Texas Instruments TNETX4090 specifications PMA and Gmii clock see Figure, Gmii Clock

Models: TNETX4090

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TNETX4090

ThunderSWITCH II9-PORT 100-/1000-MBIT/S ETHERNETSWITCH

SPWS044E ± DECEMBER 1997 ± REVISED AUGUST 1999

PMA and GMII clock (see Figure 20)

NO.

 

 

MIN MAX

UNIT

 

 

 

 

 

1

tr(Mxx_GCLK)

Pulse width low, Mxx_RFCLK

2.5

ns

2

th(Mxx_GCLK)

Pulse width high, Mxx_RFCLK

2.5

ns

3

tw(Mxx_GCLK)

Cycle time, Mxx_RFCLK

8

ns

PMA and GMII clock (see Figure 20)

NO.

 

 

MIN

MAX

UNIT

 

 

 

 

 

 

1

tr(Mxx_GCLK)

Rise time, Mxx_RFCLK

 

1

ns

2

tf(Mxx_GCLK)

Fall time, Mxx_RFCLK

 

1

ns

3

Accuracy

 

100

 

PPM

 

 

 

 

 

 

 

duty cycle

 

40%

60%

 

 

 

 

 

 

 

²tr and tf are measured between 20% and 80%, VDD(3.3-V)= min, output load (GTCLK) = 20pf.

3

1 2

Mxx_RFCLK

Figure 20. GMII Clock

POST OFFICE BOX 655303 DALLAS, TEXAS 75265

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Page 65
Image 65
Texas Instruments TNETX4090 specifications PMA and Gmii clock see Figure, Gmii Clock