TNETE2008

OctalPHY

EIGHT 10BASE-T PHYSICAL-LAYER INTERFACES

SPWS042B – DECEMBER 1997 – REVISED JUNE 1998

23

POST OFFICE BOX 655303

clock limits (see Figure 11)

NO.

PARAMETER

MIN

TYP

MAX

UNIT

1

tc(IFCLK)

Cycle time

50

ns

2

tw(IFCLK)

Pulse width high

22.5

27.5

ns

3

tw(IFCLK)

Pulse width low

22.5

27.5

ns

4

tr(IFCLK)

Rise time (see Note 7)

2

ns

5

tf(IFCLK)

Fall time (see Note 7)

2

ns

NOTE 7: Measured between 10% and 90% levels of IFCLK amplitude

IFCLK

(output)

1

4

5

2

3

Figure 11. Clock Limits

receive output interface (see Figure 12)

NO.

PARAMETER

MIN

MAX

UNIT

2

td(IFCOL)

Delay time, from IFCLK

↓ to IFCOL valid (see Note 8)

–2

10

ns

2

td(IFCRS)

Delay time, from IFCLK

↓ to IFCRS valid (see Note 9)

–2

10

ns

2

td(IFLINK)

Delay time, from IFCLK

↓ to IFLINK valid

–2

10

ns

2

td(IFRXD)

Delay time, from IFCLK

↓ to IFRXD valid (see Note 10)

–2

10

ns

2

td(IFRXDV)

Delay time, from IFCLK

↓ to IFRXDV invalid (see Note 11)

–2

10

ns

2

td(IFDUPLEX) Delay time, from IFCLK↓ to IFDUPLEX valid

–2

10

ns

NOTES:

8. For IFRX data, the TNETE2008 asserts IFCOL during the appropriate time slot if there was a collision event during previous time

slot.

9. For IFRX data, the TNETE2008 asserts IFCRS during the appropriate time slot if carrier was detected during previous time slot.

10. The TNETE2008 does not echo transmit data back on the IFRXD3–IFRXD0 terminals during normal operations.

11. The TNETE2008 asserts IFRXDV for IFRX data if there are four valid bits of data in the nibble. Dribble bits at the end of the frame

are discarded.

Valid

2

IFCLK

(output)

IFCOL

IFCRS

IFLINK

IFRXD3–IFRXD0

IFRXDV

IFDUPLEX

(outputs)

2

Figure 12. Multiplexed Receive Interface