Texas Instruments TNETX3270 Timing requirements see Figure, 10-/100-Mbit/stransmit ports 24, 25

Models: TNETX3270

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TNETX3270

ThunderSWITCH24/3 ETHERNETSWITCH

WITH 24 10-MBIT/S PORTS AND 3 10-/100-MBIT/S PORTS

SPWS043B ± NOVEMBER 1997 ± REVISED APRIL 1999

10-/100-Mbit/stransmit ports (24, 25, and 26)

timing requirements (see Figure 15)

NO.

 

 

MIN

MAX

UNIT

 

 

 

 

 

 

1

tc(MxxTCLK)

Cycle time, MxxTCLK

25

25

ns

2

tw(MxxTCLKL)

Pulse duration, MxxTCLK low

 

 

ns

3

tw(MxxTCLKH)

Pulse duration, MxxTCLK high

14

 

ns

operating characteristics over recommended operating conditions (see Note 8 and Figure 15)

NO.

 

 

 

 

 

PARAMETER

 

 

 

 

 

 

 

MIN

MAX

UNIT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4²

 

t

d(MxxTXD)

Delay time, from MxxTCLKto MxxTXD3±MxxTXD0 valid

0

25

ns

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4²

 

t

d(MxxTXEN)

Delay time, from MxxTCLKto MxxTXEN valid

 

 

 

 

 

 

 

0

25

ns

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4²

 

t

d(MxxTXER)

Delay time, from MxxTCLKto MxxTXER valid

 

 

 

 

 

 

 

0

25

ns

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

² xx = ports 24, 25, and 26

 

 

 

 

 

 

 

 

 

 

NOTE 8:

Both MxxCRS and MxxCOL are driven asynchronously by the PHY. MxxTXD3±MxxTXD0 is driven by the reconciliation sublayer

 

 

 

synchronous to the MxxTCLK. MxxTXEN is asserted and deasserted by the reconciliation sublayer synchronous to the MxxTCLK rising

 

 

 

edge. MxxTXER is driven synchronous to the rising edge of MxxTCLK.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2

 

 

 

 

 

 

3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MxxTCLK (input)

MxxTXD3±MxxTXD0

MxxTXEN

MxxTXER

(outputs)

Figure 15. 10-/100-Mbit/s Transmit Ports

POST OFFICE BOX 655303 DALLAS, TEXAS 75265

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Texas Instruments TNETX3270 specifications Timing requirements see Figure, 10-/100-Mbit/stransmit ports 24, 25