JITTER
鍙冩暩(sh霉)璩囨枡
鍨嬭櫉锛� XRT75L03IV-F
寤犲晢锛� Exar Corporation
鏂囦欢闋佹暩(sh霉)锛� 50/92闋�
鏂囦欢澶�?銆�?/td> 0K
鎻忚堪锛� IC LIU E3/DS3/STS-1 3CH 128LQFP
妯�(bi膩o)婧�(zh菙n)鍖呰锛� 72
椤炲瀷锛� 绶氳矾鎺ュ彛瑁濈疆锛圠IU锛�
椹�(q奴)鍕曞櫒/鎺ユ敹鍣ㄦ暩(sh霉)锛� 3/3
瑕�(gu墨)绋嬶細 DS3锛孍3锛孲TS-1
闆绘簮闆诲锛� 3.135 V ~ 3.465 V
瀹夎椤炲瀷锛� 琛ㄩ潰璨艰
灏佽/澶栨锛� 128-LQFP 瑁搁湶鐒婄洡
渚涙噳(y墨ng)鍟嗚ō(sh猫)鍌欏皝瑁濓細 128-LQFP锛�14x20锛�
鍖呰锛� 鎵樼洡
XRT75L03
REV. 1.0.4
THREE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER ATTENUATOR
51
6.2
JITTER TRANSFER - RECEIVER/TRANSMITTER:
Jitter Transfer function is defined as the ratio of jitter on the output relative to the jitter applied on the input
versus frequency.
There are two distinct characteristics in jitter transfer: jitter gain (jitter peaking) defined as the highest ratio
above 0dB; and jitter transfer bandwidth.The overall jitter transfer bandwidth is controlled by a low bandwidth
loop, typically using a voltage-controller crystal oscillator (VCXO).
The jitter transfer function is a ratio between the jitter output and jitter input for a component, or system often
expressed in dB. A negative dB jitter transfer indicates the element removed jitter. A positive dB jitter transfer
indicates the element added jitter.A zero dB jitter transfer indicates the element had no effect on jitter.
Table 12 shows the jitter transfer characteristics and/or jitter attenuation specifications for various data rates:
The above specifications can be met only with a jitter attenuator that supports E3/DS3/STS-1 rates.
6.3
Jitter Attenuator:
An advanced crystal-less jitter attenuator per channel is included in the XRT75L03. The jitter attenuator
requires no external crystal nor high-frequency reference clock.
In Host mode, by clearing or setting the JATx/Rx_n bits in the channel control registers selects the jitter
attenuator either in the Receive or Transmit path on per channel basis. In Hardware mode, JATx/Rx pin selects
globally all three channels either in Receive or Transmit path.
The FIFO size can be either 16-bit or 32-bit. In HOST mode, the bits JA0_n and JA1_n can be set to
appropriate combination to select the different FIFO sizes or to disable the Jitter Attenuator on a per channel
basis. In Hardware mode, appropriate setting of the pins JA0 and JA1 selects the different FIFO sizes or
disables the Jitter Attenuator for all three channels. Data is clocked into the FIFO with the associated clock
signal (TxClk or RxClk) and clocked out of the FIFO with the dejittered clock. When the FIFO is within two bits
of overflowing or underflowing, the FIFO limit status bit, FL_n is set to 鈥�1鈥� in the Alarm status register. Reading
this bit clears the FIFO and resets the bit into default state.
NOTE: It is recommended to select the 16-bit FIFO for delay-sensitive applications as well as for removing smaller amounts
of jitter. Table 13 specifies the jitter transfer mask requirements for various data rates:
TABLE 11: JITTER AMPLITUDE VERSUS MODULATION FREQUENCY (JITTER TOLERANCE)
BIT RATE
(KB/S)
STANDARD
INPUT JITTER AMPLITUDE (UI
P
-P)
MODULATION FREQUENCY
A1
A2
A3
F
1(HZ)
F
2(HZ)
F
3(KHZ)
F
4(KHZ)
F
5(KHZ)
34368
ITU-T G.823
1.5
0.15
-
100
1000
10
800
-
44736
GR-499
CORE Cat I
5
0.1
-
10
2.3k
60
300
-
44736
GR-499
CORE Cat II
10
0.3
-
10
669
22.3
300
-
51840
GR-253
CORE Cat II
15
1.5
0.15
10
30
300
2
20
TABLE 12: JITTER TRANSFER SPECIFICATION/REFERENCES
E3
DS3
STS-1
ETSI TBR-24
GR-499 CORE section 7.3.2
Category I and Category II
GR-253 CORE section 5.6.2.1
鐩搁棞(gu膩n)PDF璩囨枡
PDF鎻忚堪
XRT75L04DIV-F IC LIU E3/DS3/STS-1 4CH 176TQFP
XRT75L04IV-F IC LIU E3/DS3/STS-1 4CH 176LQFP
XRT75L06DIB-F IC LIU E3/DS3/STS-1 6CH 217BGA
XRT75L06IB-F IC LIU E3/DS3/STS-1 6CH 217BGA
XRT75R03DIV-F IC LIU E3/DS3/STS-1 3CH 128LQFP
鐩搁棞(gu膩n)浠g悊鍟�/鎶€琛�(sh霉)鍙冩暩(sh霉)
鍙冩暩(sh霉)鎻忚堪
XRT75L03IVTR 鍔熻兘鎻忚堪:鏅傞悩鍚堟垚鍣�/鎶栧嫊娓呴櫎鍣� 3CH E3/DS3/STS1 JITTER ATTENUATOR RoHS:鍚� 鍒堕€犲晢:Skyworks Solutions, Inc. 杓稿嚭绔暩(sh霉)閲�: 杓稿嚭闆诲钩: 鏈€澶ц几鍑洪牷鐜�: 杓稿叆闆诲钩: 鏈€澶ц几鍏ラ牷鐜�:6.1 GHz 闆绘簮闆诲-鏈€澶�:3.3 V 闆绘簮闆诲-鏈€灏�:2.7 V 灏佽 / 绠遍珨:TSSOP-28 灏佽:Reel
XRT75L03IVTR-F 鍔熻兘鎻忚堪:鏅傞悩鍚堟垚鍣�/鎶栧嫊娓呴櫎鍣� RoHS:鍚� 鍒堕€犲晢:Skyworks Solutions, Inc. 杓稿嚭绔暩(sh霉)閲�: 杓稿嚭闆诲钩: 鏈€澶ц几鍑洪牷鐜�: 杓稿叆闆诲钩: 鏈€澶ц几鍏ラ牷鐜�:6.1 GHz 闆绘簮闆诲-鏈€澶�:3.3 V 闆绘簮闆诲-鏈€灏�:2.7 V 灏佽 / 绠遍珨:TSSOP-28 灏佽:Reel
XRT75L04 鍒堕€犲晢:EXAR 鍒堕€犲晢鍏ㄧū:EXAR 鍔熻兘鎻忚堪:FOUR CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH JITTER
XRT75L04D 鍒堕€犲晢:EXAR 鍒堕€犲晢鍏ㄧū:EXAR 鍔熻兘鎻忚堪:FOUR CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
XRT75L04DES 鍔熻兘鎻忚堪:鏅傞悩鍚堟垚鍣�/鎶栧嫊娓呴櫎鍣� 4CH T3/E3/STS1 LIU+DESYNCH 3.3V RoHS:鍚� 鍒堕€犲晢:Skyworks Solutions, Inc. 杓稿嚭绔暩(sh霉)閲�: 杓稿嚭闆诲钩: 鏈€澶ц几鍑洪牷鐜�: 杓稿叆闆诲钩: 鏈€澶ц几鍏ラ牷鐜�:6.1 GHz 闆绘簮闆诲-鏈€澶�:3.3 V 闆绘簮闆诲-鏈€灏�:2.7 V 灏佽 / 绠遍珨:TSSOP-28 灏佽:Reel