Kan Kaili, Institute of Information Industry Policy and Development, Beijing University of Posts and Telecommunications Original title: 3G and the future of telecommunications industry The key to ...
I use TL494 to generate PWM, but the high and low levels of the output PWM have problems. The high level is 5V, but the low level is not 0V. The output low level is about 700mV. This forces me to add ...
Input 24V AC from output terminal 1; pass through the diode; then output 4MA from output terminal 2; now I don't know what the LM2902 op amp and the transistor inside are used for; please give me some...
I recently started working on DM9000 and needed a TCP data receiving program. However, when connecting, the teacher made an error. I always felt that the program was wrong, but I didn't know where it ...
Remote keyless entry (RKE) systems have become popular with users, with more than 80% of new cars in North America and more than 70% in Europe equipped with RKE systems. In addition to the obvious ...[Details]
With the rapid development of urban economy, elevators are increasingly used as a vertical transportation tool. However, elevator fault detection and maintenance, especially the role of elevator remot...[Details]
LED is the abbreviation of light emitting diode, which is an electric light source made of semiconductor technology. The core part of LED is a chip composed of P-type semiconductor and N-type semi...[Details]
In recent years, with the rapid development of the information industry, dot matrix LED display screens have been widely used in various advertising and information display systems such as the fina...[Details]
As a simple and practical input device, buttons have been used in various microcontroller application systems and are ubiquitous. However, the buttons used in different practical occasions are also...[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]
Today, the value of electronic components in cars accounts for 15-20% of the total vehicle. In the future, this proportion may be as high as 30-40% as more safety electronics, fuel consumption and ...[Details]
Motors are important products that convert electrical energy into mechanical energy to achieve automation, and they are widely used in industrial control, medical electronics, white a...[Details]
It is well known to automotive suppliers that automakers are demanding more from their supply base. For connector suppliers, this means stricter requirements for product performance, stability and ...[Details]
The era of mobile access to the Internet has arrived, and it will rapidly change the business and infrastructure needs of mobile operators under a whole new trend of requirements. We need 4G LTE to...[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]
With the continuous advancement of various technologies in the field of measurement and control, the baseband subsystem of general measurement and control equipment has entered the fourth generation o...[Details]
Abstract: Based on the ZigBee parking lot SMS car search system, the location of the vehicle in the parking lot is sent to the owner through SMS, which is convenient for the owner to quickly find ...[Details]
Among the uses of electrical energy, lighting accounts for a considerable proportion. Compared with the earlier ordinary incandescent lamps, the fluorescent lamps and energy-saving lamps we commonl...[Details]
Movpower is a portable power bank. It can charge most mobile phones and digital products, such as digital cameras, PDAs, and mobile phones such as Apple, iPod, Blackberry, Motorola, Samsung, Nokia,...[Details]