TNETE2004

MDIO-MANAGED QuadPHY

FOUR 10BASE-T PHYSICAL-LAYER INTERFACES

SPWS023D – OCTOBER 1996 – REVISED OCTOBER 1997

34

POST OFFICE BOX 655303

collision-detection timing

COL is asserted for a minimum of 600 ns when transmission and reception of data occur simultaneously. COL

is not active during link_fail or in full-duplex mode. Figure 26 through Figure 29 and the collision-detect timing

table show timing for modes of operation. Operation in all modes is identical except for polarity changes to TXEN

and COL. During a collision, the data output on RXD is not valid received data (or looped-back transmit data)

since the digital PLL is acquiring lock to a different source of incoming data.

collision-detect timing

MIN

TYP

MAX

UNIT

tCOLON

Collision-detect delay

50

ns

tCOLOFF

Collision-off time

325

ns

tCOLON

COL

(see Note A)

RCVP/

RCVN

NOTE A: COL high in mode 1 asserts collision.

tCOLOFF

TXEN

Figure 26. Mode 1 Collision

tCOLON

COL

(see Note A)

RCVP/

RCVN

NOTE A: COL low in mode 2 asserts collision.

tCOLOFF

TXEN

Figure 27. Mode 2 Collision