Texas Instruments

The DS90CR215 transmitter converts 21 bits of CMOS/TTL data into three LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fourth LVDS link. Every cycle of the transmit clock 21 bits of input data are sampled and transmitted. The DS90CR216 receiver converts the LVDS data streams back into 21 bits of CMOS/TTL data. At a transmit clock frequency of 66 MHz, 21 bits of TTL data are transmitted at a rate of 462 Mbps per LVDS data channel. Using a 66 MHz clock, the data throughput is 1.386 Gbit/s (173 Mbytes/s). The multiplexing of the data lines provides a substantial cable reduction. Long distance parallel single-ended buses typically require a ground wire per active signal (and have very limited noise rejection capability). Thus, for a 21-bit wide data and one clock, up to 44 conductors are required. With the Channel Link chipset as few as 9 conductors (3 data pairs, 1 clock pair and a minimum of one ground) are needed. This provides a 80% reduction in required cable width, which provides a system cost savings, reduces connector physical size and cost, and reduces shielding requirements due to the cables' smaller form factor. The 21 CMOS/TTL inputs can support a variety of signal combinations. For example, five 4-bit nibbles plus 1 control, or two 9-bit (byte + parity) and 3 control. The DS90CR215 transmitter converts 21 bits of CMOS/TTL data into three LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fourth LVDS link. Every cycle of the transmit clock 21 bits of input data are sampled and transmitted. The DS90CR216 receiver converts the LVDS data streams back into 21 bits of CMOS/TTL data. At a transmit clock frequency of 66 MHz, 21 bits of TTL data are transmitted at a rate of 462 Mbps per LVDS data channel. Using a 66 MHz clock, the data throughput is 1.386 Gbit/s (173 Mbytes/s). The multiplexing of the data lines provides a substantial cable reduction. Long distance parallel single-ended buses typically require a ground wire per active signal (and have very limited noise rejection capability). Thus, for a 21-bit wide data and one clock, up to 44 conductors are required. With the Channel Link chipset as few as 9 conductors (3 data pairs, 1 clock pair and a minimum of one ground) are needed. This provides a 80% reduction in required cable width, which provides a system cost savings, reduces connector physical size and cost, and reduces shielding requirements due to the cables' smaller form factor. The 21 CMOS/TTL inputs can support a variety of signal combinations. For example, five 4-bit nibbles plus 1 control, or two 9-bit (byte + parity) and 3 control.

The DS90CR217 transmitter converts 21 bits of CMOS/TTL data into three LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fourth LVDS link. Every cycle of the transmit clock 21 bits of input data are sampled and transmitted. At a transmit clock frequency of 85 MHz, 21 bits of TTL data are transmitted at a rate of 595 Mbps per LVDS data channel. Using a 85 MHz clock, the data throughput is 1.785 Gbit/s (223 Mbytes/sec). The narrow bus and LVDS signalling of the DS90CR217 is an ideal means to solve EMI and cable size problems associated with wide, high-speed TTL interfaces. The DS90CR217 transmitter converts 21 bits of CMOS/TTL data into three LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fourth LVDS link. Every cycle of the transmit clock 21 bits of input data are sampled and transmitted. At a transmit clock frequency of 85 MHz, 21 bits of TTL data are transmitted at a rate of 595 Mbps per LVDS data channel. Using a 85 MHz clock, the data throughput is 1.785 Gbit/s (223 Mbytes/sec). The narrow bus and LVDS signalling of the DS90CR217 is an ideal means to solve EMI and cable size problems associated with wide, high-speed TTL interfaces.

The DS90CR218A receiver deserializes three input LVDS data streams into 21 bits of CMOS/TTL output data. When operating at the maximum input clock rate of 85 Mhz, the LVDS data is received at 595 Mbps per data channel for a total data throughput of 1.785 Gbit/sec (233 Mbytes/sec). The narrow bus and LVDS signalling of the DS90CR218A is an ideal means to solve EMI and cable size problems associated with wide, high-speed TTL interfaces. The DS90CR218A receiver deserializes three input LVDS data streams into 21 bits of CMOS/TTL output data. When operating at the maximum input clock rate of 85 Mhz, the LVDS data is received at 595 Mbps per data channel for a total data throughput of 1.785 Gbit/sec (233 Mbytes/sec). The narrow bus and LVDS signalling of the DS90CR218A is an ideal means to solve EMI and cable size problems associated with wide, high-speed TTL interfaces.

The DS90CR286AT-Q1 receiver converts four LVDS (Low Voltage Differential Signaling) data streams back into parallel 28 bits of LVCMOS data. The receiver data outputs strobe on the output clock's rising edge. The receiver LVDS clock operates at rates from 20 to 66 MHz. The DS90CR286AT-Q1 phase-locks to the input LVDS clock, samples the serial bit streams at the LVDS data lines, and converts them into 28-bit parallel output data. At an incoming clock rate of 66 MHz, each LVDS input line is running at a bit rate of 462 Mbps, resulting in a maximum throughput of 1.848 Gbps. The DS90CR286AT-Q1 device is enhanced over prior generation receivers due to a wider data valid time on the receiver output. The DS90CR286AT-Q1 is designed for PCB board chip-to-chip OpenLDI-to-RGB bridge conversion. LVDS data transmission over cable interconnect is not recommended for this device. Users designing a sub-system with a compatible OpenLDI transmitter and DS90CR286AT-Q1 receiver must ensure an acceptable skew margin budget (RSKM). Details regarding RSKM can be found in the Application Information section. The DS90CR286AT-Q1 receiver converts four LVDS (Low Voltage Differential Signaling) data streams back into parallel 28 bits of LVCMOS data. The receiver data outputs strobe on the output clock's rising edge. The receiver LVDS clock operates at rates from 20 to 66 MHz. The DS90CR286AT-Q1 phase-locks to the input LVDS clock, samples the serial bit streams at the LVDS data lines, and converts them into 28-bit parallel output data. At an incoming clock rate of 66 MHz, each LVDS input line is running at a bit rate of 462 Mbps, resulting in a maximum throughput of 1.848 Gbps. The DS90CR286AT-Q1 device is enhanced over prior generation receivers due to a wider data valid time on the receiver output. The DS90CR286AT-Q1 is designed for PCB board chip-to-chip OpenLDI-to-RGB bridge conversion. LVDS data transmission over cable interconnect is not recommended for this device. Users designing a sub-system with a compatible OpenLDI transmitter and DS90CR286AT-Q1 receiver must ensure an acceptable skew margin budget (RSKM). Details regarding RSKM can be found in the Application Information section.

The DS90CR287 transmitter converts 28 bits of LVCMOS/LVTTL data into four LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fifth LVDS link. Every cycle of the transmit clock 28 bits of input data are sampled and transmitted. The DS90CR288A receiver converts the four LVDS data streams back into 28 bits of LVCMOS/LVTTL data. At a transmit clock frequency of 85 MHz, 28 bits of TTL data are transmitted at a rate of 595 Mbps per LVDS data channel. Using a 85 MHz clock, the data throughput is 2.38 Gbit/s (297.5 Mbytes/sec). This chipset is an ideal means to solve EMI and cable size problems associated with wide, high-speed TTL interfaces. The DS90CR287 transmitter converts 28 bits of LVCMOS/LVTTL data into four LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fifth LVDS link. Every cycle of the transmit clock 28 bits of input data are sampled and transmitted. The DS90CR288A receiver converts the four LVDS data streams back into 28 bits of LVCMOS/LVTTL data. At a transmit clock frequency of 85 MHz, 28 bits of TTL data are transmitted at a rate of 595 Mbps per LVDS data channel. Using a 85 MHz clock, the data throughput is 2.38 Gbit/s (297.5 Mbytes/sec). This chipset is an ideal means to solve EMI and cable size problems associated with wide, high-speed TTL interfaces.