TLK2541 Status: ACTIVE

Product Information

Features

• 1 to 2.6 Gigabits Per Second (Gbps)Serializer/Deserializer
• Independent Transmit/Receive Channels for Asynchronous Data Rate Operation
• Fast Relock at 1.25 Gbps and 2.5 Gbps for EPON OLT Applications
• Hot-Plug Protection
• High-Performance 80-Pin TQFP Package (PFP)
• 2.5-V Power Supply for Low Power Operation
• Programmable Preemphasis Levels on Serial Output
• Interfaces to Backplane, Copper Cables, or Optical Converters
• On-Chip 8-bit/10-bit Encoding/Decoding
• On-Chip PLL Provides Clock Synthesis From Low-Speed Reference
• Receiver Differential Input Thresholds 200 mV Minimum
• 3 V Tolerance on Parallel Data Input Signals
• Selectable 10 or 20 bit Parallel TTL Compatible Data Interface
• Industrial Temperature Range -40°C to 85°C
• Integrated 50-Ω Termination Resistors on RX
• Transmit FIFO Decouples Transmit Clock From Reference Clock
• APPLICATIONS
  • Next Generation EPON OLT Systems
  • Ideal for use with EPON OLT MAC Solutions such as TK3723 from Teknovus
  • Gigabit Ethernet and Fibre Channel Links

Description

The TLK2541 is a member of the WizardLink transceiver family of multigigabit transceivers, intended for usein high-speed bidirectional point-to-point data transmission systems. The TLK2541 supports an effective serial interface speed of 1 Gbps to 1.3 Gbps or 2 to 2.6 Gbps, providing over 2 Gbps of data bandwidth.

The primary application of this chip is to provide high-speed I/O data channels for point-to-point baseband data transmission over controlled impedance media of approximately 50Ω. The transmission media can be printed-circuit board, copper cables, or fiber-optic cable. The maximum rate and distance of data transfer is dependent upon the attenuation characteristics of the media and the noise coupling to the environment. The TLK2541 allows for independent transmit and receive data rate operation for applications that need asymmetrical data rates such as Passive Optical Networking.

This device can also be used to replace parallel data transmission architectures by providing a reduction in the number of traces, connector terminals, and transmit/receive terminals. Parallel data loaded into the transmitter is delivered to the receiver over a serial channel, which can be a coaxial copper cable, a controlled impedance backplane, or an optical link. It is then reconstructed into its original parallel format. It offers significant power and cost savings over parallel solutions, as well as scalability for higher data rates.

At full rate, the TLK2541 performs data conversion parallel-to-serial and serial-to-parallel. The clock extraction functions as a physical layer interface device. The serial transceiver interface operates at a maximum speed of 2.6 Gbps. The transmitter latches 20 parallel data at a rate based on the supplied transmit clock (TX_CLK).. The 20-bit word is then transmitted differentially at 20 times the reference clock (REFCLK) rate. The receiver section performs the serial-to-parallel conversion on the input data, synchronizing the resulting 20-bit wide parallel data to the recovered clock (RX_CLK). It then outputs the 20 bit recovered word on the receive data terminals RXD[0:19]. If the internal 8B/10B coding and decoding logic is enabled, 16 bits of data and two bits of control are latched on TX_CLK and the data is encoded into a 20 bit data word to be serialized. Likewise the 20 bit received data word is decoded into a 16 bit data word plus two bits of decode status.

At half rate, the TLK2541 only uses half of the parallel transmit and receive data busses. 10 bits of data on TXD[0:9] are latched by TX_CLK and serialized. If 8B/10B coding is enabled, 8 bits of data plus 1 bit of control is latched and the resulting 10 bit code word is serialized. The 10 bit received data word is output on RXD[0:9]. If 8B/10B decoding is enabled, the 10 bit received word is decoded and the 8 bit data plus 1 bit status is output.

The TLK2541 provides an internal loopback capability for self-test purposes. Serial data from the serializer is passed directly to the deserializer, providing the protocol device with a functional self-check of the physical interface.

The TLK2541 uses a 2.5-V supply. The I/O section is 3 V compatible. With the 2.5-V supply the chipset is very power efficient, consuming less than 625 mW typically. The TLK2541 is characterized for operation from -40°C to 85°C.

The TLK2541 is designed to be hot-plug capable. An on-chip power-on reset circuit holds the RX_CLK low and goes to high impedance on the parallel side output signal terminals as well as TXP and TXN during power up.