KS8993F Micrel Inc, KS8993F Datasheet - Page 44

• Manufacturer Part Number: KS8993F
• Description: IC CONV MED 10/100 3PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8993F

• 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): 1.8/2.5/3.3V
• Fiber Support: Yes
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII/SNI
• 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): 1.89/3.465V
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: KS8993F-EVAL - EVAL KIT EXPERIMENTAL KS8993F
• Lead Free Status / RoHS Status: Not Compliant, Lead free / RoHS Compliant

Similarly, SPI multiple write is initiated when the master device continues to drive the KS8993F SPIS_N input pin low
after a byte (a register) is written. The KS8993F internal address counter will increment automatically to the next byte
(next register) after the write. The next byte that is sent from the master device to the KS8993F SDA input pin will be
written to the next register address. SPI multiple write will continue until the SPI master device terminates it by de-
asserting the SPIS_N signal to the KS8993F.
For both SPI multiple read and multiple write, the KS8993F internal address counter will wrap back to register address
zero once the highest register address is reached. This feature allows all 128 KS8993F registers to be read, or written
with a single SPI command and any initial register address.
The KS8993F is capable of supporting a 5 MHz SPI bus.
The following is a sample procedure for programming the KS8993F using the SPI bus:
Micrel, Inc.
June 2009
1. At the board level, connect the KS8993F pins as follows:
2. Enable SPI slave mode by setting the KS8993F strap-in pins PS[1:0] (pins 100 and 101 respectively) to “10”.
3. Power up the board and assert reset to the KS8993F. After reset, the “Start Switch” bit (register 1 bit 0) will be
4. Configure the desired register settings in the KS8993F, using the SPI write or multiple write command.
5. Read back and verify the register settings in the KS8993F, using the SPI read or multiple read command.
6. Write a ‘1’ to the “Start Switch” bit to start the KS8993F with the programmed settings.
set to ‘0’.
Note: The “Start Switch” bit cannot be set to ‘0’ to stop the switch after an ‘1’ is written to this bit. Thus, it is
recommended that all switch configuration settings are programmed before the “Start Switch” bit is set to ‘1’.
Some of the configuration settings, such as “Aging enable”, “Auto Negotiation Enable”, “Force Speed” and
“Power down” can be programmed after the switch has been started.
KS8993F
Pin #
99
97
98
96
Table 9: KS8993F SPI Connections
Signal Name
KS8993F
SPIS_N
(SPIC)
(SPID)
SPIQ
SDA
SCL
44
(Master output; Slave input)
(Master input; Slave output)
External Processor
Signal Description
SPI Slave Select
SPI Clock
SPI Data
SPI Data
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or [phone]
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KS8993F/FL