- 您现在的位置：买卖IC网 > PDF目录294843 > ACS8509 ATM/SONET/SDH SUPPORT CIRCUIT, PQFP100 PDF资料下载
参数资料
| 型号： | ACS8509 |
| 元件分类： | 数字传输电路 |
| 英文描述： | ATM/SONET/SDH SUPPORT CIRCUIT, PQFP100 |
| 封装： | LQFP-100 |
| 文件页数： | 5/68页 |
| 文件大小： | 703K |
| 代理商： | ACS8509 |
第1页第2页第3页第4页当前第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页
ADVANCED COMMUNICATIONS
FINAL
DATASHEET
Revision 2.00/January 2006 Semtech Corp.
Page 13
www.semtech.com
ACS8509 SETS
Figure 4 Minimum Input Jitter Tolerance (DS1/E1)
Low Jitter Multiple E1/DS1 Outputs
This feature is activated using the cnfg_control1 register.
This sends a frequency of twice the Dig2 rate (see reg
addr 39h, bits 7:6) to the APLL instead of the normal
77.76 MHz. For this feature to be used, the Dig2 rate
must only be set to 12352 kHz/16384 kHz using the
cnfg_T0_output_frequencies register. The normal OC-3
rate outputs are then replaced with E1/DS1 multiple
rates. The E1(SONET)/DS1(SDH) selection is made in the
same way as for Dig2 using the cnfg_T0_output_enable
register.
Table 11 shows the relationship between primary output
frequencies and the corresponding output in E1/DS1
mode, and from which output they are available.
Output Wander and Jitter
Wander and jitter present on the output clocks are
dependent on:
1. The magnitude of wander and jitter on the selected
input reference clock (in Locked mode).
2. The internal wander and jitter transfer characteristic
(in Locked mode).
3. The jitter on the local oscillator clock.
4. The wander on the local oscillator clock (in Holdover
mode).
Wander and jitter are treated in different ways to reflect
their differing impacts on network design. Jitter is always
strongly attenuated, whilst wander attenuation can be
varied to suit the application and operating state. Wander
and jitter attenuation is performed using a digital phase
locked loop (DPLL) with a programmable bandwidth. This
gives a transfer characteristic of a low pass filter, with a
programmable pole. It is sometimes necessary to change
the filter dynamics to suit particular circumstances - one
example being when locking to a new source, the filter can
be opened up to reduce locking time and can then be
gradually tightened again to remove wander. Since
wander represents a relatively long-term deviation from
the nominal operating frequency, it affects the rate of
supply of data to the network element. Strong wander
attenuation limits the rate of consumption of data to
within a smaller range, so a larger buffer store is required
to prevent data loss. But, since any buffer store potentially
A1
A2
Jitter and Wander Frequency (log scale)
Peak-to-peak Jitter and Wander Amplitude
(log scale)
f1
f2
f3
f4
F8530D_004MINIPJITTOLDS1E1_02
Table 9 Amplitude and Frequency Values for Jitter Tolerance (DS1/E1)
Type
Spec.
Amplitude (UIp-p)Frequency (Hz)
A1
A2
F1
F2
F3
F4
DS1
GR-1244-CORE[19]
5
0.1
10
500
8 k
40 k
E1
ITU G.823[13]
1.5
0.2
20
2.4 k
18 k
100k
相关PDF资料 |
PDF描述 |
|---|---|
| ACS8946T | ATM/SONET/SDH SUPPORT CIRCUIT, QCC48 |
| ACS8946 | ATM/SONET/SDH SUPPORT CIRCUIT, QCC48 |
| ACT-141223-2R | 1200 MHz - 1400 MHz RF/MICROWAVE NARROW BAND LOW POWER AMPLIFIER |
| ACT-141223-4R | 1200 MHz - 1400 MHz RF/MICROWAVE NARROW BAND LOW POWER AMPLIFIER |
| ACT-141223-4 | 1200 MHz - 1400 MHz RF/MICROWAVE NARROW BAND LOW POWER AMPLIFIER |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ACS8509T | 制造商:SEMTECH 制造商全称:Semtech Corporation 功能描述:Synchronous Equipment Timing Source for SONET or SDH Network Elements |
| ACS8510 | 制造商:Semtech Corporation 功能描述:Timing Source 100-Pin LQFP |
| ACS8510_03 | 制造商:SEMTECH 制造商全称:Semtech Corporation 功能描述:Synchronous Equipment Timing Source for SONET or SDH Network Elements |
| ACS8510REV2.1 | 制造商:Semtech Corporation 功能描述:Timing Source 100-Pin LQFP |
| ACS8510REV2.1SETS | 制造商:未知厂家 制造商全称:未知厂家 功能描述:Synchronous Equipment Timing Source for SONET or SDH Network Elements |
发布紧急采购，3分钟左右您将得到回复。