82562GT Datasheet, PDF (23/46 Pages) Intel Corporation – 10/100 Mbps Platform LAN Connect (PLC)

Networking Silicon — 82562GT
• Differential pulses of peak magnitude less than 300 mV.
• Continuous sinusoids with a differential amplitude less than 6.2 V_PP and frequency less than 2
MHz.
• Sine waves of a single cycle duration starting with 0° or 180° phase that have a differential
amplitude less than 6.2 V_PP and a frequency of at least 2 MHz and not more than 16 MHz.
These single-cycle sine waves are discarded only if they are preceded by 4 bit times (400 ns)
of silence.
All other activity is determined to be either data, link test pulses, Auto-Negotiation fast link pulses,
or the idle condition.
5.3
Analog References
The 82562GT has two inputs, RBIAS100 and RBIAS10, that require external resistor connections
to set biases for its internal analog section. The input pins are sensitive to the resistor value and
experimentation is required to determine the correct values for any given layout. Note that the
values listed in Figure 4 are starting values. Also, resistors of 1% tolerance should be used.
Figure 4. Analog References
82562
651499Ω1%1%
619 1%
649 Ω 1%
RBIAS10
RBIAS100
5.4
Dynamic Reduced Power & Auto Plugging Detection
The 82562GT can be configured to support a dynamic reduced power mode. This mode reduces
power consumption of the 82562GT when LAN activity is not present. The reduced power mode
decreases power consumption from 300 mW to about 50 mW and is based on automatic detection
of cable plugging. If the 82562GT is configured to support dynamic power reduction, it enters the
reduced power mode whenever a cable is not connected to the device. In reduced power mode, the
82562GT shuts off the link circuits, except the circuit used for the automatic plugging detection.
On the LAN Connect side, the entire interface remains active, including full access to all Media
Independent Interface (MII) registers. In this mode, the 82562GT switches to the 10 Mbps speed
interface (5 MHz for LAN Connect). Thus, the reduced power mode is fully transparent to driver.
Datasheet
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