KS8842-32MQL Micrel Inc, KS8842-32MQL Datasheet - Page 29

• Manufacturer Part Number: KS8842-32MQL
• Description: IC SWITCH 10/100 32BIT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8842-32MQL

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• Number Of Primary Switch Ports: 2
• Internal Memory Buffer Size: 32
• Operating Supply Voltage (typ): 3.3V
• Fiber Support: Yes
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII
• 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
• For Use With: KS8842-PMQL-EVAL - EVAL KIT EXPERIMENTAL KS8842KS8842-16MQL-EVAL - EVAL KIT EXPERIMENTAL KS8842
• Lead Free Status / RoHS Status: Not Compliant, Lead free / RoHS Compliant
• Other names: 576-1459

Power Management
The KSZ8842M features per port power-down mode. To save power, the user can power-down the port that is not in use
by setting bit 11 in either P1CR4 or P1MBCR register for port 1 and setting bit 11 in either P2CR4 or P2MBCR register for
port 2. To bring the port back up, reset bit 11 in these registers.
In addition, there is a full switch power-down mode. This mode shuts the entire switch down, when the PWRDN (pin 36) is
pulled down to low.
MDI/MDI-X Auto Crossover
To eliminate the need for crossover cables between similar devices, the KSZ8842M 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 the transmit and receive pairs for
the KSZ8842M device. This feature is extremely useful when end users are unaware of cable types in addition to saving
on an additional uplink configuration connection. The auto-crossover feature can be disabled through the port control
registers.
The IEEE 802.3u standard MDI and MDI-X definitions are:
Straight Cable
A straight cable connects an MDI device to an MDI-X device or an MDI-X device to an MDI device. The following diagram
shows a typical straight cable connection between a network interface card (NIC) (MDI) and a switch, or hub (MDI-X).
Micrel, Inc.
October 2007
RJ45 Pins
Figure 7. Typical Straight Cable Connection
1
2
3
6
Table 1. MDI/MDI-X Pin Definitions
MDI
Signals
TD+
RD+
RD-
TD-
29
RJ45 Pins
1
2
3
6
MDI-X
Signals
RD+
TD+
RD-
TD-
KSZ8842-16/32 MQL/MVL/MVLI/MBL
M9999-102207-1.9