KSZ8873MLL Micrel Inc, KSZ8873MLL Datasheet - Page 18
![IC ETHERNET SWITCH 3PORT 64-LQFP](/photos/6/81/68149/64-lqfp-micrel_sml.jpg)
KSZ8873MLL
Manufacturer Part Number
KSZ8873MLL
Description
IC ETHERNET SWITCH 3PORT 64-LQFP
Manufacturer
Micrel Inc
Specifications of KSZ8873MLL
Data Rate
100Mbps
Controller Type
Ethernet Switch Controller
Interface
MII
Voltage - Supply
1.8V, 2.5V, 3.3V
Operating Temperature
0°C ~ 70°C
Mounting Type
Surface Mount
Package / Case
64-LQFP
No. Of Ports
3
Ethernet Type
IEEE 802.3u
Supply Current
115mA
Supply Voltage Range
2.5V, 3.3V
Digital Ic Case Style
LQFP
No. Of Pins
64
Svhc
No SVHC (15-Dec-2010)
Base
RoHS Compliant
Number Of Primary Switch Ports
3
Internal Memory Buffer Size
32
Fiber Support
No
Integrated Led Drivers
Yes
Phy/transceiver Interface
MII
Power Supply Type
Analog/Digital
Data Rate (typ)
10/100Mbps
Vlan Support
Yes
Operating Temperature (max)
70C
Operating Temperature (min)
0C
Mounting
Surface Mount
Jtag Support
No
Operating Supply Voltage (max)
1.89/3.465V
Operating Temperature Classification
Commercial
Interface Type
MII, RMII
Operating Temperature Range
0°C To +70°C
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Current - Supply
-
Lead Free Status / RoHS Status
Compliant, Lead free / RoHS Compliant
Other names
576-3459
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
KSZ8873MLL
Manufacturer:
Micrel Inc
Quantity:
1 934
Company:
Part Number:
KSZ8873MLL
Manufacturer:
ADI
Quantity:
27
Company:
Part Number:
KSZ8873MLL AM
Manufacturer:
Micrel
Quantity:
1 638
Company:
Part Number:
KSZ8873MLLJ
Manufacturer:
Micrel
Quantity:
323
Micrel, Inc.
100BASE-FX Signal Detection
In 100BASE-FX operation, FXSD (fiber signal detect), input pin 15 and 63, is usually connected to the fiber transceiver SD (signal
detect) output pin. The fiber signal threshold can be selected by register 192 bit 7 and 6 respectively for port 2 and port 1 , When
FXSD is less than the threshold, no fiber signal is detected and a far-end fault (FEF) is generated. When FXSD is over the
threshold, the fiber signal is detected.
Alternatively, the designer may choose not to implement the FEF feature. In this case, the FXSD input pin is tied high to force
100BASE-FX mode.
100BASE-FX signal detection is summarized in the following table:
To ensure proper operation, a resistive voltage divider is recommended to adjust the fiber transceiver SD output voltage swing to
match the FXSD pin’s input voltage threshold.
100BASE-FX Far-End Fault
A far-end fault (FEF) occurs when the signal detection is logically false on the receive side of the fiber transceiver. The KSZ8873FLL
detects a FEF when its FXSD input is Fiber Signal Threshold. When a FEF is detected, the KSZ8873FLL signals its fiber link partner
that a FEF has occurred by sending 84 1’s followed by a zero in the idle period between frames.
By default, FEF is enabled. FEF can be disabled through register setting.
10BASE-T Transmit
The 10BASE-T driver is incorporated with the 100BASE-TX driver to allow for transmission using the same magnetics. They are
internally wave-shaped and pre-emphasized into outputs with a typical 2.3V amplitude. The harmonic contents are at least 27dB
below the fundamental frequency when driven by an all-ones Manchester-encoded signal.
10BASE-T Receive
On the receive side, input buffers and level detecting squelch circuits are employed. A differential input receiver circuit and a phase-
locked loop (PLL) perform the decoding function. The Manchester-encoded data stream is separated into clock signal and NRZ data.
A squelch circuit rejects signals with levels less than 400mV or with short pulse widths to prevent noise at the RXP-or-RXM input from
falsely triggering the decoder. When the input exceeds the squelch limit, the PLL locks onto the incoming signal and the
KSZ8873MLL/FLL/RLL decodes a data frame. The receiver clock is maintained active during idle periods in between data reception.
MDI/MDI-X Auto Crossover
To eliminate the need for crossover cables between similar devices, the KSZ8873MLL/FLL/RLL supports HP Auto MDI/MDI-X and
IEEE 802.3u standard MDI/MDI-X auto crossover. HP Auto MDI/MDI-X is the default.
The auto-sense function detects remote transmit and receive pairs and correctly assigns transmit and receive pairs for the
KSZ8873MLL/FLL/RLL device. This feature is extremely useful when end users are unaware of cable types, and also, saves on an
additional uplink configuration connection. The auto-crossover feature can be disabled through the port control registers, or MIIM PHY
registers.
The IEEE 802.3u standard MDI and MDI-X definitions are:
September 2009
Register 192 bit 7 (port 2), bit 6 (port 1)
1
0
RJ-45 Pins
1
2
3
6
MDI
Table 2. MDI/MDI-X Pin Definitions
Table 1. FX Signal Threshold
Signals
RD+
TD+
RD-
TD-
18
RJ-45 Pins
2.0V
1.2V
Fiber Signal Threshold at FXSD
1
2
3
6
MDI-X
Signals
RD+
TD+
RD-
TD-
KSZ8873MLL/FLL/RLL
M9999-092309-1.2