ICS1894-40
10BASE-T/100BASE-TX INTEGRATED PHYCEIVER WITH RMII INTERFACE PHYCEIVER
IDT®
10BASE-T/100BASE-TX INTEGRATED PHYCEIVER WITH RMII INTERFACE 47
ICS1894-40 REV K 022412
10Base-T: Heartbeat Timing (SQE)
The table below lists the significant time periods for the 10Base-T heartbeat (that is, the Signal Quality Error). The
time periods consist of timings of signals on the following pins:
• TXEN
• TXCLK
• COL
The 10Base-T Heartbeat (SQE) Timing Diagram shows the timing diagram for the time periods.
Note:
1. For more information on 10Base-T SQE operations, see the section “10Base-T Operation: SQE Test”.
2. In 10Base-T mode, one bit time = 100 ns.
10Base-T Heartbeat (SQE) Timing Diagram
Time
Period
Parameter Conditions Min. Typ. Max. Units
t1 COL Heartbeat Assertion Delay from
TXEN De-Assertion
10Base-T Half Duplex – 850 1500 ns
t2 COL Heartbeat Assertion Duration 10Base-T Half Duplex – 1000 1500 ns
