The PCA9673 provides general purpose remote I/O expansion for most microcontrollerfamilies via the two-line bidirectional bus (I2C-bus) and is a part of the Fast-mode Plusfamily.The PCA9673 is a drop in upgrade for the PCF8575 providing higher Fast-mode Plus(Fm+) I2C-bus speeds (1 MHz versus 400 kHz) so that the output can support PWMdimming of LEDs, higher I2C-bus drive (30 mA versus 3 mA) so that many more devicescan be on the bus without the need for bus buffers, higher total package sink capacity(400 mA versus 100 mA) that supports having all 25 mA LEDs on at the same time andmore device addresses (16 versus 8) are available to allow many more devices on the buswithout address conflicts.
上传时间: 2013-10-29
上传用户:wkchong
The PCA9674/74A is a drop-in upgrade for the PCF8574/74A providing higher Fast-modePlus I2C-bus speeds (1 MHz versus 400 kHz) so that the output can support PWMdimming of LEDs, higher I2C-bus drive (30 mA versus 3 mA) so that many more devicescan be on the bus without the need for bus buffers, higher total package sink capacity(200 mA versus 100 mA) that supports having all LEDs on at the same time and moredevice addresses (64 versus 8) are available to allow many more devices on the buswithout address conflicts.
上传时间: 2013-10-22
上传用户:wwwwwen5
The TL2575 and TL2575HV represent superior alternatives to popular three-terminal linear regulators. Due totheir high efficiency, the devices significantly reduce the size of the heatsink and, in many cases, no heatsink isrequired. Optimized for use with standard series of inductors available from several different manufacturers, theTL2575 and TL2575HV greatly simplify the design of switch-mode power supplies by requiring a minimaladdition of only four to six external components for operation.
标签: STEP-DOWN SWITCHING SIMPLE 1A
上传时间: 2013-11-20
上传用户:jelenecheung
The C500 microcontroller family usually provides only one on-chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.
标签: synchronous Emulating serial
上传时间: 2014-01-31
上传用户:z1191176801
Presents short and simple I2C software routines that support onlyslave (rather than master or master & slave) operation and an ASMdemonstration program. The slave-only software in this app notecomplements the master mode software presented in AN464, Usingthe 87LPC76X microcontroller as an I2C bus master.
上传时间: 2013-11-22
上传用户:1039312764
Express Mode uses an 8-bit wide bus path for fast configuration of Xilinx FPGAs. Thisapplication note provides information on how to perform Express configuration specifically forthe Spartan™-XL family. The Express mode signals and their associated timing are defined.The steps of Express configuration are described in detail, followed by detailed instructions thatshow how to implement the configuration circui
标签: Spartan-XL Express XAPP FPGA
上传时间: 2014-12-28
上传用户:hewenzhi
为了在CDMA系统中更好地应用QDPSK数字调制方式,在分析四相相对移相(QDPSK)信号调制解调原理的基础上,设计了一种QDPSK调制解调电路,它包括串并转换、差分编码、四相载波产生和选相、相干解调、差分译码和并串转换电路。在MAX+PLUSⅡ软件平台上,进行了编译和波形仿真。综合后下载到复杂可编程逻辑器件EPM7128SLC84-15中,测试结果表明,调制电路能正确选相,解调电路输出数据与QDPSK调制输入数据完全一致,达到了预期的设计要求。 Abstract: In order to realize the better application of digital modulation mode QDPSK in the CDMA system, a sort of QDPSK modulation-demodulation circuit was designed based on the analysis of QDPSK signal modulation-demodulation principles. It included serial/parallel conversion circuit, differential encoding circuit, four-phase carrier wave produced and phase chosen circuit, coherent demodulation circuit, difference decoding circuit and parallel/serial conversion circuit. And it was compiled and simulated on the MAX+PLUSⅡ software platform,and downloaded into the CPLD of EPM7128SLC84-15.The test result shows that the modulation circuit can exactly choose the phase,and the output data of the demodulator circuit is the same as the input data of the QDPSK modulate. The circuit achieves the prospective requirement of the design.
上传时间: 2014-01-13
上传用户:qoovoop
a8259 可编程中断控制 altera提供 The a8259 is designed to simplify the implementation of the interrupt interface in 8088 and 8086 based microcomputer systems. The device is known as a programmable interrupt controller. The a8259 receives and prioritizes up to 8 interrupts, and in the cascade mode, this can be expanded up to 64 interrupts. An asynchronous reset and a clock input have been added to improve operation and reliability.
上传时间: 2014-11-29
上传用户:zhyiroy
通过分析流水线结构和单周期结构的片上网络路由器,提出了一种低延时片上网络路由器的设计,并在SMIC 0.13um Mixed-signal/RF 1.2V/3.3V工艺进行流片验证。芯片测试结果表明,该路由器可以在300 MHz时钟频率下工作,并且在相同负载下,与其他结构的路由器相比较,其能够在较低延时下完成数据包传送功能。
上传时间: 2014-12-28
上传用户:bakdesec
This application note describes a reference system which illustrates how to build an embeddedPowerPC® system using the Xilinx 1-Gigabit Ethernet Media Access Controller processor core.This system has the PLB_Gemac configured to use Scatter/Gather Direct Memory Access andthe Serializer/Deserializer (SerDes) interface. This application note describes how to set up thespecific clocking structure required for the SerDes interface and the constraints to be added tothe UCF file. This reference system is complete with a standalone software application to testsome of the main features of this core, including access to registers, DMA capabilities, transmitand receive in loopback mode. This reference system is targeted for the ML300 evaluationboard.
上传时间: 2013-11-01
上传用户:truth12