Features

• Low Phase Noise Buffer/Driver
• Optimized Conversion of Sine Wave Signals to Logic Levels
• Three Logic Output Types Available
  – LVPECL
  – LVDS
  – CMOS
• Additive Jitter 45fs_RMS (LTC6957-1)
• Frequency Range Up to 300MHz
• 3.15V to 3.45V Supply Operation
• Low Skew 3ps Typical
• Fully Specified from –40°C to 125°C
• 12-Lead MSOP and 3mm × 3mm DFN Packages

Typical Application

Description

The LTC®6957-1/LTC6957-2/LTC6957-3/LTC6957-4 is a family of very low phase noise, dual output AC signal buffer/driver/logic level translators. The input signal can be a sine wave or any logic level (≤2V_P-P). There are four members of the family that differ in their output logic signal type as follows:

LTC6957-1: LVPECL Logic Outputs

LTC6957-2: LVDS Logic Outputs

LTC6957-3: CMOS Logic, In-Phase Outputs

LTC6957-4: CMOS Logic, Complementary Outputs

The LTC6957 will buffer and distribute any logic signal with minimal additive noise, however, the part really excels at translating sine wave signals to logic levels. The early amplifier stages have selectable lowpass filtering to minimize the noise while still amplifying the signal to increase its slew rate. This input stage filtering/noise limiting is especially helpful in delivering the lowest possible phase noise signal with slow slewing input signals such as a typical 10MHz sine wave system reference.