RTL8308 REALTEK, RTL8308 Datasheet
RTL8308
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RTL8308 Summary of contents
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... The RTL8308 chip is a 128-pin low cost and ultra low power consumption 8-port 10/100M Ethernet switch controller integrated both with a 2M bits embedded DRAM as packet buffer and a 8K entries of address table. The RTL8308 supports reduced MII (RMII) interface. Only single 50MHz oscillator is needed in a switch system to save your Bill Of Material. In addition, the RTL8308 provides a LED display specially to indicate a network loop existence ...
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... Mbps data rate, and in full or half duplex mode. Speed, duplex, link status and flow control can be acquired by periodically polling the status of the PHY devices via MDIO. Address look-up table consists of 8K entries of hash table and a 128 entries of CAM. The RTL8308 uses address hashing algorithm or direct mapping method to search destination MAC address and record source MAC address from and to the hash table ...
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... Cut Through ............................................................................................................................................................................. 9 Broadcast Storm Control........................................................................................................................................................ 10 Loop Detection........................................................................................................................................................................ 10 Head-Of-Line Blocking........................................................................................................................................................... 10 24LC02 Interface .................................................................................................................................................................... 10 24LC02 Device Operation....................................................................................................................................................... 11 5. PIN ASSIGNMENT...................................................................................................................................................... 13 6. PIN DESCRIPTIONS ............................................................................................................................................... 14 7. SERIAL EEPROM 24LC02 FORMAT .................................................................................................................... 15 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory Page 3 ...
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... ELECTRICAL CHARACTERISTICS .................................................................................................................... 15 8 ................................................................................................................................... 15 EMPERATURE IMIT ATINGS 8 ................................................................................................................................................ 16 HARACTERISTICS 8 ................................................................................................................................................ 16 HARACTERISTICS 8.3.1 Reset and Clock Timing ................................................................................................................................................. 16 8.3.2 RMII Timing .................................................................................................................................................................. 17 8.3.3 PHY Management Timing ............................................................................................................................................. 18 8.3.4 Serial EEPROM 24LC02 Timing................................................................................................................................... 19 9. MECHANICAL INFORMATION............................................................................................................................ 20 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory Page 4 ...
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... After power on reset, the RTL8308 will determine some features from ENFCTRL, ENBKPRS and ENLOOP pins, auto-load the content of 24LC02 serial EEPROM, and write abilities to connected PHY management registers via MDC/MDIO most important that the RTL8308 and connected PHYs have to use the same reset signal source. Otherwise not guaranteed to work properly. ...
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... MAC address and record source MAC address from and to the table. If hashed or mapped location is not empty, the RTL8308 will compare the destination MAC address with the contents of the CAM for address searching and store source MAC address to CAM for learning ...
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... MAC address will be relocated into the 128-entry CAM accordingly. Using this eliminates the hash collision problem. Address Direct Mapping Mode In this mode, the RTL8308 uses the last 13 bits of MAC address to index to the 8K-entry look-up table. Illegal Frame The illegal frame such as CRC packet, runt packet(less than 64 bytes) and oversize packet(greater than 1724) will be discarded ...
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... Receive Data FIFO first and then is moved into Packet Buffer by Receive DMA Engine using the free page pointers in Receive Free Page Pointer FIFO via Get Free Page command. The RTL8308 always attempts to fill the Free Page Pointer FIFO up with free page pointers. 2000/1/5 Realtek Semiconductor Corp ...
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... The RTL8308 can operate in cut-through or store-and-forward mode. When in cut through mode (by pulled high the ENCUTHR pin), if receiving packet length is greater than 512 bytes, the RTL8308 starts to forward it after 512 bytes are received. If less than 512 bytes, the RTL8308 operates as same as store- and-forward mode. ...
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... The RTL8308 incorporate a simple mechanism to prevent Head-Of -Line blocking problem when flow control is disabled. When flow control function is disabled, the RTL8308 will first check the destination address of incoming packet. If the destined port is congested, then the RTL8308 will discard this packet to avoid the blocking of next packet which is going to loose traffic port. ...
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... Random Read: A random read requires a "dummy" byte write sequence to load in the data word address. Sequential Read: For RTL8308, the sequential reads are initiated by a random address read. After the 24LC02 receives a data word, it responds with an acknowledge. As long as the 24LC02 receives an acknowledge, it will continue to increment the data word address and serially clock out sequential data words ...
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... DUMMY WRITE *Sequential Read DEVICE ADDRESS SDA DATA n 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory DATA n+1 DATA n+x Page 12 ...
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... TXD1[A] 10 CRSDV[A] 11 RXD0[A] 12 RXD1[A] 13 TXE[B] 14 TXD0[B] 15 TXD1[B] 16 VCC 17 VCC 18 CRSDV[B] 19 RXD0[B] 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory RTL8308 83 GND 82 GND 81 RXD1[F] 80 RXD0[F] 79 CRSDV[F] 78 TXD1[F] 77 TXD0[F] 76 TXE[F] 75 GND 74 RXD1[E] 73 RXD0[E] 72 CRSDV[E] 71 GND 70 TXD1[E] 69 TXD0[E] ...
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... Reset: Active low to a known reset state. After power-on reset (low to high), the configuration modes from Mode Pins are determined, the content of serial EEPROM is auto- loaded into and the RTL8308 begins to access the management data of PHY devices. 119 System clock input 50 MHz system clock is used ...
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... When 0, address direct mapping algorithm used. 8. Electrical Characteristics 8.1 Temperature Limit Ratings: Parameter 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory 112 Enable Full Duplex Flow Control: Pulled high upon reset will enable the full duplex IEEE802.3x flow control function ...
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... SYSCLK clock frequency f clock (SYSCK) t1 SYSCLK clock period t2 RST# low pulse duration VDD SYSCLK RST# 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory -55 +125 0 70 Conditions Minimum Typical Maximum Unit I OH= -8mA 0.9 * Vcc I OL= 8mA ...
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... TXE ,TXD to REFCLK rising hold time t6 CSRDV ,RXD to REFCLK rising setup time t7 CRSDV ,RXD to REFCLK rising hold time REFCLK TXE TXD[1:0] REFCLK CRSDV RXD[1:0] 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory Minimum Typical - ...
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... MDC low level width t4 MDIO to MDC rising setup time (Write Bits) t5 MDIO to MDC rising hold time (Write Bits) t6 MDC to MDIO delay (Read Bits) t7 MDC/MDIO actives from RST# deasserted 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory Minimum - - - ...
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... Delay time, form SCLK falling to SDA changing t10 Delay time, from SDA valid input to SCLK rising SCLK t2 SDA (output) SDA (input) 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory Description VALID VALID t8 t9 ...
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... L1 0.053 0.063 0.073 1.35 y 0.004 0° 12° 0° 2000/1/5 Realtek Semiconductor Corp. Confidential RTL8308 8-port 10/100 Ethernet Switch Controller with Embedded Memory 1. Dimension D & not include interlead flash. Type Max 2. Dimension b does not include dambar rotrusion/intrusion. 3.40 3. Controlling dimension : Millimeter 0.25 0.91 4. General appearance spec. should be based on final visual 3 ...