您的位置：维库电子市场网 > Datasheet > DS26502
DS26502数据手册封面

DS26502 Datasheet

  • DS26502

  • T1/E1/J1/64KCC BITS单元

  • 1043.62KB

  • 125页

  • MAXIM   MAXIM

阅览下载 纠错 0

扫码查看芯片数据手册

上传产品规格书

PDF预览

DS26502 T1/E1/J1/64KCC BITS Element
The transmit line drive has two modes of operation: fixed gain or automatic gain. In the fixed gain mode,
the transmitter outputs a fixed current into the network load to achieve a nominal pulse amplitude. In the
automatic gain mode, the transmitter adjusts its output level to compensate for slight variances in the
network load. See the
Transmit Line Build-Out Control (TLBC)
register for details.
13.3.1 Transmit Short-Circuit Detector/Limiter
The DS26502 has an automatic short-circuit limiter that limits the source current to 50mA (rms) into a
1W load. This feature can be disabled by setting the SCLD bit (LIC2.1) = 1. TCLE (SR1.2) provides a
real-time indication of when the current limiter is activated. If the current limiter is disabled, TCLE will
indicate that a short-circuit condition exist. Status Register SR1.2 provides a latched version of the
information, which can be used to activate an interrupt when enable via the IMR1 register. When set low,
the TPD bit (LIC1.0) will power-down the transmit line driver and tri-state the TTIP and TRING pins.
13.3.2 Transmit Open-Circuit Detector
The DS26502 can also detect when the TTIP or TRING outputs are open circuited. TOCD (SR1.1) will
provide a real-time indication of when an open circuit is detected. SR1 provides a latched version of the
information (SR1.1), which can be used to activate an interrupt when enable via the IMR1 register.
13.3.3 Transmit BPV Error Insertion
When IBPV (LIC2.5) is transitioned from a zero to a one, the device waits for the next occurrence of
three consecutive ones to insert a BPV. IBPV must be cleared and set again for another BPV error
insertion.
13.3.4 Transmit G.703 Section 10 Synchronization Signal (E1 Mode)
The DS26502 can transmit the 2.048MHz square-wave synchronization clock. To transmit the 2.048MHz
clock, when in E1 mode, set the mode configuration bits in the Mode Configuration Register (MCREG).
13.4 MCLK Pre-Scaler
A 16.384MHz, 8.192MHz, 4.096MHz, 2.048MHz, or 1.544MHz clock must be applied at MCLK. ITU
specification G.703 requires an accuracy of 卤50ppm for both T1 and E1. TR62411 and ANSI specs require
an accuracy of 卤32ppm for T1 interfaces. A prescaler will divide the 16MHz, 8MHz, or 4MHz clock down to
2.048MHz. There is a PLL for the jitter attenuator that will convert the 2.048MHz clock to a 1.544MHz rate
for T1 applications. Setting JACKS (LIC2.3) to a logic 0 bypasses this PLL.
13.5 Jitter Attenuator
The jitter attenuator is only available in T1 and E1 modes. The DS26502鈥檚 jitter attenuator can be set to a
depth of either 32 bits or 128 bits via the JABDS bit (LIC1.2). The 128-bit mode is used in applications
where large excursions of wander are expected. The 32-bit mode is used in delay-sensitive applications.
The characteristics of the attenuation are shown in
Figure 13-10
and
Figure 13-11.
The jitter attenuator
can be placed in either the receive path or the transmit path by appropriately setting or clearing the JAS
bit (LIC1.3). If the part is configured for hardware mode and the jitter attenuator is enabled, it will
automatically be placed in the receive path. The jitter attenuator can also be disabled (in effect, removed)
by setting the DJA bit (LIC1.1). Either the recovered clock from the clock/data recovery block or the
clock applied at the TCLK pin is adjusted to create a smooth jitter-free clock that is used to clock data out
of the jitter attenuator FIFO. It is acceptable to provide a gapped/bursty clock at the TCLK pin if the
jitter attenuator is placed on the transmit side. If the incoming jitter exceeds either 120 UI
P-P
(buffer
depth is 128 bits) or 28 UI
P-P
(buffer depth is 32 bits), then the DS26502 will divide the internal nominal
79 of 124

DS26502 PDF文件相关型号

DS26502LN

DS26502相关型号PDF文件下载

您可能感兴趣的PDF文件资料

热门IC型号推荐

©2024 维库电子市场网（www.dzsc.com）　备案号：浙B2-20050339-1 经营许可证：浙B2-20210386版权声明
买家服务热线：0571-85317607 | 买家服务部QQ： QQ:1609526468
卖家服务热线：0571-85317607 | 卖家服务部QQ： QQ:331652727

扫码下载APP，
一键连接广大的电子世界。

在线人工客服

买家服务：
卖家服务：

0571-85317607

客服在线时间周一至周五
9:00-17:30

关注官方微信号，
第一时间获取资讯。

建议反馈
返回顶部

建议反馈

联系人：

联系方式：

按住滑块，拖拽到最右边
>>
感谢您向阿库提出的宝贵意见，您的参与是维库提升服务的动力！意见一经采纳，将有感恩红包奉上哦！

PDF纠错X

投诉电话：0571-85317607 投诉QQ：

如选匿名将无法为您反馈投诉结果，建议实名投诉！