10/100 Non-PCI Ethernet Single Chip MAC + PHY

Datasheet

0

 

 

 

 

1.3

 

 

 

 

 

 

 

 

 

BT

BT

 

 

 

 

 

 

3.1 V

 

 

 

 

 

0.5 V/ns

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

585 mV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0.5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BT 0.6

2.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BT

4.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

300 mV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BT

+50 mV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+50 mV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-50 mV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0.25

 

 

 

 

 

200 mV

 

 

-50 mV

 

 

 

 

 

 

 

 

 

 

 

 

 

BT

 

 

 

4.0

42.0

BT

BT

 

-3.1 V

0.852.0

BTBT

Figure 7.7 Link Pulse Output Voltage Template - NLP, FLP100BASE-TX Link Integrity Algorithm -100Mbps

Since 100BASE-TX is defined to have an active idle signal, then there is no need to have separate link pulses like those defined for 10BASE-T. The LAN91C111 uses the squelch criteria and descrambler synchronization algorithm on the input data to determine if the device has successfully established a link with a remote device (called Link Pass State). Refer to IEEE 802.3 for both of these algorithms for more details.

AutoNegotiation Algorithm

As stated previously, the AutoNegotiation algorithm is used for two purposes: (1) To automatically configure the device for either 10/100 Mbps and Half/ Full Duplex modes, and (2) to establish an active link to and from a remote device. The AutoNegotiation algorithm is the same algorithm that is defined in IEEE 802.3 Clause 28. AutoNegotiation uses a burst of link pulses, called fast link pulses and referred to as FLP'S, to pass up to 16 bits of signaling data back and forth between the LAN91C111 and a remote device. The transmit FLP pulses meet the templated specified in IEEE 802.3 and shown in Figure 7.7. A timing diagram contrasting NLP's and FLP's is shown in Figure 7.8.

Revision 1.91 (08-18-08)

38

SMSC LAN91C111 REV C

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