur at the connection of solder (solder fillet portion) due to the difference of the coefficient of thermal expansion from a
mounting board when heat stress like heat cycle, etc. are repeatedly given to them. Care should be taken to the occurrence of the cracks when the change in ambient temperature or
ON/OFF of load is repeated, especially when large types of W2H/W3A which have large thermal expansion and also self heating. By general temperature cycle test using glass-
epoxy(FR-4) boards under the maximum/minimum temperatures of operating temperature range, the crack does not occur easily in the types of 1E〜2E, but the crack tends to
occur in the types of W2H/W3A. The occurrence of the crack by heat stress may be influenced by the size of a pad, solder volume, heat radiation of mounting board etc., so please
pay careful attention to designing when a big change in ambient temperature and conditions for use like ON/OFF of load can be assumed.
I want to do some electronic circuit experiments, but I don't have a stable power supply. I hope to have a power supply that can convert 220V mains electricity into 5V, 15V, -15V stable voltage (at le...
Using the mc55 module embedded TCPIP protocol to implement ping and ftp 1. When setting the ftp username and password, it always reports input parameter errors 2. Unable to write data after establishi...
How to design the circuit to achieve the following functions? 1. When the control circuit is in an idle state (when there is no output to drive the load, the current required for the control circuit t...
[align=center][font=Tahoma] [b][size=5]Abstract[/size][/b][/font][/align][align=left][font=Tahoma] [/font][/align][align=left][font=Tahoma] Power electronics applications are extensive, ranging from n...
Assume that data is read from 8-bit AD (if it is a higher-bit AD, the data type can be defined as int), the subroutine is get_ad();
1. Limited secondary filtering
/* A value can be adjust...[Details]
0 Introduction
With the development of my country's economy, the number of motor vehicles continues to increase. The growth of existing roads and other hardware facilities can no longer meet t...[Details]
Floating-point digital signal processing has become a constant requirement for precision technology, often in applications requiring high accuracy in areas such as aviation, industrial machinery, a...[Details]
Abstract: In order to generate a stable excitation signal, the design of a digital frequency synthesizer is implemented on FPGA using Verilog hardware language. The design includes accumulator, wav...[Details]
In public places such as schools, government agencies, factories and mines, as well as public corridors in residential areas, the phenomenon of long-burning lights is very common, which causes a h...[Details]
1 Introduction
Solar street lights are mainly composed of four parts: solar photovoltaic cell components, batteries, charge and discharge controllers, and lighting fixtures. The bo...[Details]
We know that microcontroller development tools generally include real-time online emulators and programmers. Among them, online emulators are very good tools, but they are also more expensive...[Details]
1 Introduction
There have been many studies on the detection and protection of power grid short circuit and line fault. The short circuit, overload and overvoltage protectors on the market have ...[Details]
This controller uses PIC16C54 single-chip microcomputer as the controller, and it is very easy to use: just connect a telephone line to the loudspeaker through the controller, and you can rem...[Details]
Overview
In spectral measurement, photomultiplier tubes (PMT) and charge-coupled devices (CCD) are often used as photoelectric converters. PMT is used in slow-changing, high-precision spectral...[Details]
Single-chip microcomputers are widely used because of their small size, powerful functions and low price. This article introduces the method of designing a micro electronic piano using the AT89C51 sin...[Details]
Printed circuit boards ( PCBs
)
are used in most electrical products
. If a PCB has low
insulation resistance
(IR), the performance of the circuits on the PCB will be greatly reduced...[Details]
Since the late 1990s, with the demand for higher system efficiency and lower power consumption, the technological update of telecommunications and data communication equipment has promoted the deve...[Details]
Introduction
Nowadays, people pay more and more attention to the security alarm system, and people have higher and higher requirements for the functions and performance of the alarm. This paper prop...[Details]
With the rapid development of cities and the improvement of citizens' living standards, the number of various vehicles in cities is growing, and the demand for parking spaces in major commercial an...[Details]
Embedded System
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