Broadcom Corporation
Page iv Document 5221/5220-AN01-R
■ BCM5221 Application Note
■ BCM5220 7/7/00
TABLE OF CONTENTS
Revision History
Overview........................................................................................................................................................1
2.5V/3.3V Tolerance......................................................................................................................................1
Internal Pull-ups and Pull-downs................................................................................................................2
25 MHz Reference Clock ..............................................................................................................................3
RDAC .............................................................................................................................................................4
Low Power Modes ........................................................................................................................................4
Dual Function Pins.......................................................................................................................................4
PHYAD4/CK25.................................................................................................................................5
PHYAD3/PAUSE..............................................................................................................................5
PHYAD2/ACT_LED#........................................................................................................................5
PHYAD1/COL_LED#........................................................................................................................5
PHYAD0/FDX_LED#........................................................................................................................5
SPDLED#/ADV_PAUSE# ................................................................................................................5
100Base-FX ...................................................................................................................................................5
SD+/- ................................................................................................................................................7
RD+/-................................................................................................................................................7
TD+/- ................................................................................................................................................7
Serial 10m (7-Wire Interface) .......................................................................................................................7
Auto-MDI/MDIX Crossover...........................................................................................................................8
Magnetics......................................................................................................................................................9
Bel ....................................................................................................................................................9
Pulse Engineering ............................................................................................................................9
Halo..................................................................................................................................................9
Media Conversion.......................................................................................................................................10
Cable Length Monitoring Capability.........................................................................................................12
JTAG Considerations.................................................................................................................................12
JTAG Functional Description.................................................................................................................13
Eliminating Tri-State Buffer Requirement..............................................................................................13
Preferred Method ...........................................................................................................................13
Alternative Method .........................................................................................................................14
Supply Pins and Power Planes .................................................................................................................14
OVDD.............................................................................................................................................14