- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄364515 > 84221 84221 Quad 10/100 Mbps TX/FX/10BT (PHY) manual 1/99 PDF資料下載
參數(shù)資料
| 型號： | 84221 |
| 英文描述： | 84221 Quad 10/100 Mbps TX/FX/10BT (PHY) manual 1/99 |
| 中文描述： | 84221四10/100 Mbps的TX/FX/10BT（PHY）的手冊1 / 99 |
| 文件頁數(shù)： | 16/70頁 |
| 文件大小： | 1017K |
| 代理商： | 84221 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁當前第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁
16
MD400184/A
84221
The Manchester encoding process is only done on actual
packet data, and the idle period between packets is not
Manchester encoded, but filled with link pulses.
2.4 DECODER
2.4.1 4B5B Decoder - 100 Mbps
Since the TX input data is 4B5B encoded on the transmit
side, it must also be decoded by the 4B5B decoder on the
receive side. The mapping of the 5B nibbles to the 4B
code words is specified in IEEE 802.3 and shown in Table
2. The 84221 4B5B decoder takes the 5B code words
from the descrambler, converts them into 4B nibbles per
Table 2, and sends the 4B nibbles to the RMII controller
interface. The 4B5B decoder also strips off the SSD
delimiter (/J/K/ symbols) and replaces them with two 4B
Data 5 nibbles (/5/ symbol), and strips off the ESD
delimiter (/T/R/ symbols) and replaces it with two 4B Data
0 nibbles (/I/ symbol), per IEEE 802.3 specifications and
shown in Figure 2.
The 4B5B decoder detects SSD, ESD and, codeword
errors in the incoming data stream as specified in IEEE
802.3. These errors are indicated by asserting RXER
output while the errors are being transmitted across
RXD[1:0].
2.4.2 Manchester Decoder - 10 Mbps
In Manchester coded data, the first half of the data bit
contains the complement of the data, and the second half
of the data bit contains the true data. The 84221
Manchester decoder converts the single data stream from
the TP receiver into NRZ data for the controller interface
by decoding the data and stripping off the SOI pulse.
Since the clock and data recovery block has already
separated the clock and data from the TP receiver, the
Manchester decoding process to NRZ data is inherently
performed by that block.
2.5 CLOCK AND DATA RECOVERY
2.5.1 Clock Recovery - 100 Mbps
Clock recovery is done with a PLL. If there is no valid data
present on the receive inputs, the PLL is locked to the
CLKIN clock. When valid data is detected on the receive
inputs with the squelch circuit and when the adaptive
equalizer has settled, the PLL input is switched to the
incoming data stream. The PLL then recovers a clock by
locking onto the transitions of the incoming signal. The
recovered clock is output to the Controller Interface block.
2.5.2 Data Recovery - 100 Mbps
Data recovery is performed by latching in data from the
receive inputs with the recovered clock extracted by the
PLL.
2.5.3 Clock Recovery - 10 Mbps
The clock recovery process for 10 Mbps mode is identical
to the 100 Mbps mode, except:
The PLL is switched from CLKIN to the TP input when
the squelch indicates valid data.
The PLL locks onto the preamble signal in less than 12
transitions (bit times).
Some of the preamble data symbols are lost while the
PLL is locking onto the preamble, however, the data
receiver block recovers enough preamble symbols to
pass at least 3 bytes of preamble to the controller
interface as shown in Figure 3.
2.5.4 Data Recovery
The data recovery process for 10 Mbps mode is identical
to the 100 Mbps mode.
2.6 SCRAMBLER
2.6.1 100 Mbps
100BaseTX requires scrambling to reduce the radiated
emmisions on the twisted pair. The 84221 scrambler
takes the encoded data from the 4B5B encoder,
scrambles it per the IEEE 802.3 specifications, and sends
it to the TP transmitter. The scrambler circuitry of the
84221 is designed so that none of the individual scrambler
sections on-chip will be synchronous with the others to
minimize EMI issues.
2.6.2 10 Mbps
A scrambler is not used in 10 Mbps mode.
相關PDF資料 |
PDF描述 |
|---|---|
| 84221 | Quad 100BaseTX/100BaseFX/10BaseT Physical Layer Device （Highly Integrated Ethernet Transceiver For Twisted Pair And Fiber Ethernet Applications）(四通道100BaseTX/100BaseFX/10BaseT 物理層處理器（高度集成的以太網(wǎng)雙絞線和光纖數(shù)據(jù)收發(fā)器）) |
| 84301 | 84301 4-Port Fast Ethernet Controller manual 3/98 |
| 84301 | 4-Port Fast Ethernet Controller( 4端口快速以太網(wǎng)控制器) |
| 84717000 | MINIATURNAEHERUNGSSCHALTER 4MM GLATT PNP |
| 84717002 | MINIATURNAEHERUNGSSCHALTER M5 PNP |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| 842225 REV A1 | 制造商:Aavid Thermalloy 功能描述:- Bulk |
| 84222C | 功能描述:固定電感器 2.2uH 2.0A Mini SMT Power RoHS:否 制造商:AVX 電感:10 uH 容差:20 % 最大直流電流:1 A 最大直流電阻:0.075 Ohms 工作溫度范圍:- 40 C to + 85 C 自諧振頻率:38 MHz Q 最小值:40 尺寸:4.45 mm W x 6.6 mm L x 2.92 mm H 屏蔽:Shielded 端接類型:SMD/SMT 封裝 / 箱體:6.6 mm x 4.45 mm |
| 8422303301B | 制造商:ESSEX 功能描述:SPDT 277V. COIL ENCLOSED RELAY |
| 84223C | 功能描述:固定電感器 22uH 0.6A Mini SMT Power RoHS:否 制造商:AVX 電感:10 uH 容差:20 % 最大直流電流:1 A 最大直流電阻:0.075 Ohms 工作溫度范圍:- 40 C to + 85 C 自諧振頻率:38 MHz Q 最小值:40 尺寸:4.45 mm W x 6.6 mm L x 2.92 mm H 屏蔽:Shielded 端接類型:SMD/SMT 封裝 / 箱體:6.6 mm x 4.45 mm |
| 84224C | 功能描述:固定電感器 220uH 0.2A Mini SMT Power RoHS:否 制造商:AVX 電感:10 uH 容差:20 % 最大直流電流:1 A 最大直流電阻:0.075 Ohms 工作溫度范圍:- 40 C to + 85 C 自諧振頻率:38 MHz Q 最小值:40 尺寸:4.45 mm W x 6.6 mm L x 2.92 mm H 屏蔽:Shielded 端接類型:SMD/SMT 封裝 / 箱體:6.6 mm x 4.45 mm |
發(fā)布緊急采購，3分鐘左右您將得到回復。