KSZ8041NL Micrel Inc, KSZ8041NL Datasheet - Page 25

• Manufacturer Part Number: KSZ8041NL
• Manufacturer: Micrel Inc

Specifications of KSZ8041NL

• Lead Free Status / RoHS Status: Compliant

Micrel, Inc.
Receive Data Valid (RXDV)
RXDV is driven by the PHY to indicate that the PHY is presenting recovered and decoded nibbles on RXD[3:0].
RXDV transitions synchronously with respect to RXC.
Receive Data [3:0] (RXD[3:0])
RXD[3:0] transitions synchronously with respect to RXC. For each clock period in which RXDV is asserted, RXD[3:0]
transfers a nibble of recovered data from the PHY.
Receive Error (RXER)
RXER is asserted for one or more RXC periods to indicate that a Symbol Error (e.g. a coding error that a PHY is capable
of detecting, and that may otherwise be undetectable by the MAC sub-layer) was detected somewhere in the frame
presently being transferred from the PHY.
RXER transitions synchronously with respect to RXC. While RXDV is de-asserted, RXER has no effect on the MAC.
Carrier Sense (CRS)
CRS is asserted and de-asserted as follows:
Collision (COL)
COL is asserted in half-duplex mode whenever the transmitter and receiver are simultaneously active on the line. This is
used to inform the MAC that a collision has occurred during its transmission to the PHY.
COL transitions asynchronously with respect to TXC and RXC.
Reduced MII (RMII) Data Interface
The Reduced Media Independent Interface (RMII) specifies a low pin count Media Independent Interface (MII). It provides
a common interface between physical layer and MAC layer devices, and has the following key characteristics:
The KSZ8041NL is configured in RMII mode after it is power-up or reset with the following:
The KSZ8041RNL is configured in RMII mode and outputs the 50MHz RMII reference clock to the MAC on REF_CLK (pin
19) after it is power-up or reset with the following:
In RMII mode, unused MII signals, TXD[3:2] (pins 27, 26), are tied to ground.
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In 10Mbps mode, RXDV is asserted with the first nibble of the SFD (Start of Frame Delimiter), “5D”, and remains
asserted until the end of the frame.
In 100Mbps mode, RXDV is asserted from the first nibble of the preamble to the last nibble of the frame.
In 10Mbps mode, CRS assertion is based on the reception of valid preambles. CRS de-assertion is based on the
reception of an end-of-frame (EOF) marker.
In 100Mbps mode, CRS is asserted when a start-of-stream delimiter, or /J/K symbol pair is detected. CRS is de-
asserted when an end-of-stream delimiter, or /T/R symbol pair is detected. Additionally, the PMA layer de-asserts
CRS if IDLE symbols are received without /T/R.
Supports 10Mbps and 100Mbps data rates.
Uses a 50MHz reference clock.
Provides independent 2-bit wide (di-bit) transmit and receive data paths.
Contains two distinct groups of signals: one for transmission and the other for reception.
A 50MHz reference clock connected to REFCLK (pin 9).
CONFIG[2:0] (pins 18, 29, 28) set to ‘001’.
A 25MHz crystal connected to XI (pin 9) and XO (pin 8), or a 25MHz reference clock connected to XI (pin 9).
CONFIG[2:0] (pins 18, 29, 28) set to ‘001’.
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KSZ8041NL/RNL