KSZ8721CL TR Micrel Inc, KSZ8721CL TR Datasheet - Page 15

• Manufacturer Part Number: KSZ8721CL TR
• Description: TXRX 10/100 3.3V 48-LQFP
• Manufacturer: Micrel Inc
• Type: Transceiverr

Specifications of KSZ8721CL TR

• Number Of Drivers/receivers: 1/1
• Protocol: MII
• Voltage - Supply: 3 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: KSZ8721CLTR; KSZ8721CLTR

April 2005
RMII Receive Timing
Auto-Crossover (Auto-MDI/MDI-X)
Automatic MDI/MDI-X configuration is intended to eliminate the need for crossover cables between similar devices. The
assignment of pinouts for a 10BASE-T/100BASE-TX crossover function cable is shown below.
This feature eliminates the confusion in applications by allowing the use of both straight and crossover cables. This feature
is controlled by register 1f:13. See the “Register 1fh–100BASE-TX PHY Controller” section for details.
KS8721CL
Parameter
REF_CLK Frequency
RXD[1:0], CRS_DV, RX_ER Output delay from REF_CLK rising edge
REF_CLK
RXD[1:0]
RXDV
RXER
Modular Connector (RJ-45)
Transmit Pair
Receive Pair
(Repeater or Switch)
Figure 1. Straight Through Cable
HUB
Figure 2. Crossover Cable
t
od
20ns
1
2
3
4
5
6
7
8
Crossover
Cable
15
Modular Connector (RJ-45)
(Repeater or Switch)
1
2
3
4
5
6
7
8
Transmit Pair
HUB
Receive Pair
Min
2.8
Typ
50
Max
10
M9999-041405
Micrel, Inc.
Units
MHz
ns