The LTC6400-20 achieves this outstanding performance operating on a 3V supply voltage, providing a differential output voltage swing of 4.4VP-P. In addition to minimizing power consumption, this eliminates the need for a separate 5V supply in applications using the latest 3V and 3.3V ADCs. To further simplify interfacing to high speed ADCs such as the LTC2208, a VOCM pin sets the output common mode voltage of the LTC6400-20 to match the input range of the ADC. An optional on-chip filter helps to handle charge injection common to the capacitive inputs characteristic of pipelined ADCs. Inputs may be AC- or DC-coupled. While fully differential, the LTC6400-20 can be used to easily convert single-ended inputs to differential outputs.
The LTC6401-20 is a lower-power part optimized for lower input frequencies. Consuming just 50mA, half that of the LTC6400-20, the LTC6401-20 maintains the same low noise performance and -90dBc distortion performance for input frequencies up to 70MHz.
The LTC6400-20 is the first of a family of parts that achieves excellent noise and distortion performance from DC to hundreds of megahertz, says Kris Lokere, design manager. In addition to driving ADCs in communications and instrumentation applications, it will find many applications as a high performance differential driver and receiver.