参数资料
型号: DS21FT40
厂商: DALLAS SEMICONDUCTOR
元件分类: Digital Transmission Controller
英文描述: DATACOM, FRAMER, PBGA300
封装: BGA-300
文件页数: 12/87页
文件大小: 386K
代理商: DS21FT40
DS21FT40
2 of 87
dual two-frame elastic stores contained in each of the four framers can be independently enabled and
disabled as required. The device fully meets all of the latest E1 specifications including CCITT/ITU
G.704, G.706, G.962, and I.431 as well as ETS 300 011 and ETS 300 233.
Functional Description
The receive side in each framer locates FAS frame and CRC and CAS multiframe boundaries as well as
detects incoming alarms including, carrier loss, loss of synchronization, AIS and Remote Alarm. If
needed, the receive side elastic store can be enabled in order to absorb the phase and frequency
differences between the recovered E1 data stream and an asynchronous backplane clock which is
provided at the RSYSCLK input. The clock applied at the RSYSCLK input can be either a 2.048 MHz
clock or a 1.544 MHz clock. The RSYSCLK can be a burst clock with speeds up to 8.192 MHz.
The transmit side in each
framer is totally independent from the receive side in both the clock
requirements and characteristics. Data off of a backplane can be passed through a transmit side elastic
store if necessary. The transmit formatter will provide the necessary frame/multiframe data overhead for
E1 transmission.
Reader’s Note: This data sheet assumes a particular nomenclature of the E1 operating environment. In
each 125 us frame, there are 32 8–bit timeslots numbered 0 to 31. Timeslot 0 is transmitted first and
received first. These 32 timeslots are also referred to as channels with a numbering scheme of 1 to 32.
Timeslot 0 is identical to channel 1, timeslot 1 is identical to Channel 2, and so on. Each timeslot (or
channel) is made up of 8 bits which are numbered 1 to 8. Bit number 1 is the MSB and is transmitted
first.
Bit number 8 is the LSB and is transmitted last.
Throughout this data sheet, the following
abbreviations will be used:
FAS
Frame Alignment Signal
CAS
Channel Associated Signaling
MF
Multiframe
Si
International bits
CRC4
Cyclical Redundancy Check
CCS
Common Channel Signaling
Sa
Additional bits
E-bit
CRC4 Error Bits
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相关代理商/技术参数
参数描述
DS21FT40N 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述:
DS21FT42 功能描述:网络控制器与处理器 IC 4x4 16/4x3 12 Chnl T1/T1 Framer RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
DS21FT42N 功能描述:网络控制器与处理器 IC 4x4 16/4x3 12 Chnl T1/T1 Framer RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
DS21FT44 功能描述:网络控制器与处理器 IC RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray
DS21FT44+ 功能描述:网络控制器与处理器 IC 4X3 E1 Framer E1 Framer E1 Framer RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流(最大值):595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray