参数资料
型号: XR88C681J-F
厂商: Exar Corporation
文件页数: 57/101页
文件大小: 0K
描述: IC UART CMOS DUAL 44PLCC
标准包装: 27
特点: *
通道数: 2,DUART
FIFO's: 1 字节,3 字节
电源电压: 4.75 V ~ 5.25 V
带并行端口:
带CMOS:
安装类型: 表面贴装
封装/外壳: 44-LCC(J 形引线)
供应商设备封装: 44-PLCC(16.59x16.59)
包装: 管件
其它名称: 1016-1329
XR88C681
59
Rev. 2.11
In general the bit-error-rate, for this “uncorrected” system
is a function of the timing differences between the TX and
RX local clock signals. However, in order to correct for
Receiver Drift and to minimize the BER during serial data
transmission, many UARTs in the market place, employ
Receiver Oversampling of the START bit. When this
feature is employed, the Receiver, upon detection of the
START bit, will begin oversampling this START bit by
some integer factor. Typically, for most present day
UARTs, this over-sample factor is 16. (The XR88C681
device also accommodates 16X receiver oversampling of
the START bit). Therefore, in these devices, when the
Receiver detects the occurrence of a START bit, it (the
Receiver) will begin oversampling this START bit by a
factor of 16. However, after 7 16X clock periods has
elapsed, the receiver will assume this point (within the
START bit) to be the mid point of the bit period, and will
cease oversampling of the START bit and of the
subsequent data. From this point, through the end of the
character, the Receiver will sample the serial data stream
at the 1X rate. Stated another way, once the Receiver has
reached, what it believes to be the mid-point of the START
bit, the receiver will, from that point, begin sampling the
serial data at 1-bit period interval (see
Figure 32). After
the Receiver has received the STOP bit, it will await the
occurrence of the START bit. Once the START bit has
been detected, this oversampling procedure is repeated.
7- 16X clock
periods
Chosen as
the Midpoint
of the Bit
1 Bit Period
Figure 32. The Typical Sampling Pattern of Each Receiver Within the XR88C681 Device.
相关PDF资料
PDF描述
ST16C552AIJ68-F IC UART FIFO 16B DUAL 68PLCC
MS27474T10A98P CONN RCPT 6POS JAM NUT W/PINS
XR88C192IV-F IC UART FIFO DUAL 44LQFP
MS27484T8F35PA CONN PLUG 6POS STRAIGHT W/PINS
ST16C2550IJ44-F IC UART FIFO 16B DUAL 44PLCC
相关代理商/技术参数
参数描述
XR88C681JTR-F 功能描述:UART 接口集成电路 Dual Channel UART RoHS:否 制造商:Texas Instruments 通道数量:2 数据速率:3 Mbps 电源电压-最大:3.6 V 电源电压-最小:2.7 V 电源电流:20 mA 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:LQFP-48 封装:Reel
XR88C681MN-S0968 制造商:Exar Corporation 功能描述:
XR88C681N/40 制造商:EXAR 制造商全称:EXAR 功能描述:CMOS DUAL CHANNEL UART (DUART)
XR88C681P/28 制造商:Exar Corporation 功能描述:
XR88C681P/28-F 功能描述:UART 接口集成电路 Dual Channel UART RoHS:否 制造商:Texas Instruments 通道数量:2 数据速率:3 Mbps 电源电压-最大:3.6 V 电源电压-最小:2.7 V 电源电流:20 mA 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:LQFP-48 封装:Reel