Rapoo Vt350 Dual-mode Game Mouse Evaluation Continues the Design

Analysis of Design Scheme of Portable B-ultrasound Power Supply

Why Is Arc Suppression Coil Called Arc Suppression Coil?

What Does Integrated Gate Commutated Thyristor (IGCT) Mean

What does integrated gate commutated thyristor (IGCT) meanIntegrated Gate Commutated Thyristors IGCT (Integrated Gate Commutated Thyristors) is a new type of power semiconductor device used in giant power electronic devices published in 1996. IGCT is a new high-power semiconductor switching device based on GTO structure, using integrated gate structure for gate hard drive, using buffer layer structure and anode transparent emitter technology. It has the on state characteristics of thyristor and the switching characteristics of transistor. Due to the buffer structure and shallow emitter technology, the dynamic loss is reduced by about 50%. In addition, this kind of device also integrates a freewheeling diode with good dynamic characteristics on one chip, so as to organically combine the low on-state voltage drop of thyristor, high blocking voltage and the stable switching characteristics of transistor in its unique wayIGCT makes great progress in power, reliability, switching speed, efficiency, cost, weight and volume, and brings a new leap to the complete set of power electronics devices. IGCT integrates GTO chip with anti parallel diode and gate drive circuit, and then connects with its gate driver in a low inductance way. It combines the advantages of stable turn-off ability of transistor and low on state loss of thyristor, gives full play to the performance of thyristor in the on stage, and presents the characteristics of transistor in the off stage. IGCT has the characteristics of large current, high voltage, high switching frequency, high reliability, compact structure, low loss, low manufacturing cost and high yield. GTO with thyristor technology is a common high-power switching device. It has higher performance in cut-off voltage than IGBT with transistor technology. However, the widely used standard GTO driving technology causes uneven turn-on and turn-off process, requiring high-cost DV / dt and di / dt absorption circuits and high-power gate driving units, resulting in reduced reliability and high price, It is also not conducive to series connection. However, before the maturity of high-power MCT technology, IGCT has become the preferred scheme of high-voltage, high-power and low-frequency AC.The figure below shows the outline of asymmetric IGCTIGCT is similar to GTO. It is also a four layer three terminal device. The GCT is composed of thousands of GCTs. The anode and gate are shared, while the cathode are connected in parallel. The important difference from GTO is that there is a buffer layer inside the IGCT anode, and the transparent (permeable) anode is used to replace the short-circuit anode of GTO. The on mechanism is exactly the same as that of GTO, but the off mechanism is completely different from that of GTO. During the off process of IGCT, GCT can instantly change from on to blocking state, become a PNP transistor and then turn off, so it has no external Du / dt limit; The GTO must be converted through an intermediate unstable state that is neither on nor off (i.e. "GTO area"), so GTO needs a large absorption circuit to suppress the change rate Du / dt of the re applied voltage. The equivalent circuit of IGCT in blocking state can be considered as the series connection of a base open circuit, low gain PNP transistor and gate power supply.The IGCT trigger power is small. The trigger and state monitoring circuit and the IGCT tube core can be made into a whole, and the trigger signal and working state signal can be input and output through two optical fibers. IGCT integrates the advantages of GTO technology and modern power transistor IGBT. Using the key technology that high-power shutdown devices can be simply and reliably connected in series, IGCT has no real rival in the medium and high voltage field and the high-power application field with power of 0.5mva 100mva.The following table shows the performance comparison of IGBT, GTO and IGCT power devices:The advantages of low loss and fast switching of IGCT ensure that it can be reliably and efficiently used in 300 KVA 10MVA converter without series or parallel. When connected in series, the inverter power can be extended to 100mva. Although the high-power IGBT module has some excellent characteristics, such as active control of di / dt and DV / DT, active clamping, easy to realize short-circuit current protection and active protection, etc. However, due to the disadvantages of high conduction loss, open circuit after damage and no long-term reliable operation data, the practical application of high-power IGBT module in high-power low-frequency converter is limited. Therefore, IGCT will become the preferred power device of high power and high voltage frequency converter.

Ces2017 ASUS Expands the National Product Line of Players: Launch Peripherals Such As Microphone / G

At CES 2017, we saw countless game peripherals, and ASUS once again expanded its "player country" (Rog) product line, and launched peripherals such as microphone, game mouse and high-end router. First, let's introduce the Rog Strix Magnus microphone, which is specially built for the live streaming media market and has a compact shape. In terms of function, the microphone includes three groups of studio level capacitive pickups, and can reduce the ambient sound.Rog Strix Magnus microphoneIt is worth mentioning that the microphone can also be used as an external USB hub and supports aura RGB lighting effect.Rog gladius II game mouseRog gladius II is an optical mouse equipped with aura sync RGB light effect and OMRON button. Users can adjust DPI in real time through two buttons (one button is behind the wheel and the other is at the thumb position, so as to select the best accuracy when aiming).ASUS claims that its buttons can withstand 50 million clicks and support easy replacement. This can not only prolong the service life of the device, but also enable players to adjust the feel on demand.New Rog Strix evolve mouseThe top cover of the new Rog Strix evolve mouse is divided into four pieces, which is very in line with the ergonomic design. Left handed players will appreciate this replaceable top cover design.In addition, ASUS also launched a new Rog Strix impact mouse, which adopts a lightweight design, which is suitable for users who like dexterous, accurate and simple control.It should be noted that both Strix evolve and Strix impact support aura sync RGB light control and OMRON buttons.Rog gx970 mouseThe mouse adopts the design of switchable side panel, and the user can choose between two side keys and ten side keys (these two side plates are provided in the packaging box at the same time). Through the supporting software, users can also specify functions for keys and store them in onboard ROM.The Rog gx970 mouse also supports counterweight adjustment, with a maximum tracking speed of 12000 DPI.Rog rapture gt-ac5300 wireless routerFinally, Rog rapture gt-ac5300 tri band wireless router is introduced. In addition, it also provides 8 & Themes; Gigabit Ethernet port.The route adopts an unspecified 1.8GHz quad core processor, and the gaming center software can be used as a good tool to quickly monitor and adjust network traffic (such as optimizing Ping value for popular games).In addition, ASUS also launched a gt-ac5300 wireless router, which provides two "game specific" LAN ports and supports functions such as GameBoost (which can optimize the network communication of the game).

How to Use Excel to Improve Your Work Efficiency 10 Basic Excel Skills Let You Get Twice the Result

Excel is the most magical and important software in MS office series. Stop foolishly clicking around with the mouse! Use these 10 basic skills to improve work efficiency and get twice the result with half the effort1. "Ctrl PgDn / PgUp" conversion worksheet2. Use "Ctrl directional character" to quickly convert cellsOf course, you can just press the direction key and move it grid by grid. But if you want to quickly convert cells, long press "Ctrl" before pressing the direction key, and you can achieve the effect of "key step like flying" in an instant.3. Skillfully use the "shift" key to select dataUse "Ctrl Shift" to select cells vertically and horizontally, so as to select the area you want.4. Double click auto fill dataTo automatically fill in the same column with functions, don't long press the mouse and try to pull down to the last column - what if your table has hundreds of rows? Double click the lower right cross of the calculated cell to easily fill in the complete column of data.5. Let the three shortcut keys quickly unify the data formatDo you want the data to appear to two decimal places? Use Ctrl Shift!.How much is the unit? Use Ctrl Shift $.What percentage do you want? Use Ctrl Shift%.Isn't it tired to click the mouse so many times? Use these three shortcut keys to realize the uniform format of the speed of light, and the latter two should be particularly easy to remember.6. Lock the cell with F4When filling data according to functions in Excel, sometimes you want the cells you reference to change when they drop down, and sometimes you don't think so. When you want to "absolute reference" - that is, lock the cell, you must add a $sign before the row and column. Want to type these dollar symbols manually? It's crazy... How much time will it waste, you know? In fact, there is a simple technique, that is, after you select the cell, press F4 to enter the dollar symbol and lock it; If you continue to press F4, you will cycle back one by one: Lock cells, lock numbers, lock uppercase letters, and unlock.7. Summarize statistics with countif and SUMIFCountif is a function algorithm that counts the number of cells that meet established conditions within a specific range. The first parameter is the range you want to count; The second parameter is your condition. For example: = countif (A1: a10,1), that is, within the range of A1: A10, the cell content is 1 number.COUNTIF(range,criteria)The SUMIF function is used to sum several cells, ranges, or references based on specified conditions. Below is the total number of views we are calculating for each author. In terms of scope, the format of the author's name is inconsistent, but the total number is the same. Column B corresponds to the name of the corresponding author, and column e corresponds to the number of views of each author's work.SUMIF(range,criteria,sum range)8. Use vlookup to find the data you wantVlookup is a search function by column, and finally returns the value corresponding to the required query column order of the column. Here we can see a data table. The first column is the ranking of law schools. We can use vlookup to create a query of the top five schools.VLOOKUP(lookup value,data range,column number,type)The first parameter needs to enter the value to find. Here we use the number of rankings we need. The second parameter here, enter the region we want to find (absolute reference). For the third parameter, you need to enter the number of columns of the returned data in the search area. For the fourth parameter, because we want to find it accurately, enter "false" or "0".9. Merge cells with "&"We now have a column of last names and a column of names. We can use the "&" symbol to create a column of data that combines last names and first names. In Excel, "&" refers to merging two or more texts. Don't forget to type a space between your last name and first name. Your function should look like this format = [first name] & "& [last name].10. Generate random number with rand functionYou can use the rand() function to generate a single random number, which is less than 1 but greater than or equal to 0. Just leave the parentheses empty without typing any parameters. The new random number will be regenerated with the update of the workbook. You can also press F9 to recalculate the worksheet to update the random number, but remember to be careful when operating.RAND()

Speaker Unit for Home Theater Set

Speaker unit for home theater set Speaker unit refers to the situation of speakers (commonly known as speakers) used in the set speaker of home theater. It usually refers to the size, shape and material of speakers, which mainly determine the characteristics of speakers.Most of the structural forms of subwoofer are cone basin type, and a few are flat plate type. There are many kinds of subwoofer diaphragm, including aluminum alloy diaphragm, aluminum magnesium alloy diaphragm, ceramic diaphragm, carbon fiber diaphragm, bulletproof cloth diaphragm, glass fiber diaphragm, propylene diaphragm, paper diaphragm, etc. Bass unit, which determines the sound characteristics of the speaker, is relatively important to choose. The bass unit with aluminum alloy diaphragm and glass fiber diaphragm generally has small caliber and large bearing power, while the bass unit with reinforced paper basin and glass fiber diaphragm has accurate timbre and good overall balance when replaying music. The paper basin has natural sound, low cost, good rigidity, light material and high sensitivity. The disadvantages are poor moisture resistance and difficult to control the consistency during manufacturing. However, the paper basin is made everywhere in the top hifi system because the sound output is very average and the reducibility is good. Bulletproof cloth, with wide frequency response and low distortion, is the first choice for those who love strong bass. Its disadvantages are high cost, complex production process, low sensitivity and poor light music effect. The wool woven basin has a soft texture. It performs very well for soft music and light music, but the bass effect is poor and lacks strength and shock. PP (polypropylene) basin, which is widely popular in high-grade speakers, has good consistency, low distortion and commendable performance in all aspects. In addition, fiber diaphragm and composite diaphragm are rarely used in popular speakers due to their high price.Generally speaking, as long as the frequency response curve of the mid-range loudspeaker is flat, the effective frequency response range is greater than the width of the playback frequency band it undertakes in the system, and the impedance is consistent with the sensitivity and low-frequency unit. Alto units generally have cone basin and ball top. But its size and power are larger than the tweeter and suitable for playing medium audio. The diaphragms of the Alto unit are mainly soft materials such as paper basin and silk film, and occasionally there are a small amount of alloy ball top diaphragms.The function of high-frequency loudspeaker in speaker is to replay various high-frequency signals, and its working frequency is generally above 2K. The overall requirement for high-frequency loudspeaker is that it can have flat frequency response, high-frequency playback upper limit as much as possible and certain power bearing capacity to meet the requirements in the effective working frequency band. Its structural forms mainly include horn type, cone basin type, ball top type and aluminum belt type. At present, the most common domestic speaker and small monitoring speaker is ball top type. The ball top tweeter is divided into hard ball top and soft ball top from the material. The diaphragm materials of hard top treble include aluminum alloy, titanium alloy, magnesium alloy, titanium alloy composite film, glass film, diamond film and so on. The treble played back by the hard top treble unit has bright timbre and metal feeling. It is suitable for playing pop music, film music and effect music. The production of excellent aluminum alloy and titanium alloy composite film dome tweeter can also better express classical music and human voice. The vibrating film materials of the soft ball top tweeter are silk film, silk thread film, rubber film and bulletproof cloth film. The soft dome tweeter unit is flexible and relaxed when replaying music, and has good natural expressiveness. It is particularly handy when performing classical music, human voice and other music with standard listening concepts. In recent years, the playback upper limit frequency of silk film and silk film ball tenor has reached 40KHz. Theoretically, the upper limit frequency of tweeter unit should at least reach 20kHz, the higher the better. However, the unit with excellent high frequency upper limit is also more expensive.Naturally, the larger the speaker size, the better. Large caliber bass speakers can perform better in the low-frequency part, which can be selected in the purchase. Most of the subwoofers in ordinary home cinemas are between 5 and 12 inches. The speakers made of high-performance speakers also mean lower transient distortion and better sound quality.

How the Mouse Works

How the mouse worksWorking mode refers to the working principle or mode adopted by the mouse. The common working modes of mouse include roller type and photoelectric type.Roller type Roller type is the most common mouse. Its biggest feature in appearance is that there is a positioning roller in the groove at the bottom to move the cursor. According to the working principle, the roller mouse can be divided into the first generation of pure mechanical type and the second generation of optomechanical type (hereinafter referred to as optomechanical type). (1) Pure mechanical Pure mechanical mouse is rarely seen in the world now. There is a rolling ball at the bottom of it. When the mouse is pushed, the rolling ball will constantly touch the small roller next to it to produce pulses of different intensities. Through this chain effect, the computer can calculate the correct position of the cursor. (2) Optical mechanical type This is commonly referred to as the mechanical mouse, which is a combination of photoelectric and mechanical mouse. Its principle is that there are two mutually perpendicular transmission shafts close to the rolling rubber ball, and there is a grating wheel on the shaft. The two sides of the grating wheel correspond to light-emitting diodes and photosensitive triodes. When the mouse moves, the rubber ball drives the two transmission shafts to rotate, and the time grid wheel is also rotating. The photosensitive triode is intermittently blocked by the grating wheel when receiving the light emitted by the light-emitting diode, so as to generate pulse signals, which are received by the CPU after being processed by the chip inside the mouse. The number and frequency of signals correspond to the distance and speed on the screen.Photoelectric type Photoelectric mouse products can be divided into two generations according to their age and technology. Their common feature is that there is no mouse ball that must be used for mechanical mouse. The first generation of photoelectric mouse judged the signal by the light interrupter. The most remarkable feature is that a special reflector needs to be used as the pad when the mouse moves. The main feature of this pad is the tiny black and white dots. The reason is that at the bottom of the photoelectric mouse, there is a light-emitting diode and two mutually perpendicular photosensitive tubes. When the light-emitting diode irradiates the white spot and black spot, it will produce two states of refraction and non refraction, and the photosensitive tube will produce corresponding signals after processing these two states. So that the computer can respond. Once it leaves the pad, the photoelectric mouse can't be used. At present, the photoelectric mouse products on the market are the second generation of photoelectric mouse. The principle of the second generation photoelectric mouse is actually very simple: it uses the optical eye technology, which is a digital photoelectric technology. Compared with the previous mechanical mouse, it is a completely new technical breakthrough.The photoelectric sensing device transmits and receives every second to realize accurate and fast positioning and command transmission. Another advantage is that the optical eye technology abandons the shackles of the previous generation of optical mouse, which requires a special mouse board, and can be used on any non reflective and opaque object surface. The biggest advantage of using it is that it does not need to clean the mouse ball as often as the mechanical mouse, and its resolution and refresh rate are much higher than the mechanical mouse. The positioning of high-grade optical mouse is very accurate. Generally speaking, the start of photoelectric mouse is very high, that is to say, most photoelectric mice are ergonomically designed, so that consumers can have a more appropriate reason for consumption.Fingerprint mouse Fingerprint mouse is a special function mouse with fingerprint acquisition and identification functions. It is suitable for individuals, offices, enterprises and other industries and enterprises with high security requirements. Because of its high price, it is not suitable for ordinary individual users.With the popularization of office automation, our daily work can not leave the computer. Each computer user will encrypt their important data and files to protect their own confidentiality or privacy. But this traditional password has obvious disadvantages, that is, the password is easy to be forgotten, the password is easy to be peeped and obtained by those with ulterior motives, the password is easy to be cracked, and so on. To solve this problem, the computer security management system has a new encryption method, fingerprint identification encryption. A fingerprint acquisition sensor is integrated on the fingerprint mouse. Each time the computer is turned on, the user puts a specific finger (generally thumb) on the sensor window, and the computer automatically scans it, and then compares it with the fingerprint stored in the system, so that it can be easily and safely connected to the host to start working, so as not to worry about illegal entry of irrelevant personnel. The fingerprint mouse can be used when logging in and restoring screen protection, or when decompressing encrypted files. Its main indicators in terms of security are self rejection rate, others' tolerance rate and fingerprint image transmission rate (this parameter determines the speed of fingerprint acquisition and identification). At present, the mainstream products have reached a very low error rate in this self rejection rate and others' tolerance rate, and the fingerprint image transmission rate can reach more than ten frames per second.

Wireless Tilt Mouse - XBee Demonstration of Accelerometer

1. IntroductionThis document shows how to easily build an interesting pointing device step by step: wireless tilt mouse, that is, you can control the mouse through the on-line tilt board itself and the computer screen cursor. Analog data from three-dimensional accelerometer and two keys are obtained, converted and broadcast by using standard XBee module to transmit ZigBee protocol. At the receiving end, another XBee module is connected to the computer through easyusb module, allowing the two files to be stored in the same interface and communicated?? S, seen as a common mass storage device PC. In practice, there is no need to install any application on the computer: the software, communication with XBee and analog mouse function is the residents' internal easyusb itself, which is automatically recognized by the computer as a USB drive. The accelerometer / transmitter circuit board is powered by AA batteries. The goal of the project is to become an open source hardware / software platform that can accelerate learning about access and use? Data, configure and manage customized XBee module USB peripherals. All hardware?? Schematic diagram and software source code are well annotated with project files. In order to design a fast and easy to build platform, only breakthrough boards and modular components are used. Specific skills such as patch welding and embedded software programming are not necessary.2. Construction steps2.1.1 hardware connection - connect the board: welding wire according to the hardware schematic diagram and wiring diagram. Please note that the XBee modules of the chip antenna should not be welded: they are connected to the appropriate XBee browser regulated socket.2.1.2 Transmitter configuration - insert the XBee module in the slot on the receiver and the USB cable into the PC. The waiting device is automatically installed as a common USB mass storage device.-Copy to USB device XBee_ Config.exe console. Run XBee_ Config.exe console, press t to configure as the transmitter XBee module. Press ESC to exit.-Take off the XBee module from the receiver socket and place it in the transmitter socket. 2.1.3 Receiver configuration - connect the socket on the receiver to another XBee module. Run XBee_ Config.exe console, press R to configure to receive XBee module. Press ESC to exit.-Copy the tiltmouse.exe scheme to the USB device. Wireless mouse transmitter and receiver tilt is complete! In order to use it, just run tiltmouse.exe on the receiver, the transmitter on the console and the battery of the plug. Console, better than analog mouse? In addition to the function, also print the data obtained from each acceleration on the screen? S axis and button.2.2 schematic diagram

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Rapoo Vt350 Dual-mode Game Mouse Evaluation Continues the Design Style of VT Series Cool Technology