SMSC LAN8710, FlexPWR RMII, FlexPWR MII, LAN8710i User Manual

LAN8710/LAN8710i
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR
Technology in a
Small Footprint
PRODUCT FEATURES
Highlights
Sin gle-Chip Ethernet Physical Layer Transceiver
(PHY)
Co mprehensive flexPWR
— Flexible Power Management Architecture — Power savings of up to 40% compared to competition — LVCMOS Variable I/O voltage range: +1.6V to +3.6V — Integrated 1.2V regulator with disable feature
HP Au to-MDIX supportSmall footprint 32 pin QFN le ad-free RoHS compliant
package (5 x 5 x 0.9mm height)
Target Applications
Set-Top BoxesNe tworked Printers and ServersTest InstrumentationL AN on MotherboardEmbed ded Telecom ApplicationsVideo Record/Playback SystemsCa ble Modems/RoutersDSL Modems/RoutersDi gital Video RecordersIP and Video PhonesW ireless Access PointsDi gital TelevisionsDi gital Media Adaptors/ServersGaming ConsolesPOE Appli cations
®
Technology
Datasheet
Key Benefits
H igh-Performance 10/100 Ethernet Transceiver
— Compliant with IEEE802.3/802.3u (Fast Ethernet) — Compliant with ISO 802-3/IEEE 802.3 (10BASE-T) — Loop-back modes — Auto-negotiation — Automatic polarity detection and correction — Link status change wake-up detection — Vendor specific register functions — Supports both MII and the reduced pin count RMII
interfaces
Po wer and I/Os
— Various low power modes — Integrated power-on reset circuit — Two status LED outputs — Latch-Up Performance Exceeds 150mA per EIA/JESD
78, Class II
— May be used with a single 3.3V supply
Packaging
— 32-pin QFN (5x5 mm) Lead-Free RoHS Compliant
package with MII and RMII
Environmental
— Extended Commercial Temperature Range (0°C to
+85°C)
— Industrial Temperature Range (-40°C to +85°C) version
available (LAN8710i)
SMSC LAN8710/LAN8710i Revision 1.0 (04-15-09)
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint
Datasheet
ORDER NUMBER(S):
LAN8710A-EZK FOR 32-PIN, QFN LEAD-FREE ROHS COMPLIANT PACKAGE (0 TO +85°C TEMP)
LAN8710Ai-EZK FOR 32-PIN, QFN LEAD-FREE ROHS COMPLIANT PACKAGE (-40 TO +85°C TEMP)
LAN8710A-EZK-TR FOR 32-PIN, QFN LEAD-FREE ROHS COMPLIANT PACKAGE (0 TO +85°C TEMP)
LAN8710Ai-EZK-TR FOR 32-PIN, QFN LEAD-FREE ROHS COMPLIANT PACKAGE (-40 TO +85°C TEMP)
Reel Size is 4000
80 ARKAY DRIVE, HAUPPAUGE, NY 11788 (631) 435-6000, FAX (631) 273-3123
Copyright © 2009 SMSC or its subsidiaries. All rights reserved. Circuit diagrams and other information relating to SMSC products are included as a mean s of illustrating typical applications. Conse quently, complete information sufficient for
construction purposes is not necessarily given. Although the information has been checked and is believed to be accurate, no responsibility is assumed for inaccuracies. SMSC reserves the right to make changes to specifications and product descriptions at any time without notice. Contact your local SMSC sales office to obtain the latest specifications before placing your product order. The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent rights or other intellectual property rights of SMSC or others. All sales are expressly conditional on your agreement to the terms and conditions of the most recently da ted version of SMSC's standard Terms of Sale Agreement dated before the date of your order (the "Terms of Sale Agreement"). The product may contain design defects or errors known as anomalies which may cause the product's functions to deviate from published specifications. Anomaly sheets are available upon request. SMSC products are not designed, intended, authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury or severe property damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or modification will be fully at the risk of the customer. Copies of this document or other SMSC literature, as well as the Terms of Sale Agreement, may be obtained by visiting SMSC’s website at http://www.smsc.com. SMSC is a registered trademark of Standard Microsystems Corporation (“SMSC”). Product names and company names are the trademarks of their respective holders.
SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND AGAINST INFRINGEMENT AND THE LIKE, AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE OF DEALING OR USAGE OF TRADE. IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT, INCIDENTAL, INDIRECT, SPECIAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES; OR FOR LOST DATA, PROFITS, SAVINGS OR REVENUES OF ANY KIND; REGARDLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRACT; TORT; NEGLIGENCE OF SMSC OR OTHERS; STRICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Revision 1.0 (04-15-09) 2 SMSC LAN8710/LAN8710i
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint
Datasheet
Table of Contents
Chapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.1 General Terms and Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.2 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.3 Architectural Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.3.1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Chapter 2 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.1 Package Pin-out Diagram and Signal Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Chapter 3 Pin Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1 MAC Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.2 LED Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.3 Management Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.4 General Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.5 10/100 Line Interface Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.6 Analog Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.7 Power Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Chapter 4 Architecture Details. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.1 Top Level Functional Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.2 100Base-TX Transmit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.2.1 100M Transmit Data Across the MII/RMII Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.2.2 4B/5B Encoding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.2.3 Scrambling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.2.4 NRZI and MLT3 Encoding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.2.5 100M Transmit Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.2.6 100M Phase Lock Loop (PLL). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.3 100Base-TX Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.3.1 100M Receive Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.3.2 Equalizer, Baseline Wander Correction and Clock and Data Recovery . . . . . . . . . . . . . 22
4.3.3 NRZI and MLT-3 Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3.4 Descrambling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3.5 Alignment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3.6 5B/4B Decoding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3.7 Receive Data Valid Signal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3.8 Receiver Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.3.9 100M Receive Data Across the MII/RMII Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.4 10Base-T Transmit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.4.1 10M Transmit Data Across the MII/RMII Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.4.2 Manchester Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.4.3 10M Transmit Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.5 10Base-T Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.5.1 10M Receive Input and Squelch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.5.2 Manchester Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.5.3 10M Receive Data Across the MII/RMII Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.5.4 Jabber Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.6 MAC Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.6.1 MII . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.6.2 RMII. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.6.3 MII vs. RMII Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.7 Auto-negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
SMSC LAN8710/LAN8710i 3 Revision 1.0 (04-15-09)
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint
Datasheet
4.7.1 Parallel Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.7.2 Re-starting Auto-negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.7.3 Disabling Auto-negotiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.7.4 Half vs. Full Duplex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.8 HP Auto-MDIX Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.9 Internal +1.2V Regulator Disable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.9.1 Disable the Internal +1.2V Regulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.9.2 Enable the Internal +1.2V Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.10 nINTSEL Strapping and LED Polarity Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.11 REGOFF and LED Polarity Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.12 PHY Address Strapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.13 Variable Voltage I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.14 Transceiver Management Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.14.1 Serial Management Interface (SMI). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Chapter 5 SMI Register Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
5.1 SMI Register Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
5.2 Interrupt Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.2.1 Primary Interrupt System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.2.2 Alternate Interrupt System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3 Miscellaneous Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3.1 Carrier Sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3.2 Collision Detect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.3.3 Isolate Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.3.4 Link Integrity Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.3.5 Power-Down modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.3.6 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
5.3.7 LED Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
5.3.8 Loopback Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
5.3.9 Configuration Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Chapter 6 AC Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
6.1 Serial Management Interface (SMI) Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
6.2 MII 10/100Base-TX/RX Timings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
6.2.1 MII 100Base-T TX/RX Timings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
6.2.2 MII 10Base-T TX/RX Timings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
6.3 RMII 10/100Base-TX/RX Timings (50MHz REF_CLK IN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
6.3.1 RMII 100Base-T TX/RX Timings (50MHz REF_CLK IN). . . . . . . . . . . . . . . . . . . . . . . . . 60
6.3.2 RMII 10Base-T TX/RX Timings (50MHz REF_CLK IN). . . . . . . . . . . . . . . . . . . . . . . . . . 62
6.4 RMII CLKIN Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
6.5 Reset Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
6.6 Clock Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Chapter 7 DC Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
7.1 DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
7.1.1 Maximum Guaranteed Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
7.1.2 Operating Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
7.1.3 Power Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
7.1.4 DC Characteristics - Input and Output Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Chapter 8 Application Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
8.1 Application Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
8.1.1 MII Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
8.1.2 Power Supply Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Revision 1.0 (04-15-09) 4 SMSC LAN8710/LAN8710i
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint
Datasheet
8.1.3 Twisted-Pair Interface Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
8.2 Magnetics Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Chapter 9 Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
SMSC LAN8710/LAN8710i 5 Revision 1.0 (04-15-09)
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint
Datasheet
List of Figures
Figure 1.1 LAN8710/LAN8710i System Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 1.2 LAN8710/LAN8710i Architectural Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 2.1 LAN8710/LAN8710i 32-QFN Pin Assignments (TOP VIEW). . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 4.1 100Base-TX Data Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 4.2 Receive Data Path. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 4.3 Relationship Between Received Data and Specific MII Signals . . . . . . . . . . . . . . . . . . . . . . 24
Figure 4.4 Direct Cable Connection vs. Cross-over Cable Connection . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 4.5 nINTSEL Strapping on LED2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Figure 4.6 REGOFF Configuration on LED1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 4.7 MDIO Timing and Frame Structure - READ Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 4.8 MDIO Timing and Frame Structure - WRITE Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 5.1 Near-end Loopback Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Figure 5.2 Far Loopback Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Figure 5.3 Connector Loopback Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Figure 6.1 SMI Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Figure 6.2 100M MII Receive Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 6
Figure 6.3 100M MII Transmit Timing Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Figure 6.4 10M MII Receive Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Figure 6.5 10M MII Transmit Timing Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Figure 6.6 100M RMII Receive Timing Diagram (50MHz REF_CLK IN). . . . . . . . . . . . . . . . . . . . . . . . . 60
Figure 6.7 100M RMII Transmit Timing Diagram (50MHz REF_CLK IN) . . . . . . . . . . . . . . . . . . . . . . . . 61
Figure 6.8 10M RMII Receive Timing Diagram (50MHz REF_CLK IN). . . . . . . . . . . . . . . . . . . . . . . . . . 62
Figure 6 .9 10M RMII Transmit Timing Diagr am (50MHz REF_CLK IN) . . . . . . . . . . . . . . . . . . . . . . . . . 63
Figure 6.10 Reset Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Figure 8.1 Simplified Application Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Figure 8.2 High-Level System Diagram for Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Figure 8.3 High-Level System Diagram for Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Figure 8.4 Copper Interface Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Figure 8.5 Copper Interface Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Figure 9.1 LAN8710/LAN8710i-EZK 32 Pin QFN Package Outline, 5 x 5 x 0.9 mm Body (Lead-Free). 76
Figure 9.1 QFN, 5x5 Taping Dimensions and Part Orientation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Figure 9.2 Reel Dimensions for 12mm Carrier Tape. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Figure 9.3 Tape Length and Part Quantity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Revision 1.0 (04-15-09) 6 SMSC LAN8710/LAN8710i
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Datasheet
List of Tables
Table 2. 1 LAN8710/LAN8710i 32-PIN QFN Pinout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Table 3.1 Buffer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 3.2 MII/RMII Signals 32-QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 3.3 LED Signals 32-QFN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Table 3.4 Management Signals 32-QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 3.5 General Signals 32-QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 3.6 10/100 Line Interface Signals 32-QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 3.7 Analog References 32-QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 3.8 Power Signals 32-QFN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 4.1 4B/5B Code Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 4.2 MII/RMII Signal Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table 4.3 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Table 5.1 Control Register: Register 0 (Basic) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Table 5.2 Status Register: Register 1 (Basic) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Table 5.3 PHY ID 1 Register: Register 2 (Extended) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Table 5.4 PHY ID 2 Register: Register 3 (Extended) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Table 5.5 Auto-Negotiation Advertisement: Register 4 (Extended). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 5.6 Auto-Negotiation Link Partner Base Page Ability Register: Register 5 (Extended). . . . . . . . . 36
Table 5.7 Auto-Negotiation Expansion Register: Register 6 (Extended). . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 5.8 Register 15 (Extended) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 5.9 Silicon Revision Register 16: Vendor-Specific. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 5.10 Mode Control/ Status Register 17: Vendor-Specific . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 5.11 Special Modes Register 18: Vendor-Specific . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 5.12 Register 24: Vendor-Specific. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 5.13 Register 25: Vendor-Specific. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 5.14 Symbol Error Counter Register 26: Vendor-Specific. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 5.15 Special Control/Status Indications Register 27: Vendor-Specific . . . . . . . . . . . . . . . . . . . . . . 38
Table 5.16 Special Internal Testability Control Register 28: Vendor-Specific . . . . . . . . . . . . . . . . . . . . . . 38
Table 5.17 Interrupt Source Flags Register 29: Vendor-Specific . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 5.18 Interrupt Mask Register 30: Vendor-Specific. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 5.19 PHY Special Control/Status Register 31: Vendor-Specific . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 5.20 SMI Register Mapping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Table 5.21 Register 0 - Basic Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Table 5.22 Register 1 - Basic Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Table 5.23 Register 2 - PHY Identifier 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 5.24 Register 3 - PHY Identifier 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 5.25 Register 4 - Auto Negotiation Advertisement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 5.26 Register 5 - Auto Negotiation Link Partner Ability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Table 5.27 Register 6 - Auto Negotiation Expansion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 5.28 Register 16 - Silicon Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 5.29 Register 17 - Mode Control/Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 5.30 Register 18 - Special Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 5.31 Register 26 - Symbol Error Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 5.33 Register 28 - Special Internal Testability Controls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 5.34 Register 29 - Interrupt Source Flags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 5.32 Register 27 - Special Control/Status Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 5.35 Register 30 - Interrupt Mask . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 5.36 Register 31 - PHY Special Control/Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 5.37 Interrupt Management Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 5.38 Alternative Interrupt System Management Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Table 5.39 Pin Names for Address Bits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Table 5.40 MODE[2:0] Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Table 5.41 Pin Names for Mode Bits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
. . . . 47
SMSC LAN8710/LAN8710i 7 Revision 1.0 (04-15-09)
DATASHEET
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Datasheet
Table 6.1 SMI Timing Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Table 6.2 100M MII Receive Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Table 6.3 100M MII Transmit Timing Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Table 6.4 10M MII Receive Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Table 6.5 10M MII Transmit Timing Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Table 6.6 100M RMII Receive Timing Values (50MHz REF_CLK IN). . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Table 6.7 100M RMII Transmit Timing Values (50MHz REF_CLK IN) . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Table 6.8 10M RMII Receive Timing Values (50MHz REF_CLK IN). . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Table 6.9 10M RMII Transmit Timing Values (50MHz REF_CLK IN) . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Table 6.10 RMII CLKIN (REF_CLK) Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Table 6.11 Reset Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Table 6.12 LAN8710/LAN8710i Crystal Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Table 7.1 Maximum Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Table 7.2 ESD and LATCH-UP Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Table 7.3 Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Table 7.4 Power Consumption Device Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Table 7.5 MII Bus Interface Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Table 7.6 LAN Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Table 7.7 LED Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Table 7.8 Configuration Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Table 7.9 General Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Table 7.10 Internal Pull-Up / Pull-Down Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Table 7.11 100Base-TX Transceiver Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Table 7.12 10BASE-T Transceiver Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Table 9.1 32 Terminal QFN Package Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Revision 1.0 (04-15-09) 8 SMSC LAN8710/LAN8710i
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Datasheet

Chapter 1 Introduction

1.1 General Terms and Conventions

The following is list of the general terms used in this docu ment:
BYTE 8-bits FIFO First In First Out buffer; often used for elasticity buffer MAC Media Access Controller MII Media Independent Interface RMIITM Reduced Media Independent InterfaceTM N/A Not Applicable X Indicates that a logic state is “don’t care” or undefined. RESERVED Refers to a reserved bit field or address. Unless otherwise noted, reserved
SMI Serial Management Interface
bits must always be zero for write operations. Unless otherwise noted, values are not guaranteed when reading reserved bits. Unless otherwise noted, do not read or write to reserved addresses.

1.2 General Description

The LAN8710/LAN8710i is a low-power 10BASE-T/100BASE-TX physical layer (PHY) transceiver that transmits and receives on unshielded twisted-pair cable. A typical system application is shown in
Figure 1.2. It is available in both extended commercial and industrial temperature operating versions.
The LAN8710/LAN8710i interfaces to the MAC layer using a variable voltage digital interface via the standard MII (IEEE 802.3u). Support for RMII makes a reduced pin-count interface available. The digital interface pins are tolerant to 3.6V.
The LAN8710/LAN8710i implements Auto-Negotiation to automatically determine the best possible speed and duplex mode of operation. HP Auto-MDIX su pport allows using a direct conne ct LAN cable, or a cross-over path cable.
The LAN8710 referenced throughout this document applies to both the extended commercial temperature and industrial temperature components. The LAN8710i refers to only the industrial temperature component.
SMSC LAN8710/LAN8710i 9 Revision 1.0 (04-15-09)
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Datasheet
10/100
Ethernet
MAC
MII o r RMII
MODE

Figure 1.1 LAN8710/LAN8710i System Block D iagram

LAN8710
Ethernet
Transceiver

1.3 Architectural Overview

The LAN8710/LAN8710i is compliant with IEEE 802.3-2 005 standards (MII Pins tolerant to 3.6V) and supports both IEEE 802.3-2005 compliant and vendor-specific register functions. It contains a full­duplex 10-BASE-T/100BASE-TX transceiver and supports 10-Mbps (10BASE-T) operation, and 100­Mbps (100BASE-TX) operation. The LAN8710/LAN8710i can be configured to operate on a single 3.3V supply utilizing an integrated 3.3V to 1.2V linear regulator. An option is available to disable the linear regulator to optimize system designs that have a 1.2V power supply available. This allows for the use of a high efficiency external regulator for lower system power dissipation.
Crystal or
Clock Osc
MDI
LED Status
Transformer RJ45

1.3.1 Configuration

The LAN8710 will begin normal operation following reset, an d no regi ster access is required . The initial configuration may be selected with configuration pins as described in Section 5.3.9. In addition, register-selectable configuration options may be used to further define the functionality of the transceiver. For example, the device can be set to 10BASE-T only. The LAN8710 supports both IEEE
802.3-2005 compliant and vendor-specific register functions.
Revision 1.0 (04-15-09) 10 SMSC LAN8710/LAN8710i
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint
Datasheet
MODE0 MODE1 MODE2
nRST
RMIISEL
TXD[0:3]
TXEN TXER
TXCLK
RXD[0:3]
RXDV RXER
RXCLK
CRS
COL/CRS_DV
MDC
MDIO
MODE Control
Reset
Control
SMI
RMII / MII Logic
Auto-
Negotiation
10M Tx
Logic
10M
Transmitter
Transmit Section
Management
Control
100M Tx
Logic
100M
Transmitter
MDIX
Control
100M Rx
Logic
DSP System:
Clock
Data Recovery
Analog-to-
Digital
Equalizer
Receive Section
10M Rx
Logic
100M PLL
Squelch &
Filters
10M PLL
Figure 1.2 LAN8710/LAN8710i Arch itectural Overview
HP Auto-MDIX
PLL
Interrupt
Generator
LED Circuitry
Central
Bias
PHY Address Latches
TXP / TXN
RXP / RXN
XTAL1/CLKIN XTAL2
nINT
LED1 LED2
RBIAS
PHYAD[0:2]
SMSC LAN8710/LAN8710i 11 Revision 1.0 (04-15-09)
DATASHEET
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology in a Small Footprint

Chapter 2 Pin Configuration

2.1 Package Pin-out Diagram and Signal Table

Datasheet
RXDV
26
15
COL/CRS_DV/MODE2
TXD3
2516
24 23 22 21 20 19 18 17
MDIO
TXD2 TXD1 TXD0 TXEN TXCLK nRST nINT/TXER/TXD4
MDC
VDD2A
LED2 /n INTSEL
LED1/REGOFF
XTAL2
XTAL1/CLKIN
VDDCR
RXCLK/PHYAD1
RXD3/PHYAD2
RBIAS
RXN
RXP
32
31
1 2 3 4 5 6 7 8
30
LAN8710/LAN8710i
32 PIN QFN
(Top Vie w )
9
10
11
RXD0/MDE0
RXD1/MODE1
RXD2/RMIISEL
TXP
29
SMSC
VSS
12
VDDIO
TXN
28
13
RXER/RXD4/PHYAD0
VDD1A
27
14
CRS

Figure 2.1 LAN8710/LAN8710i 32-QFN Pin Assign ments (TOP VIEW)

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Table 2.1 LAN8710/LAN8710i 32-PIN QFN Pinout

PIN NO. PIN NAME PIN NO. PIN NAME
1 VDD2A 17 MDC 2 LED2/nINTSEL 18 nINT/TXER/TXD4 3 LED1/REGOFF 19 nRST 4XTAL220 TXCLK 5 XTAL1/CLKIN 21 TXEN 6 VDDCR 22 TXD0 7 RXCLK//PHYAD1 23 TXD1 8 RXD3/PHYAD2 24 TXD2 9 RXD2/RMIISEL 25 TXD3
10 RXD1/MODE1 26 RXDV
1 1 RXD0/MODE0 27 VDD1A 12 VDDIO 28 TXN 13 RXER/RXD4/PHYAD0 29 TXP 14 CRS 30 RXN 15 COL/CRS_DV/MODE2 31 RXP 16 MDIO 32 RBIAS
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Chapter 3 Pin Description

This chapter describes the signals on each pin. When a lower case “n” is used at the beginning of the signal name, it indicates that the signal is active low. For example, nRST indicates that the reset signal is active low. The buffer type for each signal is indicated in the TYPE column, and a description of the buffer types is provided in Table 3.1.

Table 3.1 Buffer Types

BUFFER TYPE DESCRIPTION
I8 Input.
O8 Output with 8mA sink and 8mA source.
IOD8 Input/Open-drain output with 8mA sink.
Datasheet
IPU
Note 3.1
IPD
Note 3.1
IOPU
Note 3.1
IOPD
Note 3.1
AI Analog input
AIO Analog bi-directional
ICLK Crystal oscillator input pin
OCLK Crystal oscillator output pin
P Power pin
Note 3.1 Unless otherwise noted in the pin description, internal pull-u p and pull-down resistors are
Note: The dig ital signals are not 5V tolerant.They are variable vol tage from +1.6V to +3.6V, as shown
Input with 67k (typical) internal pull-up.
Input with 67k (typical) internal pull-down.
Input/Output with 67k (typical) internal pull-up. Output has 8 mA sink and 8mA source.
Input/Output with 67k (typical) internal pull-down. Output has 8mA sink and 8 mA source.
always enabled. The internal pull-up and pull -down resistors prevent unconnected inputs from floating, and must not be relied upon to drive signals external to When connected to a load that must be pulled hi gh or low, an external resistor must be added.
in Table 7.1.
LAN8710/LAN8710i.

3.1 MAC Interface Signals

T ab le 3.2 MII/RMII Signals 32-QFN

SIGNAL
NAME
TXD0 22 I8 Tr a ns m it D a ta 0: The MAC transmits data to the transceiver using this
TXD1 23 I8 Tr a ns m it D a ta 1: The MAC transmits data to the transceiver using this
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PIN # TYPE DESCRIPTION
signal in all modes.
signal in all modes
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Table 3.2 MII/RMII Signals (continued) 32-QFN (continued)
SIGNAL
NAME
32-QFN
PIN # TYPE DESCRIPTION
TXD2 24 I8 Tr a ns m it D a ta 2: The MAC transmits data to the transceiver using this
signal in MII Mode.
This signal should be g rounded in RMII Mode.
TXD3 25 I8 Tr a ns m it D a ta 3: The MAC transmits data to the transceiver using thi s
signal in MII Mode.
This signal should be g rounded in RMII Mode.
nINT/
TXER/
TXD4
18 IOPU nINT – Active low interrupt output. Place an external resistor pull-up to
VDDIO.
See Section 4.10 for information on how nINTSEL is used to determine
the function for this pin.
TXERMII Transmit Error: When driven high, the 4B/5B encode process substitutes the Transmit Error code-group (/H/) for the encoded data word. This input is ignored in 10Base-T operation.
TXD4MII Transmit Data 4: In Symbol Interface (5B Decoding) mode, this signal becomes the MII Transmit Data 4 line, the MSB of the 5-bit symbol code-group.
TXD4 is not used i n RMII Mode.This signal is mu x’d with nINT
TXEN 21 IPD Transmit Enable: Indicates that valid data is presented on the TXD[3:0]
signals, for transmission. In RMII Mode, only TXD[1:0] have vali d data.
TXCLK 20 O8 Tr a ns m it C l oc k : Used to latch data from the MAC into the transceiver.
MII (100BT): 25MHzMII (10BT): 2.5MHzThis signal is not used in R MII Mode.
RXD0/
MODE0
RXD1/
MODE1
RXD2/
RMIISEL
RXD3/
PHYAD2
11 IOPU RXD0Rece ive Data 0: Bit 0 of the 4 data bits that are sent by the
transceiver in the receive path. MODE0PHY Operating Mode Bit 0: set the default MODE of the PHY.
See Section 5.3.9.2 for information on the MODE options.
10 IOPU RXD1Receive Data 1: Bit 1 of the 4 data bits that are sent by the PHY
in the receive path. MODE1PHY Operating Mode Bit 1: set the default MODE of the PHY.
See Section 5.3.9.2 for information on the MODE options.
9IOPDRXD2 – Receive Data 2: Bit 2 of the 4 data bits that are sent by the
transceiver in the receive path.
The RXD2 signa l is not used in RMII Mode.
RMIISEL – MII/RMII Mode Selection: Latched on the rising edge of the internal reset (nRESET) based on the following strapping:
By default, MII mode is selected.Pull this pin high to VDDIO with an external resistor to select RMII mo de,
8IOPDRXD3 – Receive Data 3: Bit 3 of the 4 data bits that are sent by the
transceiver in the receive path.
This signal is not used in R MII Mode.This signal is mu x’d with PHYAD2
PHYAD2 – PHY Address Bit 2: set the SMI address of the transceiver.
See Section 5.3.9.1 for information on the ADDRESS options.
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Table 3.2 MII/RMII Signals (continued) 32-QFN (continued)
Datasheet
SIGNAL
NAME
RXER/ RXD4/
PHYAD0
32-QFN
PIN # TYPE DESCRIPTION
13 IOPD RXERReceive Error: Asserted to indicate that an error was detected
somewhere in the frame presently being transferred from the transceiver.
The RXER signal is optional in RMII Mode.
RXD4MII Receive Data 4: In Symbol Interface (5B Decoding) mode, this signal is the MII Receive Data 4 signal, the MSB of the received 5-bit symbol code-group. Unless configured in this mode, the pin functions as RXER.
This signal is mu x’d with PHYAD0
PHYAD0 – PHY Address Bit 0: set the SMI address of the PHY.
See Section 5.3.9.1 for information on the ADDRESS options.
RXCLK/
PHYAD1
7IOPDRXCLK – Receive Clock: In MII mode, this pin is the receive clock output.
25MHz in 100Base-TX mode. 2.5MHz in 10Base-T mode.
This signal is mu x’d with PHYAD1
PHYAD1 – PHY Address Bit 1: set the SMI address of the transceiver.
See Section 5.3.9.1 for information on the ADDRESS options.
RXDV 26 O8 Receive Data Valid: Indicates that recovered and decoded data is being
presented on RXD pins.
COL/
CRS_DV/
MODE2
15 IOPU COLMII Mode Collision Detect: Asserted to indicate detection of
collision condition. CRS_DVRMII Mode CRS_DV (Carrier Sense/Receive Data Valid)
Asserted to indicate when the receive medium is non-idle. When a 10BT packet is received, CRS_DV is asserted, but RXD[1:0] is held low until the SFD byte (10101011) is received. In 10BT, half-duplex mode, transmitted data is not looped back onto the receive data pins, per the RMII standard.
MODE2PHY Operating Mode Bit 2: set the default MODE of the PHY.
See Section 5.3.9.2 for information on the MODE options.
CRS 14 IOPD Carrier Sense: Indicates detection of carrier.

3.2 LED Signals

Table 3.3 LED Signals 32-QFN

SIGNAL
NAME
LED1/
REGOFF
32-QFN
PIN # TYPE DESCRIPTION
3IOPDLED1 – Link activity LED Indication.
See Section 5.3.7 for a description of LED modes. REGOFFRegulator Off: This pin may be used to configure the internal
1.2V regulator off. As described in Section 4.9, this pin is sampled during th e power-on sequence to determine if the internal regul ator should turn on. When the regulator is disabled, external 1.2V must be supplied to VDDCR.
When LED1/REGOFF is pulled high to VDD2A with an external resistor, the
internal regulator is disabled.
When LED1/REGOFF is floating or p ulled low, the internal regulator is
enabled (default).
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Table 3.3 LED Signals 32-QFN (continued)
SIGNAL
NAME
LED2/
nINTSEL
32-QFN
PIN # TYPE DESCRIPTION
2IOPULED2 – Link Speed LED Indication.
See Section 5.3.7 for a description of LED modes. nINTSEL: On power-up or external reset, the mode of the nINT/TXER/TXD4
pin is selected.
When LED2/nINTSEL i s floated or pulled to VDDIO, nINT is selected for
operation on pin nINT/TXER/TXD4 (default).
When LED2/nINTSEL is pulled low to VSS through a resistor, TXER/TXD4
is selected for operation on pin nINT/TXER/TXD4.
See Section 4.10 for additional information.

3.3 Management Signals

Table 3.4 Management Signals 32-QFN

SIGNAL
NAME
MDIO 16 IOD8 Management Data Input/OUTPUT: Serial management data input/output.
MDC 17 I8 Management Clock: Serial management cl ock.
32-QFN
PIN # TYPE DESCRIPTION

3.4 General Signals

T ab le 3.5 General Signals 32-QFN

SIGNAL
NAME
XTAL1/
CLKIN XTAL2 4 OCLK Clock Output: Crystal connection.
nRST 19 IOPU External Reset: Input of the system reset. This signal is active LOW.
32-QFN
PIN # TYPE DESCRIPTION
5ICLKClock Input: Crystal connection or external clock input.
Float this pin when an external clock is driven to XTAL1/CLKIN.

3.5 10/100 Line Interface Signals

Table 3.6 10/100 Line Interface Signals 32-QFN

SIGNAL
NAME
TXP 29 AIO Transmit/Receive Positive Channel 1.
32-QFN
PIN # TYPE DESCRIPTION
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Table 3.6 10/100 Line Interface Signals (continued) 32-QFN (continued)
Datasheet
SIGNAL
NAME
TXN 28 AIO Transmit/Receive Negative Channel 1. RXP 31 AIO Transmit/Receive Positive Channel 2. RXN 30 AIO Transmit/Receive Negative Channel 2.
32-QFN
PIN # TYPE DESCRIPTION

3.6 Analog Reference

Table 3.7 Analog References 32-QFN

SIGNAL
NAME
RBIAS 32 AI External 1% Bias Resistor. Requires a 12.1k ohm (1%) resistor to ground
32-QFN
PIN # TYPE DESCRIPTION
connected as described in the Analog Layout Guidelines. The nomin al voltage is 1.2V and the resistor will dissipate approximately 1mW of power.

3.7 Power Signals

Table 3.8 Power Signals 32-QFN

SIGNAL
NAME
VDDIO
VDDCR 6 P +1.2V (Core voltage) - 1.2V for digital circuitry on chip. Supplied by the on-
VDD1A 27 P +3.3V Analog Port Power to Channel 1. VDD2A 1 P +3.3V Analog Port Power to Channel 2 and to internal regulator.
VSS FLAG GND The flag must be connected to the ground plane with a via array under the
32-QFN
PIN # TYPE DESCRIPTION
12 P +1.6V to +3.6V Variable I/O Pad Power
chip regulator unless configured for regulator off mode us ing the LED1/REGOFF pin. A 1uF decoupling capacitor to ground should be used on this pin when using the internal 1.2V regulator.
exposed flag. This is the ground connection for the IC.
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Chapter 4 Architecture Details

4.1 Top Level Functional Architecture

Functionally, the transceiver can be divided into the following sections:
100Base-TX transmit and rece ive10Base-T transmit and receiveMII or RMII interface to the controllerAuto-negotiation to automatically determi ne the best speed and duplex possibleManagement Control to read status registers and write control reg isters
TX_CLK
(for MII only)
PLL
MAC
125 Mbps Serial
Ex t Re f_ CL K (fo r RMII on ly )
MII 25 Mhz by 4 bits
or
RMII 50Mhz by 2 bits
NRZI
Converter
M II/R MII
NRZI
Magnetics
25MHz
by 4 bits
MLT-3
Converter
MLT-3
4B/5B
Encoder
MLT-3

Figure 4.1 100Base-TX Data Path

4.2 100Base-TX Transmit

The data path of the 100Base-TX is shown in Figure 4.1. Each majo r block is explained below.

4.2.1 100M Transmit Data Across the MII/RMII Interface

25MHz by
5 bits
Tx
Driver
MLT-3MLT-3
Scrambler
and PISO
CAT-5RJ45
For MII, the MAC controller drives the transmit data onto the TXD bus and asserts TXEN to indicate valid data. The data is latched by the transceiver ’s MII block on the rising edge of TXCLK. The data is in the form of 4-bit wide 25MHz data.
For RMII, the MAC controller drives the transmit data onto the TXD bus and asserts TXEN to indicate valid data. The data is latched by the transceiver’s RMII block on the rising edge of REF _CLK. The data is in the form of 2-bit wide 50MHz data.
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4.2.2 4B/5B Encoding

The transmit data passes from the MII block to the 4B/5B encoder. This block encodes the data from 4-bit nibbles to 5-bit symbols (known as “code-groups”) according to Table 4.1. Each 4-bit data-nibble is mapped to 16 of the 32 possible code-groups. The remaining 16 code-groups are either used for control information or are not valid.
The first 16 code-groups are referred to by the hexadecimal values of their corre sponding data nibbles, 0 through F. The remaining code-groups are given letter designations with slashes on either side. For example, an IDLE code-group is /I/, a transmit error code-group is /H/, etc.
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The encoding process may be bypassed by clearing bit 6 of register 31. When the encoding is bypassed the 5
th
transmit data bit is equivalent to TXER.
Note that encoding can be bypassed only when the MAC interface is configured to operate in MII mode.
Table 4.1 4B/5B Code Table
CODE
GROUP SYM
RECEIVER
INTERPRETATION
TRANSMITTER
INTERPRETATION
11110 0 0 0000 DATA 0 0000 DATA 01001 1 1 0001 1 0001 10100 2 2 0010 2 0010 10101 3 3 0011 3 0011 01010 4 4 0100 4 0100 01011 5 5 0101 5 0101
01110 6 6 0110 6 0110
01111 7 7 0111 7 0111 10010 8 8 1000 8 1000 10011 9 9 1001 9 1001 10110 A A 1010 A 1010
10111 B B 1011 B 1011 11010 C C 1100 C 1100
11011 D D 1101 D 1101
11100 E E 1110 E 1110
11101 F F 1111 F 1111
11111 I IDLE Sent after /T/R until TXEN 11000 J First nibble of SSD, translated to “0101”
Sent for rising TXEN
following IDLE, else RXER
10001 K Second n ibble of SSD, translated to
Sent for rising TXEN
“0101” following J, else RXER
01101 T First nibble of ESD, causes de-assertion
Sent for falling TXEN of CRS if followed by /R/, else assertion of RXER
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Table 4.1 4B/5B Code Table (continued)
CODE
GROUP SYM
00111 R Second nibble of ESD, causes
deassertion of CRS if following /T/, else assertion of RXER
00100 H Transmit Error Symbol Sent for rising TXER 00110 V INVALID, RXER if during RXDV INVALID 11001 V INVALID, RXER if during RXDV INVALID 00000 V INVALID, RXER if during RXDV INVALID 00001 V INVALID, RXER if during RXDV INVALID 00010 V INVALID, RXER if during RXDV INVALID 00011 V INVALID, RXER if during RXDV INVALID 00101 V INVALID, RXER if during RXDV INVALID 01000 V INVALID, RXER if during RXDV INVALID 01100 V INVALID, RXER if during RXDV INVALID 10000 V INVALID, RXER if during RXDV INVALID
RECEIVER
INTERPRETATION
TRANSMITTER
INTERPRETATION
Sent for falling TXEN

4.2.3 Scrambling

Repeated data patterns (especially the IDLE code-group) can have power spectral densities with large narrow-band peaks. Scrambling the data helps eliminate these peaks and spread the signal power more uniformly over the entire channel bandwidth. This uniform spectral density is required by FCC regulations to prevent excessive EMI fr om being radiated by the physical wiring.
The seed for the scrambler is generated from the transceiver addre ss, PHYAD[4:0], ensuring that in multiple-transceiver applications, such as repeaters or switches, each transceiver will have its own scrambler sequence.
The scrambler also performs the Parallel In Serial Out conversion (PISO) of the data.

4.2.4 NRZI and MLT3 Encoding

The scrambler block passes the 5-bit wide parallel data to the NRZI converter where it becomes a serial 125MHz NRZI data stream. The NRZI is encoded to MLT-3. MLT3 is a tri-level code where a change in the logic level represents a code bit “1” an d the logic output remaining at the same level represents a code bit “0”.

4.2.5 100M Transmit Driver

The MLT3 data is then passed to the analog transmitter, which drives the differential MLT-3 signal, on outputs TXP and TXN, to the twisted pair media across a 1:1 ratio isolation transformer. The 10Base­T and 100Base-TX signals pass through the same transformer so that common “magnetics” can be used for both. The transmitter drives into the 100Ω impedance of the CAT-5 cable. Cable termination and impedance matching require external components.
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4.2.6 100M Phase Lock Loop (PLL)

The 100M PLL locks onto reference clo ck and generates the 125MHz clock used to drive the 125
MHz logic and the 100Base-Tx Transmitter.
TX_CLK
(for MII only)
Datasheet
PLL
MAC
125 Mbps Serial
Ex t Re f_ CL K (fo r RMII on ly )
MII 25 Mhz by 4 bits
or
RMII 50Mhz by 2 bits
NRZI
Converter
M II/R MII
Magnetics
Figure 4.2 Receive Data Path

4.3 100Base-TX Receive

The receive data path is shown in Figure 4.2. Detailed descriptions are given below.

4.3.1 100M Receive Input

NRZI
25MHz
by 4 bits
MLT-3
Converter
MLT-3
4B/5B
Encoder
MLT-3
25MHz by
5 bits
Tx
Driver
MLT-3MLT-3
Scrambler
and PISO
CAT-5RJ45
The MLT-3 from the cable is fed into the transceiver (on inputs RXP and RXN) via a 1:1 ratio transformer. The ADC samples the incoming differential signal at a rate of 125M samples per second. Using a 64-level quanitizer it generates 6 digital bits to represent each sample. The DSP adjusts the gain of the ADC according to the observed signal levels such that the full dynamic range of the ADC can be used.

4.3.2 Equalizer, Baseline Wander Correction and Clock and Data Recovery

The 6 bits from the ADC are fed into the DSP block. The equalizer in the DSP section compensates for phase and amplitude distortion caused by the physical channel consisting of magnetics, connectors, and CAT- 5 cable. The equalizer can restore the signal for any good-quality CAT-5 cable between 1m and 150m.
If the DC content of the signal is such that the low-frequency components fall below the low frequency pole of the isolation transformer, then the droop characteristics of the transformer will become significant and Baseline Wander (BLW) on the received signal will result. To prevent corruption of the received data, the transceiver corrects for BLW and can receive the ANSI X3.263-1995 FDDI TP-PMD defined “killer packet” with no bit errors.
The 100M PLL generates multiple phases of the 125MHz clock. A multiplexer, controlled by the timing unit of the DSP, selects the optimum phase for sampling the data. This is used as the received recovered clock. This clock is used to extract the serial data from the received signal.
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4.3.3 NRZI and MLT-3 Decoding

The DSP generates the MLT-3 recovered levels that are fed to the MLT-3 converter. The MLT-3 is then converted to an NRZI data stream.

4.3.4 Descrambling

The descrambler performs an inverse function to the scramb ler in the transmitter and also performs the Serial In Parallel Out (SIPO) conversion of the data.
During reception of IDLE (/I/) symbols. the descrambler synchronizes its descrambler key to the incoming stream. Once synchronization is achieved, the descrambler locks on this key and is able to descramble incoming data.
Special logic in the descrambler ensures synchronization with the remote transceiver by searching for IDLE symbols within a window of 4000 bytes (40us). This window ensures tha t a maximum packet size of 1514 bytes, allowed by the IEEE 802.3 standard, can be received with no interference. If no IDLE­symbols are detected within this time-period, receive operation is aborted and the descra m bler re-starts the synchronization process.
The descrambler can be bypassed by setting bit 0 of register 31.

4.3.5 Alignment

The de-scrambled signal is then aligned into 5-bit cod e-groups by recognizing the /J/K/ Start-of-Stream Delimiter (SSD) pair at the start of a packet. Once the code-word alignment is determined, it is stored and utilized until the next start of frame.

4.3.6 5B/4B Decoding

The 5-bit code-groups are translated into 4-bit data nibbles according to the 4B/5B table. The translated data is presented on the RXD[3:0] signal lines. The SSD, /J/K/, is translated to “0101 0101” as the first 2 nibbles of the MAC preamble. Recepti on of the SSD causes the transceiver to assert the RXDV signal, indicating that valid data is available on the RXD bus. Successive valid code-groups are translated to data nibbles. Reception of either the End of Stream Delimiter (ESD) consisting of the /T/R/ symbols, or at least two /I/ symbols causes the transceiver to de-assert carrier sense and RXDV.
These symbols are not translated into data. The decoding process may be bypassed by clearing bit 6 of register 31. When the decoding is
bypassed the 5 only when the MAC interface is in MII mode.
th
receive data bit is driven out on RXER/RXD4/PHYAD0. Decoding may be bypassed

4.3.7 Receive Data Valid Signal

The Receive Data Valid signal (RXDV) indicates that recovered and decoded nibbles are being presented on the RXD[3:0] outputs synchronous to RXCLK. RXDV becomes active after the /J/K/ delimiter has been recognized and RXD is aligned to nibble boundaries. It remains active until either the /T/R/ delimiter is recognized or link test indicates failure or SIGDET becomes false.
RXDV is asserted when the first nibble of translated /J/K/ is ready for transfer over the Media Independent Interface (MII mode).
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5D5
CLEAR-TEXT
5JK
data data data data
RX_CLK RX_DV
5D5 data data data data
RXD
5 55
Figure 4.3 Relationship Betwee n Received Data and Specific MII Signals

4.3.8 Receiver Errors

During a frame, unexpected code-groups are considered receive errors. Expected code groups are the DATA set (0 through F), and the /T/R/ (ESD) symbol pair. When a receive error occurs, the RXER signal is asserted and arbitrary data is driven onto the RXD[3:0] lines. Should an error be detected during the time that the /J/K/ delimiter is being decoded (bad SSD error), RXER is asserted true and the value ‘1110’ is driven onto the RXD[3:0] lines. Note that the Valid Data signal is not yet asserted when the bad SSD error occurs.

4.3.9 100M Receive Data Across the MII/RMII Interface

TR
Datasheet
Idle
In MII mode, the 4-bit data nibbles are sent to the MII block. These data nibbles are clocked to the controller at a rate of 25MHz. The controller samples the data on the rising edge of RXCLK. To ensure that the setup and hold requirements are met, the nibbles are clocked out of the transceiver on the falling edge of RXCLK. RXCLK is the 25MHz output clock for the MII bus. It is recovered from the received data to clock the RXD bus. If there is no received signal, it is derived from the system reference clock (XTAL1/CLKIN).
When tracking the received data, RXCLK has a maximum jitter of 0.8ns (provided that the jitter of the input clock, XTAL1/CLKIN, is below 100ps).
In RMII mode, the 2-bit data nibbles are sent to the RMII block. These data nibbles are clocked to the controller at a rate of 50MHz. The controller samples the data on the rising edge of XTAL1/CLKIN (REF_CLK). To ensure that the setup and hold requirements are met, the nibbles are clocked out of the transceiver on the falling edge of XTAL1/CLKIN (REF_CLK).

4.4 10Base-T Transmit

Data to be transmitted comes from the MAC layer controller. The 10Base-T transmitter receives 4-bit nibbles from the MII at a rate of 2.5MHz and converts them to a 10Mbps serial data stream. The data stream is then Manchester-encoded and sent to the analog transmitter, which drives a signal onto the twisted pair via the external magnetics.
The 10M transmitter uses the following blocks:
MII (digital)TX 10M (digital)10M Transmitter (analog)10M PLL (analog)

4.4.1 10M Transmit Data Across the MII/RMII Interface

The MAC controller drives the transmit data onto the TXD BUS. For MII, when the controller has driven TXEN high to indicate valid data, the data is latched by the MII block o n the rising edge of TXCLK. The data is in the form of 4-bit wide 2.5MHz data.
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