KS8893MQL Micrel Inc, KS8893MQL Datasheet - Page 30

• Manufacturer Part Number: KS8893MQL
• Description: IC MANAGED SWITCH 10/100 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8893MQL

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• Number Of Primary Switch Ports: 3
• Internal Memory Buffer Size: 32
• Operating Supply Voltage (typ): 3.3V
• Fiber Support: Yes
• Integrated Led Drivers: Yes
• Power Supply Type: Analog/Digital
• Package Type: PQFP
• Data Rate (typ): 10/100Mbps
• Vlan Support: Yes
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Pin Count: 128
• Mounting: Surface Mount
• Jtag Support: No
• Operating Supply Voltage (max): 3.5V
• Operating Supply Voltage (min): 3.1V
• Operating Temperature Classification: Commercial
• Data Rate: 100Mbps
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-1457

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 KSZ8893MQL/MBL decodes a data
frame. The receiver clock is maintained active during idle periods in between data reception.
Power Management
The KSZ8893MQL/MBL features a per-port power down mode. To save power, a PHY port that is not in use can
be powered down via port control register, or MIIM PHY register.
In addition, there is a full chip power down mode. When activated, the entire chip is powered down.
MDI/MDI-X Auto Crossover
To eliminate the need for crossover cables between similar devices, the KSZ8893MQL/MBL 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 KSZ8893MQL/MBL 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:
December 2007
RJ-45 Pins
1
2
3
6
MDI
Table 2. MDI/MDI-X Pin Definitions
Signals
RD+
TD+
RD-
TD-
30
RJ-45 Pins
1
2
3
6
MDI-X
Signals
RD+
TD+
RD-
TD-
M9999-121007-1.5