DM9161 datasheet(21/50 Pages) DAVICOM

21 / 50 page

DM9161

10/100 Mbps Fast Ethernet Physical Layer TX/FX Single Chip Transceiver

Final

Version: DM9161-DS-F05

September 10, 2008

7.2.11 Power Reduced Mode

The Signal detect circuit is always turned on to monitor

whether there is any signal on the media. In case of cable

disconnection,, DM9161 will automatically turn off the power

and enter the Power Reduced mode, regardless of its

operation mode being N-way auto-negotiation or forced

mode. While in

the Power Reduced mode, the transmit

circuit will continue sending out fast link pules with minimum

power consumption. If a valid signal is detected from the

media, which might be N-way fast link pules, 10Base-T

normal link pules, or 100Base-TX MLT3 signals, the device

wakes up and resumes normal operation mode.

Automatic reduced power down mode can be disabled by

writing Zero to Reg.16.4.

7.2.12 Power Down Mode

Power Down mode is entered by setting Reg.0.11 to ONE or

pulling PWRDWN pin high, which disables all transmit and

receive functions, and MII interface functions except the

MDC/MDIO management interface.

7.2.13 Reduced Transmit Power Mode

Additional transmit power reduction can be gained by

designing with 1.25:1 turns ration magnetic on its TX side

and using a 8.5KΩ resistor on BGRES and BGRESG pins,

and the TX+/TX- pulled high resistors being changed from

50Ω to 78Ω. This configuration could reduce about 20% of

transmit power.

DM9161 Datasheet(PDF) 21 Page - Davicom Semiconductor, Inc.