Enhanced product LVDS SerDes transmitter

The SN65LVDS95 LVDS serdes (serializer/deserializer) transmitter contains three 7-bit parallel-load serial-out shift registers, a 7× clock synthesizer, and four low-voltage differential signaling (LVDS) line drivers in a single integrated circuit. These functions allow 21 bits of single-ended LVTTL data to be synchronously transmitted over 4 balanced-pair conductors for receipt by a compatible receiver, such as the SN65LVDS96.

When transmitting, data bits D0 through D20 are each loaded into registers of the SN65LVDS95 on the rising edge of the input clock signal (CLKIN). The frequency of CLKIN is multiplied seven times and then used to serially unload the data registers in 7-bit slices. The three serial streams and a phase-locked clock (CLKOUT) are then output to LVDS output drivers. The frequency of CLKOUT is the same as the input clock, CLKIN.

The SN65LVDS95 requires no external components and little or no control. The data bus appears the same at the input to the transmitter and output of the receiver with data transmission transparent to the user(s). The only user intervention is the possible use of the shutdown/clear (SHTDN) active-low input to inhibit the clock and shut off the LVDS output drivers for lower power consumption. A low level on this signal clears all internal registers to a low level.