KSZ8041NL-EVAL Micrel Inc, KSZ8041NL-EVAL Datasheet - Page 28

• Manufacturer Part Number: KSZ8041NL-EVAL
• Description: BOARD EVALUATION FOR KSZ8041NL
• Manufacturer: Micrel Inc

Specifications of KSZ8041NL-EVAL

• Main Purpose: Interface, Ethernet PHY
• Embedded: No
• Utilized Ic / Part: KSZ8041NL
• Primary Attributes: Single Chip PHY, 10BASE-T/100BASE-TX
• Secondary Attributes: MII, RMII, HP Auto MDI, MDI-X Auto Polarity Correction
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-1621

Micrel, Inc.
The KSZ8041RNL RMII pin connections to the MAC are shown in Figure 3.
HP Auto MDI/MDI-X
HP Auto MDI/MDI-X configuration eliminates the confusion of whether to use a straight cable or a crossover cable
between the KSZ8041NL/RNL and its link partner. This feature allows the KSZ8041NL/RNL to use either type of cable to
connect with a link partner that is in either MDI or MDI-X mode. The auto-sense function detects transmit and receive
pairs from the link partner, and then assigns transmit and receive pairs of the KSZ8041NL/RNL accordingly.
HP Auto MDI/MDI-X is enabled by default. It is disabled by writing a one to register 1F bit 13. MDI and MDI-X mode is
selected by register 1F bit 14 if HP Auto MDI/MDI-X is disabled.
An isolation transformer with symmetrical transmit and receive data paths is recommended to support auto MDI/MDI-X.
The IEEE 802.3 Standard defines MDI and MDI-X as follows:
September 2010
RJ-45 Pin
1
2
3
6
Figure 3. KSZ8041RNL RMII Interface
MDI
Table 5. MDI/MDI-X Pin Definition
Signal
RD+
TD+
RD-
TD-
28
RJ-45 Pin
1
2
3
6
MDI-X
Signal
RD+
TD+
RD-
TD-
M9999-090910-1.4
KSZ8041NL/RNL