The AP2406 is a 1.5Mhz constant frequency, slope compensated current mode PWM step-down converter. The device integrates a main switch and a synchronous rectifier for high efficiency without an external Schottky diode. It is ideal for powering portable equipment that runs from a single cell lithium-Ion (Li+) battery. The AP2406 can supply 600mA of load current from a 2.5V to 5.5V input voltage. The output voltage can be regulated as low as 0.6V. The AP2406 can also run at 100% duty cycle for low dropout operation, extending battery life in portable system. Idle mode operation at light loads provides very low output ripple voltage for noise sensitive applications. The AP2406 is offered in a low profile (1mm) 5-pin, thin SOT package, and is available in an adjustable version and fixed output voltage of 1.2V, 1.5V and 1.8V
上传时间: 2017-02-23
上传用户:w124141
The SP2526A device is a dual +3.0V to +5.5V USB Supervisory Power Control Switch ideal for self-powered and bus-powered Universal Serial Bus (USB) applications. Each switch has low on-resistance (110mΩ typical) and can supply 500mA minimum. The fault currents are limited to 1.0A typical and the flag output pin for each switch is available to indicate fault conditions to the USB controller. The thermal shutdown feature will prevent damage to the device when subjected to excessive current loads. The undervoltage lockout feature will ensure that the device will remain off unless there is a valid input voltage present.
标签: High-Side Switch Power Dual USB
上传时间: 2019-03-06
上传用户:bhitr
在包 hugeinteger 中创建功能类 HugeInteger,该类用来存放和操作一个不超过 40 位的大整数。 (1) 定义一个构造函数,用来对大整数进行初始化。参数为一个字符串。 (2) 定义 input 成员函数,实现大整数的重新赋值。参数为一个字符串,无返回 值。 (3) 定义 output 成员函数,将大整数输出到屏幕上。无参数无返回值。 (4) 定义 add 成员函数,实现两个大整数的加法。参数为一个 HugeInteger 对 象,无返回值,例如: HugeInteger A = new HugeInteger("12345"); HugeInteger B = new HugeInteger("1234"); A.add(B); 此时,A 为 13579,B 为 1234。 (5) 定义 sub 成员函数,实现两个大整数的减法。参数和返回值同 add 函数。 (6) 定义若干大整数关系运算的成员函数,包括 isEqualTo(等于,=)、 isNotEqualTo(不等于,≠)、isGreaterThan(大于,>)、isLessThan(小 于,<)、isGreaterThanOrEqualTo(大于等于,≥)和 isLessThanOrEqualTo (小于等于,≤)。这些函数的参数为一个 HugeInteger 对象,返回值为一个 布尔类型,表示关系运算的结果,例如: HugeInteger A = new HugeInteger("12345"); HugeInteger B = new HugeInteger("1234"); 那么此时 A.isGreaterThan(B)的结果应当为 True,表示 12345>1234。
上传时间: 2019-06-01
上传用户:idealist
High-Speed, Low-Power Dual Operational Amplifier The AD826 features high output current drive capability of 50 mA min per amp, and is able to drive unlimited capacitive loads. With a low power supply current of 15 mA max for both amplifiers, the AD826 is a true general purpose operational amplifier. The AD826 is ideal for power sensitive applications such as video cameras and portable instrumentation. The AD826 can operate from a single +5 V supply, while still achieving 25 MHz of band width. Furthermore the AD826 is fully specified from a single +5 V to ±15 V power supplies. The AD826 excels as an ADC/DAC buffer or active filter in data acquisition systems and achieves a settling time of 70 ns to 0.01%, with a low input offset voltage of 2 mV max. The AD826 is available in small 8-lead plastic mini-DIP and SO packages.
上传时间: 2020-04-19
上传用户:su1254
This book gives a comprehensive overview of the technologies for the advances of mobile radio access networks. The topics covered include linear transmitters, superconducting filters and cryogenic radio frequency (RF) front head, radio over fiber, software radio base stations, mobile terminal positioning, high speed downlink packet access (HSDPA), multiple antenna systems such as smart antennas and multiple input and multiple output (MIMO) systems, orthogonal frequency division multiplexing (OFDM) systems, IP-based radio access networks (RAN), autonomic networks, and ubiquitous networks.
标签: Advances Networks Access Mobile Radio in
上传时间: 2020-05-26
上传用户:shancjb
Employing multiple transmit and receive antennas, namely using multi-input multi-output (MIMO) systems, has proven to be a major breakthrough in providing reliable wireless communication links. Since their invention in the mid-1990s, transmit diversity, achieved through space-time coding, and spatial multiplexing schemes have been the focus of much research in the area of wireless communications.
标签: Communication Systems Coding MIMO for
上传时间: 2020-05-26
上传用户:shancjb
Multiple-Input Multiple-Output (MIMO) systems have recently been the subject of intensive consideration in modem wireless communications as they offer the potential of providing high capacity, thus unleashing a wide range of applications in the wireless domain. The main feature of MIMO systems is the use of space-time processing and Space-Time Codes (STCs). Among a variety of STCs, orthogonal Space-Time Block Codes (STBCs) have a much simpler decoding method, compared to other STCs
标签: Orthogonal Space-Time Processing Complex
上传时间: 2020-05-26
上传用户:shancjb
Multiuser multiple-input-multiple-output (MU- MIMO) systems are known to be hindered by dimensionality loss due to channel state information (CSI) acquisition overhead. In this paper, we investigate user-scheduling in MU-MIMO systems on account of CSI acquisition overhead, where a base station dynamically acquires user channels to avoid choking the system with CSI overhead.
标签: Acquisition Dynamic Channel
上传时间: 2020-05-27
上传用户:shancjb
The writing of this book was prompted by two main developments in wireless communications in the past decade. First is the huge surge of research activities in physical-layer wireless communication theory. While this has been a subject of study since the 60’s, recent developments in the field, such as opportunistic and multi-input multi-output (MIMO) communication techniques, have brought completely new per- spectives on how to communicate over wireless channels.
标签: Communication Fundamentals Wireless of
上传时间: 2020-05-27
上传用户:shancjb
To meet the future demand for huge traffic volume of wireless data service, the research on the fifth generation (5G) mobile communication systems has been undertaken in recent years. It is expected that the spectral and energy efficiencies in 5G mobile communication systems should be ten-fold higher than the ones in the fourth generation (4G) mobile communication systems. Therefore, it is important to further exploit the potential of spatial multiplexing of multiple antennas. In the last twenty years, multiple-input multiple-output (MIMO) antenna techniques have been considered as the key techniques to increase the capacity of wireless communication systems. When a large-scale antenna array (which is also called massive MIMO) is equipped in a base-station, or a large number of distributed antennas (which is also called large-scale distributed MIMO) are deployed, the spectral and energy efficiencies can be further improved by using spatial domain multiple access. This paper provides an overview of massive MIMO and large-scale distributed MIMO systems, including spectral efficiency analysis, channel state information (CSI) acquisition, wireless transmission technology, and resource allocation.
标签: Large-scale Antenna Systems
上传时间: 2020-05-27
上传用户:shancjb